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Secretor status controls mucosal histo-blood group antigen expression and is associated with susceptibility to rotavirus (RV) diarrhea, with nonsecretors less susceptible to symptomatic infection. The role of breast milk secretor status on oral live-attenuated RV vaccine response in breastfed infants has not been explored. In a monovalent G1P[8] RV vaccine (Rotarix) trial in Bangladesh, RV-specific plasma immunoglobulin A antibody seroconversion rates were higher among infants of maternal nonsecretors (39%) than infants of maternal secretors (23%; P = .001). Maternal status remained a significant predictor when correcting for infant status (P = .002). Maternal secretor status should be considered when interpreting oral RV vaccine responses in low- and middle-income settings. Clinical Trials Registration. NCT01375647. [ABSTRACT FROM AUTHOR]

Wen Li and Alan Engelman established the essential SIV SB rcm sb infectivity assays to validate the virus as a model for HIV-1 drug resistance studies, and Cherepanov refined the SIV SB rcm sb intasome structure at a near atomic resolution [[24]]. Graph Peter Cherepanov studied Chemistry and Natural Sciences at the Novosibirsk State University (USSR), which is located in Academic Town amidst dozens of research institutes. 10.1038/nm1329 8 Engelman A, Cherepanov P. The lentiviral integrase binding protein LEDGF/p75 and HIV-1 replication. Having defended his PhD thesis in 2000, Cherepanov spent over a year painstakingly characterizing biochemical properties of HIV-1 IN in human cell extracts, which led him to identify LEDGF/p75 as the major cellular IN-binding partner [[4]]. [Extracted from the article]

Feline leukemia virus (FeLV) is associated with a range of clinical signs in felid species. Differences in disease processes are closely related to genetic variation in the envelope (env) region of the genome of six defined subgroups. The primary hosts of FeLV are domestic cats of the Felis genus that also harbor endogenous FeLV (enFeLV) elements stably integrated in their genomes. EnFeLV elements display 86% nucleotide identity to exogenous, horizontally transmitted FeLV (FeLV-A). Variation between enFeLV and FeLV-A is primarily in the long terminal repeat (LTR) and env regions, which potentiates generation of the FeLV-B recombinant subgroup during natural infection. The aim of this study was to examine recombination behavior of exogenous FeLV (exFeLV) and enFeLV in a natural FeLV epizootic. We previously described that of 65 individuals in a closed colony, 32 had productive FeLV-A infection, and 22 of these individuals had detectable circulating FeLV-B. We cloned and sequenced the env gene of FeLV-B, FeLV-A, and enFeLV spanning known recombination breakpoints and examined between 1 and 13 clones in 22 animals with FeLV-B to assess sequence diversity and recombination breakpoints. Our analysis revealed that FeLV-A sequences circulating in the population, as well as enFeLV env sequences, are highly conserved. We documented many recombination breakpoints resulting in the production of unique FeLV-B genotypes. More than half of the cats harbored more than one FeLV-B variant, suggesting multiple recombination events between enFeLV and FeLV-A. We concluded that FeLV-B was predominantly generated de novo within each host, although we could not definitively rule out horizontal transmission, as nearly all cats harbored FeLV-B sequences that were genetically highly similar to those identified in other individuals. This work represents a comprehensive analysis of endogenous-exogenous retroviral interactions with important insights into host-virus interactions that underlie disease pathogenesis in a natural setting. IMPORTANCE Feline leukemia virus (FeLV) is a felid retrovirus with a variety of disease outcomes. Exogenous FeLV-A is the virus subgroup almost exclusively transmitted between cats. Recombination between FeLV-A and endogenous FeLV analogues in the cat genome may result in emergence of largely replication-defective but highly virulent subgroups. FeLV-B is formed when the 39 envelope (env) region of endogenous FeLV (enFeLV) recombines with that of the exogenous FeLV (exFeLV) during viral reverse transcription and integration. Both domestic cats and wild relatives of the Felis genus harbor enFeLV, which has been shown to limit FeLV-A disease outcome. However, enFeLV also contributes genetic material to the recombinant FeLV-B subgroup. This study evaluates endogenousexogenous recombination outcomes in a naturally infected closed colony of cats to determine mechanisms and risk of endogenous retroviral recombination during exogenous virus exposure that leads to enhanced virulence. While FeLV-A and enFeLV env regions were highly conserved from cat to cat, nearly all individuals with emergent FeLV-B had unique combinations of genotypes, representative of a wide range of recombination sites within env. The findings provide insight into unique recombination patterns for emergence of new pathogens and can be related to similar viruses across species. [ABSTRACT FROM AUTHOR]

Natural killer (NK) cells are important early responders against viral infections. Changes in metabolism are crucial to fuel NK cell responses, and altered metabolism is linked to NK cell dysfunction in obesity and cancer. However, very little is known about the metabolic requirements of NK cells during acute retroviral infection and their importance for antiviral immunity. Here, using the Friend retrovirus mouse model, we show that following infection NK cells increase nutrient uptake, including amino acids and iron, and reprogram their metabolic machinery by increasing glycolysis and mitochondrial metabolism. Specific deletion of the amino acid transporter Slc7a5 has only discrete effects on NK cells, but iron deficiency profoundly impaires NK cell antiviral functions, leading to increased viral loads. Our study thus shows the requirement of nutrients and metabolism for the antiviral activity of NK cells, and has important implications for viral infections associated with altered iron levels such as HIV and SARS-CoV-2. Metabolic alterations control the fate and function of immune cells in response to infections, but the function of NK cell metabolism in the context of acute viral infections is unclear. Here the authors show that acute NK cell responses to Friend retrovirus involve increased glycolysis and mitochondrial metabolism and require amino acid transport as well as iron sufficiency. [ABSTRACT FROM AUTHOR]

Background: To inform the introduction of pneumococcal conjugate vaccine (PCV) and rotavirus vaccine, the World Health Organization (WHO) established the Global Invasive Bacterial Vaccine-Preventable Disease Surveillance Network (GISN) and the Global Rotavirus Surveillance Network (GRSN) in 2008. We investigated whether participation in these networks or other surveillance was associated with vaccine introduction.Methods: Between 2006 and 2018, among all WHO member states, we used multivariable models adjusting for economic status to assess (1) the association between surveillance for pneumococcal disease or rotavirus disease, including participation in GISN or GRSN and the introduction of the PCV or the rotavirus vaccine, respectively, and (2) the association between the rotavirus disease burden and the rotavirus vaccine introduction among 56 countries participating in GRSN from 2008 to 2018.Results: Countries that participated in or conducted surveillance for invasive pneumococcal disease or rotavirus disease were 3.5 (95% confidence interval [CI], 1.7-7.1) and 4.2 (95% CI, 2.1-8.6) times more likely to introduce PCV or rotavirus respectively, compared to those without surveillance. Among countries participating in GRSN, there was insufficient evidence to demonstrate an association between countries with higher rotavirus positivity and vaccine introduction.Conclusions: Surveillance should be incorporated into advocacy strategies to encourage the introduction of vaccines, with countries benefiting from data from, support for, and coordination of international disease surveillance networks. [ABSTRACT FROM AUTHOR]

The utility of neutrophil-lymphocyte ratio (NLR), monocyte-lymphocyte ratio (MLR), and platelet-lymphocyte ratio (PLR) as prognostic markers in Feline Leukemia Virus (FeLV) and Feline Immunodeficiency Virus (FIV) infections has not yet been investigated. The aim of this study was to investigate these leukocyte ratios in retrovirus-positive cats and to evaluate their prognostic value for survival. This retrospective case-control study included 142 cats, 75 FIV-Antibodies (Ab)-positive, 52 FeLV-Antigen (Ag)-positive, and 15 FIV-Ab+FeLV-Ag-positive, and a control population of 142 retrovirus-negative age-, sex-, and lifestyle-matched cats. Signalment, complete blood count at the time of serological testing, and outcome were recorded. Leukocyte ratios were compared within the same case-control population, among the three retrovirus-seropositive populations, and were related to survival time. No significant difference was found in NLR, MLR, or PLR between FIV-Ab-positive and FIV-Ab+FeLV-Ag-positive cats and their cross-matched controls. In the FeLV-Ag-positive population, MLR was significantly lower than in the control population (0.05 and 0.14, respectively, P =0.0008). No ratio discriminated among the three infectious states. No ratio was significantly different between survivors and non-survivors in the population of FIV-Ab-positive cats. MLR at diagnosis was significantly higher in FeLV-Ag-positive cats that died 1–3 years after diagnosis than in FeLV-Ag-positive cats still alive at 3 years (P =0.0284). None of the three ratios could predict retroviruses-positive cats that would survive to the end of the study. Overall the results indicate that NLR, MLR, and PLR are not significantly different among retrovirus statuses evaluated and had a very limited prognostic value for the survival time in retrovirus-positive cats. • The utility of leukocyte ratios as prognostic markers in FeLV and FIV infections has not yet been investigated. • Monocyte-lymphocyte ratio (MLR) was significantly lower in FeLV-Ag-positive cats than in the negative cross-matched cats. • None of the leukocyte ratios could predict retroviruses-seropositive cats that would survive to the end of the study. • MLR at diagnosis was significantly higher in FeLV-Ag-positive cats that died 1-3 years after diagnosis. [ABSTRACT FROM AUTHOR]

Dendritic cells (DC) subsets, like Langerhans cells (LC), are immune cells involved in pathogen sensing. They express specific antimicrobial cellular factors that are able to restrict infection and limit further pathogen transmission. Here, we identify the alarmin S100A9 as a novel intracellular antiretroviral factor expressed in human monocyte‐derived and skin‐derived LC. The intracellular expression of S100A9 is decreased upon LC maturation and inversely correlates with enhanced susceptibility to HIV‐1 infection of LC. Furthermore, silencing of S100A9 in primary human LC relieves HIV‐1 restriction while ectopic expression of S100A9 in various cell lines promotes intrinsic resistance to both HIV‐1 and MLV infection by acting on reverse transcription. Mechanistically, the intracellular expression of S100A9 alters viral capsid uncoating and reverse transcription. S100A9 also shows potent inhibitory effect against HIV‐1 and MMLV reverse transcriptase (RTase) activity in vitro in a divalent cation‐dependent manner. Our findings uncover an unexpected intracellular function of the human alarmin S100A9 in regulating antiretroviral immunity in Langerhans cells. Synopsis: Human Langerhans cells (LC) are known to be refractory to HIV‐1 infection, however precise mechanisms remain unknown. Here we show that human S100A9 inhibits HIV‐1 infection of human LC at the reverse transcription step of the viral replication cycle. The activity of the HIV‐1 reverse transcriptase is decreased in vitro and ex vivo in presence of S100A9 in a Mg2+‐dependent manner suggestive of a mechanism involving S100A9‐mediated chelation of divalent cations. TGF‐β modulates the expression and subcellular localization of S100A9 in myeloid‐derived cells.Endogenous S100A9 expression in human Langerhans cells limits HIV‐1 infection.S100A9 ectopic expression restricts infection by HIV‐1 and other retroviruses.The presence of S100A9 inhibits reverse transcriptase activity ex vivo and in vitro.The S100A9‐mediated antiviral activity is regulated in a Mg2+‐dependent manner. [ABSTRACT FROM AUTHOR]

Background Despite the demonstrated impact of pneumococcal vaccine (PCV) implementation on otitis media (OM), demonstration of real-life serotype-specific effectiveness of the 7-valent and 13-valent PCVs (PCV7 and PCV13) is lacking owing to the paucity of culture-positive cases. Furthermore, prelicensure PCV13 efficacy against OM was not studied. Methods The study was conducted from October 2009 to July 2013. Case patients were children aged 5–35 months with OM (mostly complex OM [recurrent/nonresponsive, spontaneously draining, chronic with effusion]) from whom middle-ear fluid culture was obtained; controls were contemporary children with rotavirus-negative gastroenteritis in a prospective population-based rotavirus surveillance, from the same age group with similar ethnic distribution and geographic location. Vaccine effectiveness (VE) was estimated as 1 minus the odds ratio using unconditional logistic regression, adjusting for time since PCV implementation, age, and ethnicity. Results A total of 223 case patients and 1370 controls were studied. Serotypes 19F and 19A together caused 56.1% of all vaccine-type (VT) OM. VE of ≥2 PCV doses in children aged 5–35 months was demonstrated as follows: PCV7 against OM due to PCV7 serotypes, 57.2% (95% confidence interval, 6.0%–80.5%); PCV13 against OM due to PCV13 serotypes, 77.4% (53.3%–92.1%); PCV13 against OM due to the 6 additional non-PCV7 serotypes 67.4% (17.6%–87.1%); PCV13 against OM due to serotype 19F, 91.3% (1.4%–99.2%); and PCV13 against OM due to serotype 3, 85.2% (23.9%–98.4%). PCV7 and PCV13 VE against OM due to serotype 19A in children aged 12–35 months was 72.4% (95% confidence interval, 6.2%–91.9%) and 94.6% (33.9%–99.6%), respectively. Conclusions PCV7 and PCV13 were effective against complex OM caused by the targeted serotypes. [ABSTRACT FROM AUTHOR]

Human gammaherpesviruses Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV) persist as life-long infections alternating between latency and lytic replication. Human endogenous retroviruses (HERVs), via integration into the host genome, represent genetic remnants of ancient retroviral infections. Both show similar epigenetic silencing while dormant, but can reactivate in response to cell signaling cues or triggers that, for gammaherpesviruses, result in productive lytic replication. Given their co-existence with humans and shared epigenetic silencing, we asked if HERV expression might be linked to lytic activation of human gammaherpesviruses. We found ERVW-1 mRNA, encoding the functional HERV-W envelope protein Syncytin-1, along with other repeat class elements, to be elevated upon lytic activation of EBV. Knockdown/knockout of ERVW-1 reduced lytic activation of EBV and KSHV in response to various lytic cycle triggers. In this regard, reduced expression of immediate early proteins ZEBRA and RTA for EBV and KSHV, respectively, places Syncytin-1's influence on lytic activation mechanistically upstream of the latent-to-lytic switch. Conversely, overexpression of Syncytin-1 enhanced lytic activation of EBV and KSHV in response to lytic triggers, though this was not sufficient to induce lytic activation in the absence of such triggers. Syncytin-1 is expressed in replicating B cell blasts and lymphoma-derived B cell lines where it appears to contribute to cell cycle progression. Together, human gammaherpesviruses and B cells appear to have adapted a dependency on Syncytin-1 that facilitates the ability of EBV and KSHV to activate lytic replication from latency, while promoting viral persistence during latency by contributing to B cell proliferation. [ABSTRACT FROM AUTHOR]

During retrovirus infection, a histone-free DNA copy of the viral RNA genome is synthesized and rapidly loaded with nucleosomes de novo upon nuclear entry. The potential role of viral accessory proteins in histone loading onto retroviral DNAs has not been extensively investigated. The p12 protein of Moloney murine leukemia virus (MMLV) is a virion protein that is critical for tethering the incoming viral DNA to host chromatin in the early stages of infection. Infection by virions containing a mutant p12 (PM14) defective in chromatin tethering results in the formation of viral DNAs that do not accumulate in the nucleus. In this report, we show that viral DNAs of these mutants are not loaded with histones. Moreover, the DNA genomes delivered by mutant p12 show prolonged association with viral structural proteins nucleocapsid (NC) and capsid (CA). The histone-poor viral DNA genomes do not become associated with the host RNA polymerase II machinery. These findings provide insights into fundamental aspects of retroviral biology, indicating that tethering to host chromatin by p12 and retention in the nucleus are required to allow loading of histones onto the viral DNA. [ABSTRACT FROM AUTHOR]

The rotavirus vaccine is a live vaccine, and there is a possibility of infection by the virus strain used in the vaccine. We investigated the process of determining whether an infection was caused by the vaccine strain in a severe complex immunodeficiency (SCID) patient with rotavirus infection. The patient was vaccinated with RotaTeq prior to being diagnosed with SCID. The testing process was conducted in the following order: confirming rotavirus infection, determining its genotype, and confirming the vaccine strain. Rotavirus infection was confirmed through enzyme immunoassay and VP6 gene detection. G1 and P[8] were identified by multiplex polymerase chain reaction for the genotype, and G3 was further identified using a single primer. By detecting the fingerprint gene (WC3) of RotaTeq, it was confirmed that the detected virus was the vaccine strain. Genotypes G1 and P[8] were identified, and the infection was suspected of having been caused by rotavirus G1P[8]. G1P[8] is the most commonly detected genotype worldwide and is not included in the recombinant strains used in vaccines. Therefore, the infection was confirmed to have been caused by the vaccine strain by analyzing the genetic relationship between VP4 and VP7. Rotavirus infection by the vaccine strain can be identified through genotyping and fingerprint gene detection. However, genetic linkage analysis will also help to identify vaccine strains. [ABSTRACT FROM AUTHOR]

Early events in retrovirus transmission are determined by interactions between incoming viruses and frontline cells near entry sites. Despite their importance for retroviral pathogenesis, very little is known about these events. We developed a bioluminescence imaging (BLI)-guided multiscale imaging approach to study these events in vivo. Engineered murine leukemia reporter viruses allowed us to monitor individual stages of retrovirus life cycle including virus particle flow, virus entry into cells, infection and spread for retroorbital, subcutaneous, and oral routes. BLI permitted temporal tracking of orally administered retroviruses along the gastrointestinal tract as they traversed the lumen through Peyer's patches to reach the draining mesenteric sac. Importantly, capture and acquisition of lymph-, blood-, and milk-borne retroviruses spanning three routes was promoted by a common host factor, the I-type lectin CD169, expressed on sentinel macrophages. These results highlight how retroviruses co-opt the immune surveillance function of tissue-resident sentinel macrophages for establishing infection. [ABSTRACT FROM AUTHOR]

Background: Retroviruses exist as exogenous infectious agents and as endogenous retroviruses (ERVs) integrated into host chromosomes. Such endogenous retroviruses (ERVs) are grouped into three classes roughly corresponding to the seven genera of infectious retroviruses: class I (gamma-, epsilonretroviruses), class II (alpha-, beta-, delta-, lentiretroviruses) and class III (spumaretroviruses). Some ERVs have counterparts among the known infectious retroviruses, while others represent paleovirological relics of extinct or undiscovered retroviruses. Results: Here we identify an intact ERV in the Anuran amphibian, Xenopus tropicalis. XtERV-S has open reading frames (ORFs) for gag, pol (polymerase) and env (envelope) genes, with a small additional ORF in pol and a serine tRNA primer binding site. It has unusual features and domain relationships to known retroviruses. Analyses based on phylogeny and functional motifs establish that XtERV-S gag and pol genes are related to the ancient env-less class III ERV-L family but the surface subunit of env is unrelated to known retroviruses while its transmembrane subunit is class I-like. LTR constructs show transcriptional activity, and XtERV-S transcripts are detected in embryos after the maternal to zygotic mid-blastula transition and before the late tailbud stage. Tagged Gag protein shows typical subcellular localization. The presence of ORFs in all three protein-coding regions along with identical 5' and 3' LTRs (long terminal repeats) indicate this is a very recent germline acquisition. There are older, full-length, nonorthologous, defective copies in Xenopus laevis and the distantly related African bullfrog, Pyxicephalus adspersus. Additional older, internally deleted copies in X. tropicalis carry a 300 bp LTR substitution. Conclusions: XtERV-S represents a genera-spanning member of the largely env-less class III ERV that has ancient and modern copies in Anurans. This provirus has an env ORF with a surface subunit unrelated to known retroviruses and a transmembrane subunit related to class I gammaretroviruses in sequence and organization, and is expressed in early embryogenesis. Additional XtERV-S-related but defective copies are present in X. tropicalis and other African frog taxa. XtERV-S is an unusual class III ERV variant, and it may represent an important transitional retroviral form that has been spreading in African frogs for tens of millions of years. [ABSTRACT FROM AUTHOR]

Endogenous retroviruses (ERVs) are sequences in animal genomes that originated from ancient retrovirus infections; they provide genetic novelty in hosts by being coopted as functional genes or elements during evolution. Recently, we demonstrated that endogenous elements from not only from retroviruses but also nonretroviral RNA viruses are a possible source of functional genes in host animals. The remnants of ancient bornavirus infections, called endogenous bornavirus-like elements (EBLs), are present in the genomes of a wide variety of vertebrate species, and some express functional products in host cells. Previous studies have predicted that the human EBL locus derived from bornavirus nucleoprotein, termed hsEBLN-2, expresses mRNA encoding a protein, suggesting that hsEBLN-2 has acquired a cellular function during evolution. However, the detailed function of the hsEBLN-2-derived product remains to be elucidated. In this study, we show that the hsEBLN-2-derived protein E2 acts as a mitochondrial protein that interacts with mitochondrial host factors associated with apoptosis, such as HAX-1. We also demonstrate that knockdown of hsEBLN-2-derived RNA increased the levels of PARP and caspase-3 cleavage and markedly decreased cell viability. In contrast, overexpression of E2 enhanced cell viability, as well as the intracellular stability of HAX-1, under stress conditions. Our results suggest that hsEBLN-2 has been coopted as a host gene, the product of which is involved in cell viability by interacting with mitochondrial proteins. IMPORTANCE Our genomes contain molecular fossils of ancient viruses, called endogenous virus elements (EVEs). Mounting evidence suggests that EVEs derived from nonretroviral RNA viruses have acquired functions in host cells during evolution. Previous studies have revealed that a locus encoding a bornavirus-derived EVE, hsEBLN-2, which was generated approximately 43 million years ago in a human ancestor, may be linked to the development of some tumors. However, the function of hsEBLN-2 has not been determined. In this study, we found that the E2 protein, an expression product of hsEBLN-2, interacts with apoptosis-related host proteins as a mitochondrial protein and affects cell viability. This study suggests that nonretroviral RNA viral EVEs have been coopted by hosts with more diverse functions than previously thought, showing a pivotal role for RNA virus infection in evolution. [ABSTRACT FROM AUTHOR]

The ancestor of cetaceans underwent a macroevolutionary transition from land to water early in the Eocene Period >50 million years ago. However, little is known about how diverse retroviruses evolved during this shift from terrestrial to aquatic environments. Did retroviruses transition into water accompanying their hosts? Did retroviruses infect cetaceans through cross-species transmission after cetaceans invaded the aquatic environments? Endogenous retroviruses (ERVs) provide important molecular fossils for tracing the evolution of retroviruses during this macroevolutionary transition. Here, we use a phylogenomic approach to study the origin and evolution of ERVs in cetaceans. We identify a total of 8,724 ERVs within the genomes of 25 cetaceans, and phylogenetic analyses suggest these ERVs cluster into 315 independent lineages, each of which represents one or more independent endogenization events. We find that cetacean ERVs originated through two possible routes. 298 ERV lineages may derive from retrovirus endogenization that occurred before or during the transition from land to water of cetaceans, and most of these cetacean ERVs were reaching evolutionary dead-ends. 17 ERV lineages are likely to arise from independent retrovirus endogenization events that occurred after the split of mysticetes and odontocetes, indicating that diverse retroviruses infected cetaceans through cross-species transmission from non-cetacean mammals after the transition to aquatic life of cetaceans. Both integration time and synteny analyses support the recent or ongoing activity of multiple retroviral lineages in cetaceans, some of which proliferated into hundreds of copies within the host genomes. Although ERVs only recorded a proportion of past retroviral infections, our findings illuminate the complex evolution of retroviruses during one of the most marked macroevolutionary transitions in vertebrate history. Author summary: The ancestor of cetaceans invaded the aquatic environments >50 million years ago. Recent comparative genomic studies have begun to reveal the molecular mechanisms underlying the morphological and ecological transformation of cetaceans. However, it has been largely obscure how retroviruses evolved during this land-to-water transition. Endogenous retroviruses (ERVs) recorded past retroviral infections. Here, we systematically mined and analyzed ERVs in the genomes of 25 cetaceans, and found that cetacean ERVs clustered into 315 distinct lineages. Among these cetacean ERV lineages, 298 lineages may originate through retrovirus endogenization before or during the colonization of aquatic environments by cetaceans, and 17 lineages may arise from endogenization of retroviruses that infected cetaceans through cross-species transmission from non-cetacean mammals after the transition to aquatic life of cetaceans. Taken together, our study provides a unique snapshot of the evolution of retroviruses during a major macroevolutionary transition. [ABSTRACT FROM AUTHOR]

Background: Rotavirus vaccination is recommended in all countries to reduce the burden of diarrhea-related morbidity and mortality in children. In resource-limited settings, rotavirus vaccination in the national immunization program has important cost implications, and evidence for protection beyond the first year of life and against the evolving variety of rotavirus strains is important. We assessed the extended and strain-specific vaccine efficacy of a heat-stable, affordable oral rotavirus vaccine (Rotasiil, Serum Institute of India, Pune, India) against severe rotavirus gastroenteritis (SRVGE) among healthy infants in Niger.Methods and Findings: From August 2014 to November 2015, infants were randomized in a 1:1 ratio to receive 3 doses of Rotasiil or placebo at approximately 6, 10, and 14 weeks of age. Episodes of gastroenteritis were assessed through active and passive surveillance and graded using the Vesikari score. The primary endpoint was vaccine efficacy of 3 doses of vaccine versus placebo against a first episode of laboratory-confirmed SRVGE (Vesikari score ≥ 11) from 28 days after dose 3, as previously reported. At the time of the primary analysis, median age was 9.8 months. In the present paper, analyses of extended efficacy were undertaken for 3 periods (28 days after dose 3 to 1 year of age, 1 to 2 years of age, and the combined period 28 days after dose 3 to 2 years of age) and by individual rotavirus G type. Among the 3,508 infants included in the per-protocol efficacy analysis (mean age at first dose 6.5 weeks; 49% male), the vaccine provided significant protection against SRVGE through the first year of life (3.96 and 9.98 cases per 100 person-years for vaccine and placebo, respectively; vaccine efficacy 60.3%, 95% CI 43.6% to 72.1%) and over the entire efficacy follow-up period up to 2 years of age (2.13 and 4.69 cases per 100 person-years for vaccine and placebo, respectively; vaccine efficacy 54.7%, 95% CI 38.1% to 66.8%), but the difference was not statistically significant in the second year of life. Up to 2 years of age, rotavirus vaccination prevented 2.56 episodes of SRVGE per 100 child-years. Estimates of efficacy against SRVGE by individual rotavirus genotype were consistent with the overall protective efficacy. Study limitations include limited generalizability to settings with administration of oral polio virus due to low concomitant administration, limited power to assess vaccine efficacy in the second year of life owing to a low number of events among older children, potential bias due to censoring of placebo children at the time of study vaccine receipt, and suboptimal adapted severity scoring based on the Vesikari score, which was designed for use in settings with high parental literacy.Conclusions: Rotasiil provided protection against SRVGE in infants through an extended follow-up period of approximately 2 years. Protection was significant in the first year of life, when the disease burden and risk of death are highest, and against a changing pattern of rotavirus strains during the 2-year efficacy period. Rotavirus vaccines that are safe, effective, and protective against multiple strains represent the best hope for preventing the severe consequences of rotavirus infection, especially in resource-limited settings, where access to care may be limited. Studies such as this provide valuable information for the planning of national immunization programs and future vaccine development.Trial Registration: ClinicalTrials.gov NCT02145000. [ABSTRACT FROM AUTHOR]

Background: Despite extensive molecular epidemiological studies, the prevalence and characteristics of Mouse Mammary Tumor Virus-Like Virus (MMTV-LV) in Chinese women breast cancer are still unclear. Besides, the prevalence of MMTV-LV in women breast cancer tissue varies in different countries and its dependent factors remain inconclusive. Methods: In the first part of the study, a case-control study was performed. 119 breast cancer samples (84 from Northern China and 35 from Southern China) and 50 breast fibroadenoma specimens were collected from Chinese women patients. MMTV-like env sequence and the homology to MMTV env gene were analysed by semi-nested polymerase chain reaction (PCR). We also explored the association of MMTV-LV prevalence with sample sources (Southern and Northern China) and patients' clinicopathological characteristics. To investigate the dependent factors of the prevalence of MMTV-LV in breast cancer worldwide, a meta-analysis was conducted in the second part of the study. Results: We found that the prevalence of MMTV-LV was much higher in breast cancer tissues (17.65%) than that in breast fibroadenoma specimens (4.00%) (P < 0.05). MMTV-LV prevalence in Chinese women breast cancer tissues was significantly different between Southern China (5.71%) and Northern China (22.62%) (P < 0.05). The prevalence of MMTV-LV also associates significantly with expression of HER2, but shows no significant correlation with other parameters. In the meta-analysis, we found that MMTV-LV prevalence in breast cancer tissue was dependent on the distribution of M. domesticus mouse (M. d), M. musculus mouse (M.m) and M.castaneus mouse (M.c) worldwide (P < 0.05). Conclusion: The distribution of house mice may be a crucial environmental factor that explains the geographic differences in human breast cancer incidence. Our findings may provide a potential avenue of prevention, diagnosis and treatment for breast cancer. [ABSTRACT FROM AUTHOR]

Long disregarded as junk DNA or genomic dark matter, endogenous retroviruses (ERVs) have turned out to represent important components of the antiviral immune response. These remnants of once-infectious retroviruses not only regulate cellular immune activation, but may even directly target invading viral pathogens. In this Gem, we summarize mechanisms by which retroviral fossils protect us from viral infections. One focus will be on recent advances in the role of ERVs as regulators of antiviral gene expression. [ABSTRACT FROM AUTHOR]

Chemicals reactivating epigenetically silenced genes target diverse classes of enzymes, including DNMTs, HDACs, HMTs and BET protein family members. They can strongly influence the expression of genes and endogenous retroviral elements with concomitant dsRNA synthesis and massive transcription of LTRs. Chemicals reactivating gene expression may cause both beneficial effects in cancer cells and may be hazardous by promoting carcinogenesis. Among chemicals used in medicine and commerce, only a small fraction has been studied with respect to their influence on epigenetic silencing. Screening of chemicals reactivating silent genes requires adequate systems mimicking whole-genome processes. We used a HeLa TSA-inducible cell population (HeLa TI cells) obtained by retroviral infection of a GFP-containing vector followed by several rounds of cell sorting for screening purposes. Previously, the details of GFP epigenetic silencing in HeLa TI cells were thoroughly described. Herein, we show that the epigenetically repressed gene GFP is reactivated by 15 agents, including HDAC inhibitors–vorinostat, sodium butyrate, valproic acid, depsipeptide, pomiferin, and entinostat; DNMT inhibitors–decitabine, 5-azacytidine, RG108; HMT inhibitors–UNC0638, BIX01294, DZNep; a chromatin remodeler–curaxin CBL0137; and BET inhibitors–JQ-1 and JQ-35. We demonstrate that combinations of epigenetic modulators caused a significant increase in cell number with reactivated GFP compared to the individual effects of each agent. HeLa TI cells are competent to metabolize xenobiotics and possess constitutively expressed and inducible cytochrome P450 mono-oxygenases involved in xenobiotic biotransformation. Thus, HeLa TI cells may be used as an adequate test system for the extensive screening of chemicals, including those that must be metabolically activated. Studying the additional metabolic activation of xenobiotics, we surprisingly found that the rat liver S9 fraction, which has been widely used for xenobiotic activation in genotoxicity tests, reactivated epigenetically silenced genes. Applying the HeLa TI system, we show that N-nitrosodiphenylamine and N-nitrosodimethylamine reactivate epigenetically silenced genes, probably by affecting DNA methylation. [ABSTRACT FROM AUTHOR]

Haemotropic microorganisms are the most common bacteria that infect erythrocytes and are associated with anaemia of varying severity. The aim of this study was to focus on the occurrence of Mycoplasma haemofelis, Mycoplasma haemominutum, and Mycoplasma turicensis in cats. We followed infected individuals' breeding conditions, age, sex, basic haematological indices, and co-infection with one of the feline retroviruses. A total of 73 cats were investigated. Haemoplasmas were detected by PCR and verified by sequencing. Haematology examination was performed focusing on the number of erythrocytes, haemoglobin concentrations and haematocrit. A subset of 40 cat blood samples was examined by a rapid immunochromatography test to detect retroviruses. The following was found in our study group: M. haemofelis in 12.3% of individuals, M. haemominutum in 35.6% of individuals and M. turicensis in 17.8% of individuals. A highly significant difference was found between positive evidence of blood mycoplasmas in cats living only at home (15%) and in cats with access to the outside (69.8%). There was also a highly significant difference in the incidence of mycoplasma in cats over 3 years of age compared to 1-3 years of age and up to 1 year of age. There was no difference in the frequency of infections between the sexes. Blood mycoplasma infection in our group was not accompanied by fundamental changes in the haematological indices and was only reflected by a decrease in haemoglobin values in three cases. In a subset of cats that were also examined for the presence of retroviral infection, mycoplasma infection in blood was confirmed in all five positive cases. [ABSTRACT FROM AUTHOR]

Nonhomologous DNA end joining (NHEJ) is one of the major DNA double-strand break (DSB) repair pathways in eukaryotes. The well-known critical proteins involved in NHEJ include Ku70/80, DNA-PKcs, Artemis, DNA pol λ/μ, DNA ligase IV–XRCC4, and XLF. Recent studies have added a number of new proteins to the NHEJ repertoire namely paralog of XRCC4 and XLF (PAXX), modulator of retroviral infection (MRI)/ cell cycle regulator of NHEJ (CYREN), transactivation response DNA-binding protein (TARDBP) of 43 kDa (TDP-43), intermediate filament family orphan (IFFO1), ERCC excision repair 6 like 2 (ERCC6L2), and RNase H2. PAXX acts as a stabilizing factor for the main NHEJ components. MRI/CYREN seems to play a dual role stimulating NHEJ in the G1 phase of the cell cycle, while inhibiting the pathway in the S and G2 phases. TDP-43 can recruit the ligase IV–XRCC4 complex to the DSB sites and stimulate ligation in neuronal cells. RNase H2 excises out the ribonucleotides inserted during repair by DNA polymerase μ/TdT. This review provides a brief glimpse into how these new partners were discovered and their contribution to the mechanism and regulation of NHEJ. NHEJ is one of the major DNA DSB repair pathways in humans. During NHEJ, Ku heterodimer consisting of KU70/80 binds to DSBs, followed by end processing by nucleases, gap filling by error-prone DNA polymerases, and finally ligation of the nick performed by DNA ligase IV–XRCC4 complex. PAXX and MRI are two important recently identified proteins associated with NHEJ. Novel and important functions in NHEJ have been attributed to the already known proteins, TDP-43, FOXL2, and RNase H2. Discovery of new factors provide additional insights into the mechanism and regulation of NHEJ, and its potential use in targeted therapy in human pathologies. [ABSTRACT FROM AUTHOR]

Background Rotavirus is a common cause of severe pediatric acute gastroenteritis. Two vaccines are licensed in the United States and have demonstrated high effectiveness against moderate to severe disease. However, fewer data are available on rotavirus vaccine effectiveness (VE) against milder disease. Methods We leveraged active surveillance data from Kaiser Permanente Northwest to calculate rotavirus VE against medically attended rotavirus illness among age-eligible children. We utilized a test-negative case-control design and applied 4 distinct case definitions based on reverse transcription–quantitative real-time PCR (qRT-PCR) assay and enzyme immunoassay (EIA) test results. VE was calculated as 100 × (1 − odds ratio), and models were adjusted for age group. Results The VE analysis population comprised 842 children, 799 (95%) of whom had mild disease requiring at most a clinic visit and 698 (83%) of whom were fully vaccinated against rotavirus. Age-adjusted VE was 70% (95% confidence interval [CI], 37–86%) against disease defined solely by qRT-PCR results, 72% (95% CI, 31–89%) against disease as defined by qRT-PCR with a quantification cycle (C q ) value <27, 73% (95% CI, 32–90%) against disease that was qRT-PCR positive but EIA negative, and 62% (95% CI, –20–88%) against disease defined solely by EIA. Results were similar when restricting to disease resulting in at most an ambulatory clinic or emergency department visit. Conclusions These results support the effectiveness of rotavirus vaccination in protecting US children from mild to moderate and severe disease. Our findings are also useful to show the effectiveness of rotavirus vaccination against qRT-PCR–defined illness. [ABSTRACT FROM AUTHOR]

APOBEC3 (A3) proteins are a family of host antiviral restriction factors that potently inhibit various retroviral infections, including human immunodeficiency virus (HIV)‐1. To overcome this restriction, HIV‐1 virion infectivity factor (Vif) recruits the cellular cofactor CBFβ to assist in targeting A3 proteins to a host E3 ligase complex for polyubiquitination and subsequent proteasomal degradation. Intervention of the Vif‐A3 interactions could be a promising therapeutic strategy to facilitate A3‐mediated suppression of HIV‐1 in patients. In this structural snapshot, we review the structural features of the recently determined structure of human A3F in complex with HIV‐1 Vif and its cofactor CBFβ, discuss insights into the molecular principles of Vif‐A3 interplay during the arms race between the virus and host, and highlight the therapeutic implications. [ABSTRACT FROM AUTHOR]

BACKGROUND: Private wells are an important source of drinking water in Kewaunee County, Wisconsin. Due to the region's fractured dolomite aquifer, these wells are vulnerable to contamination by human and zoonotic gastrointestinal pathogens originating from land-applied cattle manure and private septic systems. OBJECTIVE: We determined the magnitude of the health burden associated with contamination of private wells in Kewaunee County by feces-borne gastrointestinal pathogens. METHODS: This study used data from a year-long countywide pathogen occurrence study as inputs into a quantitative microbial risk assessment (QMRA) to predict the total cases of acute gastrointestinal illness (AGI) caused by private well contamination in the county. Microbial source tracking was used to associate predicted cases of illness with bovine, human, or unknown fecal sources. RESULTS: Results suggest that private well contamination could be responsible for as many as 301 AGI cases per year in Kewaunee County, and that 230 and 12 cases per year were associated with a bovine and human fecal source, respectively. Furthermore, Cryptosporidium parvum was predicted to cause 190 cases per year, the most out of all 8 pathogens included in the QMRA. DISCUSSION: This study has important implications for land use and water resource management in Kewaunee County and informs the public health impacts of consuming drinking water produced in other similarly vulnerable hydrogeological settings. [ABSTRACT FROM AUTHOR]

Nonpathogenic retroviruses of the Spumaretrovirinae subfamily can persist long term in the cytoplasm of infected cells, completing their life cycle only after the nuclear membrane dissolves at the time of cell division. Since the targeting of slowly dividing cancer cells remains an unmet need in oncolytic virotherapy, we constructed a replication-competent foamy virus vector (oFV) from the genomes of two chimpanzee simian foamy viruses (PAN1 and PAN2) and inserted a green fluorescent protein (GFP) transgene in place of the bel-2 open reading frame. oFV-GFP infected and propagated with slow kinetics in multiple human tumor cell lines, inducing a syncytial cytopathic effect. Infection of growth-arrested MRC5 cells was not productive, but oFV genomes persisted in the cytoplasm, and the productive viral life cycle resumed when cell division was later restored. In vivo, the virus propagated extensively in intraperitoneal ovarian cancer xenografts, slowing tumor growth, significantly prolonging survival of the treated mice, and sustaining GFP transgene expression for at least 45 days. Our data indicate that oFV is a promising new replication-competent viral and gene delivery platform for efficient targeting of the most fundamental trait of cancer cells, their ability to sustain chronic proliferation. [ABSTRACT FROM AUTHOR]

Background: Herbal remedies of Echinacea purpurea tinctures are widely used today to reduce common cold respiratory tract infections. Methods: Transcriptome, epigenome and kinome profiling allowed a systems biology level characterisation of genomewide immunomodulatory effects of a standardized Echinacea purpurea (L.) Moench extract in THP1 monocytes. Results: Gene expression and DNA methylation analysis revealed that Echinaforce® treatment triggers antiviral innate immunity pathways, involving tonic IFN signaling, activation of pattern recognition receptors, chemotaxis and immunometabolism. Furthermore, phosphopeptide based kinome activity profiling and pharmacological inhibitor experiments with filgotinib confirm a key role for Janus Kinase (JAK)-1 dependent gene expression changes in innate immune signaling. Finally, Echinaforce® treatment induces DNA hypermethylation at intergenic CpG, long/short interspersed nuclear DNA repeat elements (LINE, SINE) or long termininal DNA repeats (LTR). This changes transcription of flanking endogenous retroviral sequences (HERVs), involved in an evolutionary conserved (epi) genomic protective response against viral infections. Conclusions: Altogether, our results suggest that Echinaforce® phytochemicals strengthen antiviral innate immunity through tonic IFN regulation of pattern recognition and chemokine gene expression and DNA repeat hypermethylated silencing of HERVs in monocytes. These results suggest that immunomodulation by Echinaforce® treatment holds promise to reduce symptoms and duration of infection episodes of common cold corona viruses (CoV), Severe Acute Respiratory Syndrome (SARS)-CoV, and new occurring strains such as SARS-CoV-2, with strongly impaired interferon (IFN) response and weak innate antiviral defense. [ABSTRACT FROM AUTHOR]

Objective: Rotavirus A (RVA) is a significant cause of severe diarrheal illness and one of the common causes of death in children under the age of five. This study was aimed at detecting the prevalence of RVA in Pakistan after rotavirus vaccines were introduced. Fecal samples were obtained from 813 children from different hospitals in Rawalpindi and Islamabad, Pakistan, from January 2018 to December 2018. To obtain additional information from the parents / guardians of the children, a standard questionnaire was used.Results: Using an enzyme-linked immunosorbent assay kit (ELISA), rotavirus antigen was detected and ELISA positive samples were subjected to reverse transcription PCR (RT-PCR). The findings showed 22% prevalence of RVA in children with acute gastroenteritis (AGE) via ELISA and 21% prevalence via RT-PCR in children with AGE. There was no statistically significant difference between gender, age and RVA infections. The winter, spring and fall/autumn seasons were statistically significant for RVA prevalence.Conclusion: The present study will provide post vaccine prevalence data for the health policy makers. The implementation of rotavirus vaccines, along with adequate nutrition for babies, clean water supply and maternal hygienic activities during infant feeding, is recommended. Furthermore, continuous surveillance is mandatory in the whole country to calculate the disease burden caused by RVA. [ABSTRACT FROM AUTHOR]

Background: Rotavirus vaccine effectiveness is reduced among children in low-income countries. Indirect (transmission-mediated) effects of rotavirus vaccine might contribute to the total population effect of vaccination. We aimed to examine risk factors for transmission of rotavirus to household contacts in Blantyre, Malawi, and estimated the effectiveness of rotavirus vaccine in preventing transmission of infection to household contacts.Methods: In this prospective household cohort study, we recruited children born after Sept 17, 2012, and aged at least 6 weeks (vaccine-eligible children) with acute rotavirus gastroenteritis and their household contacts, in four government health facilities in Blantyre, Malawi. Clinical data, a bulk stool sample, and 1-2 mL of serum were collected from case children at presentation. Clinical data and stool samples were also prospectively collected from household contacts over 14 days from presentation. A single stool sample was collected from control households containing asymptomatic children who were frequency age-matched to case children. Samples were tested for rotavirus using semi-quantitative real-time PCR and for anti-rotavirus IgA using a semi-quantitative sandwich ELISA. Risk factors for household transmission of rotavirus infection and clinical disease, including disease severity and faecal shedding density, were identified using mixed effects logistic regression. Vaccine effectiveness against transmission was estimated as 1 minus the ratio of secondary attack rates in vaccinated and counterfactual unvaccinated populations, using vaccine effectiveness estimates from the associated diarrhoeal surveillance platform to estimate the counterfactual secondary attack rate without vaccination.Findings: Between Feb 16, 2015, and Nov 11, 2016, we recruited 196 case households (705 members) and 55 control households (153 members). Household secondary attack rate for rotavirus infection was high (434 [65%] of 665 individuals) and secondary attack rate for clinical disease was much lower (37 [5%] of 698). Asymptomatic infection in control households was common (40 [28%] of 144). Increasing disease severity in an index child (as measured by Vesikari score) was associated with increased risk of transmission of infection (odds ratio 1·17 [95% CI 1·06-1·30) and disease (1·28 [1·08-1·52]) to household contacts. Estimated vaccine effectiveness against transmission was 39% (95% CI 16-57).Interpretation: Rotavirus vaccine has the potential to substantially reduce household rotavirus transmission. This finding should be considered in clinical and health economic assessments of vaccine effectiveness.Funding: Wellcome Trust, US National Institutes of Health, and US National Institute of Allergy and Infectious Diseases. [ABSTRACT FROM AUTHOR]

Human endogenous retroviruses (HERVs) are remnants of ancient retroviral germline infections. Most HERV sequences are silenced in somatic cells, but interest is emerging on the involvement of HERV derived transcripts and proteins in human physiology and disease. A HERV‐W encoded protein, syncytin‐1, has been co‐opted into fetal physiology, where it plays a role in trophoblast formation. Altered HERV transcription and expression of HERV derived proteins are associated with various cancer types and neurological diseases such as multiple sclerosis (MS). The implication of HERVs as potential mediators of both health and disease suggests important roles of regulatory mechanisms and alterations of these in physiological and pathological processes. The regulation of HERV sequences is mediated by a wide variety of mechanisms, and the focus of this review is on selected aspects of these, including epigenetic mechanisms such as CpG methylation and histone modifications of the HP1‐H3K9me axis, viral transactivation events, and regulatory perspectives of transient stimuli in the microenvironment. Increasing knowledge of the regulation of HERV sequences will not only contribute to the understanding of complex pathogeneses, but also may pinpoint potential targets for better diagnosis and treatment in complex diseases as MS. [ABSTRACT FROM AUTHOR]

Retroviral insertional mutagenesis (RIM) is both a relevant risk in gene therapy and a powerful tool for identifying genes that enhance the competitiveness of repopulating hematopoietic stem and progenitor cells (HSPCs). However, focusing only on the gene closest to the retroviral vector insertion site (RVIS) may underestimate the effects of RIM, as dysregulation of distal and/or multiple genes by a single insertion event was reported in several studies. As a proof of concept, we examined the common insertion site (CIS) Bcl-xL, which revealed seven genes located within ±150 kb from the RVIS for our study. We confirmed that Bcl-xL enhanced the competitiveness of HSPCs, whereas the Bcl-xL neighbor Id1 hindered HSPC long-term repopulation. This negative influence of Id1 could be counteracted by co-expressing Bcl-xL. Interestingly, >90% of early reconstituted myeloid cells were found to originate from transduced HSPCs upon simultaneous overexpression of Bcl-xL and Id1, which implies that Bcl-xL and Id1 can collaborate to rapidly replenish the myeloid compartment under stress conditions. To directly compare the competitiveness of HSPCs conveyed by multiple transgenes, we developed a multiple competitor competitive repopulation (MCCR) assay to simultaneously screen effects on HSPC repopulating capacity in a single mouse. The MCCR assay revealed that multiple genes within a CIS can have positive or negative impact on hematopoiesis. Furthermore, these data highlight the importance of studying multiple genes located within the proximity of an insertion site to understand complex biological effects, especially as the number of gene therapy patients increases. [ABSTRACT FROM AUTHOR]

Rationale/Study design: A major challenge in the development of HIV vaccines is finding immunogens that elicit protection against a broad range of viral strains. Immunity to a narrow range of viral strains may protect infants of HIV-infected women or partners discordant for HIV. We hypothesized that immunization to the relevant viral variants could be achieved by exposure to infectious virus during prophylaxis with antiretroviral drugs. To explore this approach in an animal model, macaques were exposed to live virus (SIVmne or HIV-2287) during prophylaxis with parenteral tenofovir and humoral and cellular immune responses were quantified. Subsequently, experimental animals were challenged with homologous virus to evaluate protection from infection, and if infection occurred, the course of disease was compared to control animals. Experimental animals uninfected with SIVmne were challenged with heterologous HIV-2287 to assess resistance to retroviral infection. Methodology/Principal findings: Juvenile female Macaca nemestrina (N = 8) were given ten weekly intravaginal exposures with either moderately (SIVmne) or highly (HIV-2287) pathogenic virus during tenofovir prophylaxis. Tenofovir protected all 8 experimental animals from infection, while all untreated control animals became infected. Specific non-neutralizing antibodies were elicited in blood and vaginal secretions of experimental animals, but no ELISPOT responses were detected. Six weeks following the cessation of tenofovir, intravaginal challenge with homologous virus infected 2/4 (50%) of the SIVmne-immunized animals and 4/4 (100%) of the HIV-2287-immunized animals. The two SIVmne-infected and 3 (75%) HIV-2287-infected had attenuated disease, suggesting partial protection. Conclusions/Significance: Repeated exposure to SIVmne or HIV-2287, during antiretroviral prophylaxis that blocked infection, induced binding antibodies in the blood and mucosa, but not neutralizing antibodies or specific cellular immune responses. Studies to determine whether antibodies are similarly induced in breastfeeding infants and sexual partners discordant for HIV infection and receiving pre-exposure antiretroviral prophylaxis are warranted, including whether these antibodies appear to confer partial or complete protection from infection. [ABSTRACT FROM AUTHOR]

Detection, quantification and monitoring of virus – host cell interactions are of great importance when evaluating the safety of pharmaceutical products. With the wide usage of viral based vector systems in combination with mammalian cell lines for the production of biopharmaceuticals, the presence of replication competent viral particles needs to be avoided and potential hazards carefully assessed. Consequently, regulatory agencies recommend viral clearance studies using plaque assays or TCID50 assays to evaluate the efficiency of the production process in removing viruses. While plaque assays provide reliable information on the presence of viral contaminations, they are still tedious to perform and can take up to two weeks to finish. To overcome some of these limitations, we have automated, miniaturized and integrated the dual cell culture bioassay into a common lab-on-a-chip platform containing embedded electrical sensor arrays to enrich and detect infectious viruses. Results of our microfluidic single step assay show that a significant reduction in assay time down to 3 to 4 days can be achieved using simultaneous cell-based viral amplification, release and detection of cytopathic effects in a target cell line. We further demonstrate the enhancing effect of continuous fluid flow on infection of PG-4 reporter cells by newly formed and highly active virions by M. dunni cells, thus pointing to the importance of physical relevant viral–cell interactions. [ABSTRACT FROM AUTHOR]

Background: Diarrhoea remains among the highest causes of death in children under 5 years of age in developing countries. Before the introduction of rotavirus vaccine in Tanzania, rotavirus infection was the leading cause of severe diarrhoea in children below the age of 5 years but there is a paucity of studies reporting the severity of this infection after the introduction of rotavirus vaccine. This hospital-based study reports the proportion of children with rotavirus-associated diarrhoea in Dar es Salaam, its severity and associated factors.Methods: A hospital-based cross-sectional study was conducted at the inpatient and outpatient paediatrics departments of the selected health facilities from September 2018 to February 2019. A total of 314 children meeting inclusion criteria were enrolled into the study. A structured questionnaire was used to collect demographic and medical history, anthropometric measurements were taken and a stool sample was collected from each patient for rotavirus antigen detection using CTK Biotech Onsite rotavirus antigen rapid test.Results: A total of 314 children were included in the study with age range between 2 and 59 months. The median age was 12 months with an interquartile range of 8-19 months. Symptoms of rotavirus diarrhoea were vomiting (p-value = 0.018) and severe dehydration (p-value = 0.000). Independent associated factors of rotavirus diarrhoea included: age of mother between 35 and 49 years (AoR 4.1, 95% CI 1.0-17.1, p-value = 0.05), geographical distribution (Ilala District, AoR 4.0, 95% CI 1.1-10.4, p-value = 0.039), poor hand hygiene (AoR 8.5, 95% CI 2.6-28.1, p-value = 0.000) and drinking bottled/home-treated water (AoR 5.4, 95% CI 1.3-22.7, p-value = 0.02).Conclusion: Rotavirus infection is still prevalent and severe among children with diarrhoea. The difference in prevalence among the districts is also of concern and hence larger community-based cohort studies are needed to assess the association of rotavirus diarrhoea with the geographical variation across districts and regions. Improving sanitation and hygiene through health education amongst households is crucial for disease prevention. [ABSTRACT FROM AUTHOR]

Horizontal gene transfer from viruses to eukaryotic cells is a pervasive phenomenon. Somatic viral integrations are linked to persistent viral infection whereas integrations into germline cells are maintained in host genomes by vertical transmission and may be co‐opted for host functions. In the arboviral vector Aedes aegypti, an endogenous viral element from a nonretroviral RNA virus (nrEVE) was shown to produce PIWI‐interacting RNAs (piRNAs) to limit infection with a cognate virus. Thus, nrEVEs may constitute a heritable, sequence‐specific mechanism for antiviral immunity, analogous to piRNA‐mediated silencing of transposable elements. Here, we combine population genomics and evolutionary approaches to analyse the genomic architecture of nrEVEs in A. aegypti. We conducted a genome‐wide screen for adaptive nrEVEs and searched for novel population‐specific nrEVEs in the genomes of 80 individual wild‐caught mosquitoes from five geographical populations. We show a dynamic landscape of nrEVEs in mosquito genomes and identified five novel nrEVEs derived from two currently circulating viruses, providing evidence of the environmental‐dependent modification of a piRNA cluster. Overall, our results show that virus endogenization events are complex with only a few nrEVEs contributing to adaptive evolution in A. aegypti. [ABSTRACT FROM AUTHOR]

The first step of the intracellular phase of retroviral infection is the release of the viral capsid core in the cytoplasm. This structure contains the viral genetic material that will be reverse transcribed and integrated into the genome of infected cells. Up to recent times, the role of the capsid core was considered essentially to protect this genetic material during the earlier phases of this process. However, increasing evidence demonstrates that the permanence inside the cell of the capsid as an intact, or almost intact, structure is longer than thought. This suggests its involvement in more aspects of the infectious cycle than previously foreseen, particularly in the steps of viral genomic material translocation into the nucleus and in the phases preceding integration. During the trip across the infected cell, many host factors are brought to interact with the capsid, some possessing antiviral properties, others, serving as viral cofactors. All these interactions rely on the properties of the unique component of the capsid core, the capsid protein CA. Likely, the drawback of ensuring these multiple functions is the extreme genetic fragility that has been shown to characterize this protein. Here, we recapitulate the busy agenda of an HIV-1 capsid in the infectious process, in particular in the light of the most recent findings. [ABSTRACT FROM AUTHOR]

Background: Ethiopia launched free access for antiretroviral therapy in 2005. The number of patients on second line antiretroviral treatment has increased with each passing year. The objectives of this study were to describe the clinical, immunological and virologic outcomes of children and adolescents receiving second line anti-retroviral therapy in two referral hospitals, Yekatit 12 and Zewditu Memorial Hospitals, in Addis Ababa, Ethiopia. Methods: This was a hospital based retrospective cohort study conducted among children and adolescents aged 18 years and less and receiving a second line antiretroviral drugs. Data was collected using structured questionnaires. Means and percentages were used for nominal variables. Statistical analysis was made using statistical software–SPSS 23.0. Kaplan Meier analysis, long rank test and multivariate Cox proportion model were used to identify factors affecting survival. Results: A total of 75 children and adolescents were studied with a mean age of 13.28 years (SD: 4) with a mean treatment period on second line regimens of 35.2 months (SD: 21.8 months). Forty-eight participants were experiencing successful measures (in all three parameters) for their second line anti-retroviral treatment. Ten had virologic treatment failure while seven had died. Both treatment failure and death rates were higher within the first two years of treatment. Poor treatment adherence (Adjusted hazard ratio: 5.1 (95% CI: 1.1–23.2; p-value = 0.02)) and advanced World Health Organization clinical stage at start of the second line antiretrovirals (Adjusted hazard ratio: 7.51 (95% CI: 1.35–18.02; p-value = 0.002)) correlated significantly with survival of children and adolescents receiving treatment. Conclusions: The study describes clinical, immunological and virologic outcomes of second line antiretroviral treatment in a pediatric cohort under care in two hospitals in Addis Ababa, Ethiopia. Poor adherence and pre-treatment advanced clinical stages were predictors of survival. [ABSTRACT FROM AUTHOR]

Regulation of haematopoietic stem cell fate through conditional gene expression could improve understanding of healthy haematopoietic and leukaemia initiating cell (LIC) biology. We established conditionally immortalised myeloid progenitor cell lines co-expressing constitutive Hoxa9.EGFP and inducible Meis1.dTomato (H9M-ciMP) to study growth behaviour, immunophenotype and morphology under different cytokine/microenvironmental conditions ex vivo upon doxycycline (DOX) induction or removal. The vector design and drug-dependent selection approach identified new retroviral insertion (RVI) sites that potentially collaborate with Meis1/Hoxa9 and define H9M-ciMP fate. For most cell lines, myelomonocytic conditions supported reversible H9M-ciMP differentiation into neutrophils and macrophages with DOX-dependent modulation of Hoxa9/Meis1 and CD11b/Gr-1 expression. Here, up-regulation of Meis1/Hoxa9 promoted reconstitution of exponential expansion of immature H9M-ciMPs after DOX reapplication. Stem cell maintaining conditions supported selective H9M-ciMP exponential growth. H9M-ciMPs that had Ninj2 RVI and were cultured under myelomonocytic or stem cell maintaining conditions revealed the development of DOX-dependent acute myeloid leukaemia in a murine transplantation model. Transcriptional dysregulation of Ninj2 and distal genes surrounding RVI (Rad52, Kdm5a) was detected. All studied H9M-ciMPs demonstrated adaptation to T-lymphoid microenvironmental conditions while maintaining immature myelomonocytic features. Thus, the established system is relevant to leukaemia and stem cell biology. [ABSTRACT FROM AUTHOR]

Apolipoprotein B editing complex (APOBEC3/A3) genes are found in mammalian cells. In primates, there are 7 APOBEC3 genes, namely, 3A, 3B, 3C, 3DE, 3F, 3G, and 3H. Previous research has shown that A3 proteins help to inhibit viral infection via their cytidine deaminase activity. However, it has also been found that A3 proteins could lead to viral evolution, where retroviruses such as HIV (Human Immunodeficiency Virus), acquire beneficial mutations that enable them to overcome the antiviral activity of A3 proteins, gain resistance to certain drugs used for treating viral infections and escape recognition by the immune system. This paper is a review article summarizing the role of A3G on viral infection and evolution, and the potential impact viral evolution could have in treatment of retroviral infections such as HIV. [ABSTRACT FROM AUTHOR]

Repeated retroviral infections of vertebrate germlines have made endogenous retroviruses ubiquitous features of mammalian genomes. However, millions of years of evolution obscure many of the immediate repercussions of retroviral endogenisation on host health. Here we examine retroviral endogenisation during its earliest stages in the koala (Phascolarctos cinereus), a species undergoing germline invasion by koala retrovirus (KoRV) and affected by high cancer prevalence. We characterise KoRV integration sites (IS) in tumour and healthy tissues from 10 koalas, detecting 1002 unique IS, with hotspots of integration occurring in the vicinity of known cancer genes. We find that tumours accumulate novel IS, with proximate genes over-represented for cancer associations. We detect dysregulation of genes containing IS and identify a highly-expressed transduced oncogene. Our data provide insights into the tremendous mutational load suffered by the host during active retroviral germline invasion, a process repeatedly experienced and overcome during the evolution of vertebrate lineages. Koalas are susceptible to neoplasms, which are related to infection with the Koala retrovirus. Here, the authors use DNA sequencing to show that the retroviral insertion sites cluster near known cancer genes and demonstrate a high mutational load associated with the germline invasion of the virus. [ABSTRACT FROM AUTHOR]

Endogenous retroviruses (ERVs) are the remnants of past retroviral infections. Fossil records of class II retroviruses have been discovered in a range of vertebrates, with the exception of amphibians, which are known only to possess class I and class III-like ERVs. Through genomic mining of all available amphibian genomes, we identified, for the first time, class II ERVs in amphibians. The class II ERVs were found only in Gymnophiona (caecilians) and not in the genomes of the other amphibian orders, Anura (frogs and toads) and Caudata (salamanders and newts), which are phylogenetically closely related. Therefore, the ERV endogenization occurred after the split of Gymnophiona, Anura, and Caudata (323 million years ago). Investigation of phylogenetic relationship and genomic structure revealed that the ERVs may originate from alpha- or betaretroviruses. We offer evidence that class II ERVs infiltrated amphibian genomes recently and may still have infectious members. Remarkably, certain amphibian class II ERVs can be expressed in diverse tissues. This discovery closes the major gap in the retroviral fossil record of class II ERVs and provides important insights into the evolution of class II ERVs in vertebrates. IMPORTANCE Class II retroviruses, largely distributed among mammals and birds, are of particular importance for medicine and economics. Class II ERVs have been discovered in a range of vertebrates, with the exception of amphibians, which are known only to possess class I and class III-like ERVs. Here, for the first time, we discovered class II ERVs in amphibians. We also revealed that the ERVs may originate from alpha- or betaretroviruses. We revealed that class II ERVs were integrated into amphibian genomes recently and certain amphibian class II ERVs can be expressed in diverse tissues. Our discovery closes the major gap in the retroviral fossil record of class II ERVs, and also indicates that amphibians may be still infected by class II retroviruses. [ABSTRACT FROM AUTHOR]

The Democratic Republic of the Congo (DRC) has a history of nonhuman primate (NHP) consumption and exposure to simian retroviruses yet little is known about the extent of zoonotic simian retroviral infections in DRC. We examined the prevalence of human T-lymphotropic viruses (HTLV), a retrovirus group of simian origin, in a large population of persons with frequent NHP exposures and a history of simian foamy virus infection. We screened plasma from 3,051 persons living in rural villages in central DRC using HTLV EIA and western blot (WB). PCR amplification of HTLV tax and LTR sequences from buffy coat DNA was used to confirm infection and to measure proviral loads (pVLs). We used phylogenetic analyses of LTR sequences to infer evolutionary histories and potential transmission clusters. Questionnaire data was analyzed in conjunction with serological and molecular data. A relatively high proportion of the study population (5.4%, n = 165) were WB seropositive: 128 HTLV-1-like, 3 HTLV-2-like, and 34 HTLV-positive but untypeable profiles. 85 persons had HTLV indeterminate WB profiles. HTLV seroreactivity was higher in females, wives, heads of households, and increased with age. HTLV-1 LTR sequences from 109 persons clustered strongly with HTLV-1 and STLV-1 subtype B from humans and simians from DRC, with most sequences more closely related to STLV-1 from Allenopithecus nigroviridis (Allen's swamp monkey). While 18 potential transmission clusters were identified, most were in different households, villages, and health zones. Three HTLV-1-infected persons were co-infected with simian foamy virus. The mean and median percentage of HTLV-1 pVLs were 5.72% and 1.53%, respectively, but were not associated with age, NHP exposure, village, or gender. We document high HTLV prevalence in DRC likely originating from STLV-1. We demonstrate regional spread of HTLV-1 in DRC with pVLs reported to be associated with HTLV disease, supporting local and national public health measures to prevent spread and morbidity. Author summary: HTLV-1 is a human retrovirus of zoonotic simian origin that has spread globally causing inflammatory and carcinogenic disease. We previously showed that persons with high nonhuman primate (NHP) exposure in the Democratic Republic of the Congo (DRC) can be infected with another simian retrovirus, simian foamy virus (SFV), suggesting they are also at risk for infection with STLV-1. We conducted follow-up analysis of the same persons from rural villages of central DRC to determine exposure and transmission risks for STLV-1 and HTLV-1 infection. Most persons, especially women, reported high levels of NHP exposure. We identified possible introduction and spread of STLV-1 from a local monkey species across households, villages, and health zones in DRC. Most persons had HTLV-1 levels above those reported in previous studies for persons with disease. Our findings reveal that coordinated public health strategies are needed at both local and national levels to prevent further spread and morbidity of HTLV-1. [ABSTRACT FROM AUTHOR]

Background: G12 rotaviruses were first observed in sub-Saharan Africa in 2004 and since then have continued to emerge and spread across the continent and are reported as a significant human rotavirus genotype in several African countries, both prior to and after rotavirus vaccine introduction. This study investigated the genetic variability of 15 G12 rotavirus strains associated with either P[6] or P[8] identified between 2010 and 2014 from Ethiopia, Kenya, Rwanda, Tanzania, Togo and Zambia.Methods: The investigation was carried out by comparing partial VP7 and partial VP4 sequences of the African G12P[6] and G12P[8] strains with the available GenBank sequences and exploring the recognized neutralization epitopes of these strains. Additionally, Bayesian evolutionary analysis was carried out using Markov Chain Monte Carlo (MCMC) implemented in BEAST to estimate the time to the most recent ancestor and evolutionary rate for these G12 rotavirus strains.Results: The findings suggested that the VP7 and VP4 nucleotide and amino acid sequences of the G12 strains circulating in African countries are closely related, irrespective of country of origin and year of detection, with the exception of the Ethiopian strains that clustered distinctly. Neutralization epitope analysis revealed that rotavirus VP4 P[8] genes associated with G12 had amino acid sequences similar to those reported globally including the vaccine strains in RotaTeq and Rotarix. The estimated evolutionary rate of the G12 strains was 1.016 × 10- 3 substitutions/site/year and was comparable to what has been previously reported. Three sub-clusters formed within the current circulating lineage III shows the diversification of G12 from three independent ancestries within a similar time frame in the late 1990s.Conclusions: At present it appears to be unlikely that widespread vaccine use has driven the molecular evolution and sustainability of G12 strains in Africa. Continuous monitoring of rotavirus genotypes is recommended to assess the long-term impact of rotavirus vaccination on the dynamic nature of rotavirus evolution on the continent. [ABSTRACT FROM AUTHOR]

Eukaryotic cells produce extracellular vesicles (EVs) mediating intercellular communication. These vesicles encompass many bio-molecules such as proteins, nucleic acids, and lipids that are transported between cells and regulate pathophysiological actions in the recipient cell. Exosomes originate from multivesicular bodies inside cells and microvesicles shed from the plasma membrane and participate in various pathological conditions. Retroviruses such as Human Immunodeficiency Virus -type 1 (HIV-1) and Human T-cell leukemia virus (HTLV)-1 engage exosomes for spreading and infection. Exosomes from virus-infected cells transfer viral components such as miRNAs and proteins that promote infection and inflammation. Additionally, these exosomes deliver virus receptors to target cells that make them susceptible to virus entry. HIV-1 infected cells release exosomes that contribute to the pathogenesis including neurological disorders and malignancy. Exosomes can also potentially carry out as a modern approach for the development of HIV-1 and HTLV-1 vaccines. Furthermore, as exosomes are present in most biological fluids, they hold the supreme capacity for clinical usage in the early diagnosis and prognosis of viral infection and associated diseases. Our current knowledge of exosomes' role from virus-infected cells may provide an avenue for efficient retroviruses associated with disease prevention. However, the exact mechanism involved in retroviruses infection/ inflammation remains elusive and related exosomes research will shed light on the mechanisms of pathogenesis. [ABSTRACT FROM AUTHOR]

Background: Mozambique has a high burden of group A rotavirus (RVA) infection and chronic undernutrition. This study aimed to determine the frequency and potential risk factors for RVA infection in undernourished children under 5 years old with diarrhoea in Mozambique.Methods: The analysis was conducted using data from March 2015 to December 2017, regarding children under 5 years old with at least one type of undernutrition. Anthropometric measures were used to calculate indices of weight-for-age, weight-for-height and height-for-age through the Z-Scores. RVA results were extracted from the National Diarrhoea Surveillance database. Descriptive statistics, chi-square test was used for qualitative variables and organized in contingency tables and 95% Confidence Intervals (CI) were considered for the calculation of RVA infection proportion and in the multiple logistic regression models to estimate the adjusted odds ratios (AOR).Results: Of the 842 undernourished children included in the analysis, 27.2% (95% CI: 24.3-30.3%) were positive for RVA. The rate of RVA infection was 42.7% (95% CI: 38.0-47.5%) in the pre-vaccine period, with great reduction to 12.2% (95% CI: 9.4-15.6%) in the post-vaccine period. Most of the RVA undernourished children had severe wasting (33.3%) and severe stunting (32.0%). The risk of infection was significantly high in children from 0 to 11 months (p-value < 0.001) when compared to the age group of 24-59 months. A higher proportion of RVA infection was detected in households with five or more members (p-value = 0.029). Similar proportions of RVA were observed in children fed only by breast milk (34.9%) and breast milk with formula (35.6%). A higher proportion of undernourished HIV-positive children co-infected with RVA (7.4%) was observed.Conclusions: The frequency of RVA infection in undernourished children declined following the introduction of the vaccine in Mozambique. Beyond the temporal variation, Maputo province, age and crowded households were also associated to RVA infection. A high proportion of RVA infection was observed in children with severe wasting and a triple burden of disease: undernutrition, RVA and HIV, highlighting the need to conduct follow-up studies to understand the long-term impact of these conditions on children's development. [ABSTRACT FROM AUTHOR]

Background: Little is known about the etiology of childhood diarrhea in the United Arab Emirates (UAE) especially after the introduction of rotavirus vaccines. This study aimed to identify gastrointestinal pathogens in children with diarrhea (cases) and the carriage rate of these pathogens in asymptomatic children (controls).Methods: Stool samples were collected from 203 cases and 73 controls who presented to two major hospitals in Al Ain city, UAE. Samples were analyzed with Allplex™ Gastrointestinal Full Panel Assay for common entero-pathogens. The association between diarrhea and the isolated pathogens was calculated in a multivariate logistic regression model. The adjusted attributable fractions (aAFs) were calculated for all pathogens significantly associated with cases.Results: At least one pathogen was identified in 87 samples (42.8%) from cases and 17 (23.3%) from controls (P < 0.001). Rotavirus, norovirus GII and adenovirus were significantly more prevalent in cases. Their aAFs with 95% ci are 0.95 (0.64, 1.00) for rotavirus, 0.86 (0.38, 0.97) for norovirus GII and 0.84 (0.29, 0.96) for adenovirus. None of the 13 bacteria tested for were more commonly found in the cases than in controls. Cryptosporidium spp. were more significantly detected in cases than in controls. Co-infections occurred in 27.9% of the children. Viruses and parasites were significantly more likely to occur together only in the cases.Conclusions: Multiplex PCR revealed high positivity rates in both cases and controls which demand a cautious interpretation. Rotavirus remains the main childhood diarrhea pathogen in UAE. Effective strategies are needed to better control rotavirus and other causative pathogens. [ABSTRACT FROM AUTHOR]

Hematopoietic stem and progenitor cell (HSPC)-based ex vivo gene therapy has demonstrated clinical success for X-linked severe combined immunodeficiency (SCID-X1) patients who lack a suitable donor for HSPC transplantation. Nevertheless, this form of treatment is associated with an increased risk of infectious disease complications and genotoxicity mainly due to the conditioning regimen. In addition, ex vivo gene therapy approaches require sophisticated facilities to manufacture gene-modified cells and to care for the patients after chemotherapy. Considering these impediments, we have developed an in vivo gene therapy approach to treat canine SCID-X1 after HSPC mobilization and systemic delivery of the therapeutic vector. Here, we investigated the use of the cocal envelope to pseudotype a lentiviral (LV) vector expressing a functional gammaC gene. The cocal envelope is resistant to serum inactivation compared with the commonly used vesicular stomatitis virus envelope glycoprotein (VSV-G) envelope and thus well suited for systemic delivery. Two SCID-X1 neonatal canines treated with this approach achieved long-term therapeutic immune reconstitution with no prior conditioning. Therapeutic levels of gene-corrected CD3+ T cells were demonstrated for at least 16 months, and all other correlates of T cell functionality were within normal range. Retroviral integration-site analysis demonstrated polyclonal T cell reconstitution. Comparative analysis of integration profiles of foamy viral (FV) vector and cocal LV vector after in vivo gene therapy found distinct integration-site patterns. These data demonstrate that clinically relevant and durable correction of canine SCID-X1 can be achieved with in vivo delivery of cocal LV. Since manufacturing of cocal LV is similar to VSV-G LV, this approach is easily translatable to a clinical setting, thus providing for a highly portable and accessible gene therapy platform for SCID-X1. [ABSTRACT FROM AUTHOR]

Background: Understanding the interactions between the microRNA (miRNA) and mRNA of genes encoding restriction factors (RFs) can lead to the development of new antiretroviral strategies aimed at providing the resistance and reducing susceptibility of human cells to potential PERV infection. Among RFs TRIM family play an important role in shaping the immune response during various stages of infection. The aim of the study was to evaluate in vitro the transcriptional profile of TRIM family genes and identify complementary miRNAs in NHDF cells infected with PERVs and induced by gram negative lipopolysacharide (LPS). Methods: Human dermal fibroblasts cells were cultured in four separate conditions‐ 2 monocultures: control (N), treated with LPS (NL) and 2 co‐cultures with porcine PK15 cells: without LPS (NP) and treated with LPS (NLP). Bacterial LPS was used in this study as an inducer of inflammation in NHDF cells. After extraction of DNA and RNA from cells PERV infection was confirmed in co‐cultures by qPCR and RTqPCR. RNA extracts served as a matrix for HGU 133A 2.0 and miRNA 2.0 microarrays to evaluate the expression profile of the selected TRIM family genes and miRNAs adequately. TRIM 2, 14, 22, and 28 were selected for the validation of HGU 133A 2.0 results. Statistical analyses were performed with the use of REST© 2009 and Genespring GX 13.0. Transcriptome Analysis Console 4.0 program (Affymetrix) was used to identify miRNAs that differentiate the studied genes in all conditions. Results: Porcine endogenous retrovirus infection at DNA and RNA level was confirmed in NHDF cells in each of the tested groups (NP and NLP). Contamination was excluded in N and NL groups. Based on the analysis of HGU 133A 2.0 results 93 mRNA IDs of TRIM family genes differentiating analyzed conditions were selected P <.05. HGU 133A 2.0 mRNA fluorescence profile was confirmed with RTqPCR of TRIM2, TRIM14, TRIM22 and TRIM28 P <.05. TRIM14 down regulation was specific only in PERV monoinfection (group NP). In miRNA 2.0 microarray 346 miRNAs were identified as differentiating NHDF cells in all analyzed conditions, P <.05. According to the analysis with mirTAR platform and Microrna.org datatbase none of the selected miRNAs had the potential to regulate the selected genes of the TRIM family. Conclusion: Porcine endogenous retrovirus infection of NHDF cells is accompanied by TRIM14 down regulation suggesting TRIM14 as a possible marker of retroviral infection. None of the selected miRNAs had statistically significant potential to regulate the expression of the selected TRIMs in any of the analyzed conditions. [ABSTRACT FROM AUTHOR]

Background: Small ruminant lentivirus (SRLV) belong to genus Lentivirus, family Retroviridae. These viruses cause caprine arthritis encephalitis (CAE) and maedi visna (MV), infectious diseases that cause economic, production, and reproductive losses. There are no effective treatments or vaccines for these diseases. Thus, early detection via serology has great importance for control of SRLV. Therefore, the objective of this review is to demonstrate the potential of the western blot (WB) test as an immunodiagnostic test for SRLV. Review: In general, immunodiagnosis of SRLV is performed via agar gel immunodiffusion (AGID) and indirect enzymelinked immunosorbent assay (ELISA), which can detect antibodies in several different biological samples but is used preferably with serum and blood plasma. However, WB has demonstrated efficacy in the early diagnosis of immunoglobulins against SRLV, presenting higher sensitivity and specificity than the serological tests usually used, because this technique can detect antibodies at a dilution as much as 256 times greater than that of AGID and 32 times greater than that of ELISA. SRLV infection and consequent immunological activation result in the induction of cellular and humoral responses. Additionally, around the third week, production of antibodies directed mainly toward viral capsid proteins (p25 and p28) occurs. After the fifth week, production of immunoglobulins directed toward other viral proteins occurs. Because of the persistence of SRLV infection, serology is considered to be the most practical means to diagnosis. Each serological test has a percentage specificity and distinct sensitivity, as well as advantages and disadvantages in its applicability. It should be noted that there is no gold standard test for diagnosis of SRLV infection. Moreover, SRLV are characterized by escape mechanisms such as genetic diversity, mutagenic potential, viral intermittence, and the process of compartmentalization, which make immunodiagnosis more difficult. In addition, positive animals tend to present unstable levels of antibodies over weeks, months, and even years. In this context, WB, with early antibody detection, has been proven to be a refined and more accurate technique than other immunodiagnostic tests for SRLV. WB allows the simultaneous resolution of several immunogenic antigens present in a sample, and this feature provides it with greater reliability, differentiates it from other immunological methods, and accredits it as a test of wide applicability. Epidemiological and immunological dynamics studies often use WB in the immunodynamic diagnosis of SRLV. Serum, blood plasma, and seminal plasma are typical biological materials used in the serological diagnosis of SRLV with WB, expanding its potential as an immunodiagnosis method. Conclusion: WB is the most accurate serological technique for SRLV. It is more capable of accurate diagnosis because the genetic diversity that characterizes such lentiviruses and their various immune system escape mechanisms routinely hinder traditional diagnosis. Additionally, this test has been used widely in studies of SRLV for various purposes, but mainly in studies of epidemiological and immunological dynamics, using serum, blood plasma, or seminal plasma. However, independently of the biological sample tested, WB maintains high sensitivity and precision in immunodiagnosis, making it a refined and valid technique for SRLV control programs. [ABSTRACT FROM AUTHOR]

Objective: Acute gastroenteritis is an important cause for morbidity and mortality in the children. Rotavirus is an important viral agent in the etiology of childhood gastroenteritis globally. Rotavirus may vary depending on the climate and geographical territory. The aim of the present study was to search for the prevalence of rotavirus in pediatric patients who have referred due to acute gastroenteritis in Sanlıurfa province of South-Eastern Anatolia. Methods: Stool sample records of 5,777 cases who have referred to Harran University Hospital because of gastroenteritis between March 2016 and March 2018 were evaluated according to the age, season and month. Results: Rotavirus antigens were detected in 532 (9.2%) stool samples. The cases with positive viral antigen were most common in 13 to 24-month age group by 36.8%. The most common period was fall with a rate of 35.3%, and the most common month was October by 15.6%. Conclusions: Rotavirus gastroenteritis is observed with a prevalence rate of 9.2% in Sanliurfa province of South-eastern Anatolia. Rotavirus, the most common agent for gastroenteritis in pediatric patients below 2 years of age, between 13 and 24 months in particular, should be searched during October in fall season. [ABSTRACT FROM AUTHOR]