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Background: Gastric non-Helicobacter pylori helicobacters (NHPH) naturally colonize the stomach of animals. In humans, infection with these bacteria is associated with chronic active gastritis, peptic ulceration and MALT-lymphoma. H. bizzozeronii belongs to these NHPH and its prevalence in children is unknown., Case Presentation: This case report describes for the first time a NHPH infection in a 20-month-old girl with severe gastric disorders in Mexico. The patient suffered from melena, epigastric pain, and bloating. Gastroscopy showed presence of a Hiatus Hill grade I, a hemorrhagic gastropathy in the fundus and gastric body, and a Forrest class III ulcer in the fundus. Histopathologic examination revealed a chronic active gastritis with presence of long, spiral-shaped bacilli in the glandular lumen. Biopsies from antrum, body and incisure were negative for presence of H. pylori by culture and PCR, while all biopsies were positive for presence of H. bizzozeronii by PCR. Most likely, infection occurred through intense contact with the family dog. The patient received a triple therapy consisting of a proton pump inhibitor, clarithromycin, and amoxicillin for 14 days, completed with sucralfate for 6 weeks, resulting in the disappearance of her complaints., Conclusion: The eradication could not be confirmed, although it was suggested by clear improvement of symptoms. This case report further emphasizes the zoonotic importance of NHPH. It can be advised to routinely check for presence of both H. pylori and NHPH in human patients with gastric complains., (© 2023. The Author(s).)

Background: Gastric non-Helicobacter pylori Helicobacter (NHPH) species naturally associated with animals have been linked with gastric disease in human patients., Aim: The prevalence and clinical significance of zoonotic gastric NHPHs was determined in large and well-defined, H. pylori-negative, gastric patient populations., Methods: Patients were retrospectively (n = 464) and prospectively (n = 65) included for gastric biopsy collection: chronic gastritis (CG), peptic ulcer disease and gastric MALT lymphoma, without identified aetiology. PCR and sequencing was performed for the detection of gastric Helicobacter species. Retrospectively, asymptomatic gastric bypass patients (n = 38) were included as controls. Prospectively, additional saliva samples and symptom and risk factor questionnaires were collected. In this group, patients with gastric NHPH infection were administered standard H. pylori eradication therapy and underwent follow-up gastroscopy post-therapy., Results: In the retrospective samples, the prevalence of gastric NHPHs was 29.1%, while no gastric NHPHs were detected in control biopsies. In the prospective cohort, a similar proportion tested positive: 27.7% in gastric tissue and 20.6% in saliva. The sensitivity and accuracy for the detection of gastric NHPHs in saliva compared to gastric tissue was 27.8% and 69.8% respectively. Following eradication therapy, clinical remission was registered in 12 of 17 patients, histological remission in seven of nine and eradication in four of eight patients., Conclusion: These findings suggest a pathophysiological involvement of NHPHs in gastric disease. Patients presenting with gastric complaints may benefit from routine PCR testing for zoonotic gastric NHPHs., (© 2023 The Authors. Alimentary Pharmacology & Therapeutics published by John Wiley & Sons Ltd.)

The gut microbiota represents a diverse and dynamic population of microorganisms that can influence the health of the host. Increasing evidence supports the role of the gut microbiota as a key player in the pathogenesis of neurodegenerative diseases, including Alzheimer's disease (AD). Unfortunately, the mechanisms behind the interplay between gut pathogens and AD are still elusive. It is known that bacteria-derived outer membrane vesicles (OMVs) act as natural carriers of virulence factors that are central players in the pathogenesis of the bacteria. Helicobacter pylori (H. pylori) is a common gastric pathogen and H. pylori infection has been associated with an increased risk to develop AD. Here, we are the first to shed light on the role of OMVs derived from H. pylori on the brain in healthy conditions and on disease pathology in the case of AD. Our results reveal that H. pylori OMVs can cross the biological barriers, eventually reaching the brain. Once in the brain, these OMVs are taken up by astrocytes, which induce activation of glial cells and neuronal dysfunction, ultimately leading to exacerbated amyloid-β pathology and cognitive decline. Mechanistically, we identified a critical role for the complement component 3 (C3)-C3a receptor (C3aR) signalling in mediating the interaction between astrocytes, microglia and neurons upon the presence of gut H. pylori OMVs. Taken together, our study reveals that H. pylori has a detrimental effect on brain functionality and accelerates AD development via OMVs and C3-C3aR signalling., (© 2023 The Authors. Journal of Extracellular Vesicles published by Wiley Periodicals, LLC on behalf of the International Society for Extracellular Vesicles.)

Protein phosphatase 1 (PP1) is a key enzyme for Plasmodium development. However, the detailed mechanisms underlying its regulation remain to be deciphered. Here, we report the functional characterization of the Plasmodium berghei leucine-rich repeat protein 1 (PbLRR1), an orthologue of SDS22, one of the most ancient and conserved PP1 interactors. Our study shows that PbLRR1 is expressed during intra-erythrocytic development of the parasite, and up to the zygote stage in mosquitoes. PbLRR1 can be found in complex with PbPP1 in both asexual and sexual stages and inhibits its phosphatase activity. Genetic analysis demonstrates that PbLRR1 depletion adversely affects the development of oocysts. PbLRR1 interactome analysis associated with phospho-proteomics studies identifies several novel putative PbLRR1/PbPP1 partners. Some of these partners have previously been characterized as essential for the parasite sexual development. Interestingly, and for the first time, Inhibitor 3 (I3), a well-known and direct interactant of Plasmodium PP1, was found to be drastically hypophosphorylated in PbLRR1-depleted parasites. These data, along with the detection of I3 with PP1 in the LRR1 interactome, strongly suggest that the phosphorylation status of PbI3 is under the control of the PP1-LRR1 complex and could contribute (in)directly to oocyst development. This study provides new insights into previously unrecognized PbPP1 fine regulation of Plasmodium oocyst development through its interaction with PbLRR1.

The genus Helicobacter is composed of bacteria that colonize both the human and animal gastrointestinal tract. Helicobacter pylori infects half of the world's population, causing various disorders, such as gastritis, duodenitis and gastric cancer. Additionally, non- Helicobacter pylori Helicobacter species (NHPH) are commonly found in the stomach of pigs, dogs and cats. Most of these species have zoonotic potential and prevalence rates of 0.2-6.0%, and have been described in human patients suffering from gastric disorders undergoing a gastric biopsy. The aim of this study was to determine the occurrence of Helicobacter spp. in the stomach of patients with gastric cancer ( n = 17) and obese ( n = 63) patients. Furthermore, the outcome of the Helicobacter eradication treatment and the current infection status was evaluated. Overall, based on the genus-specific PCR followed by sequencing, DNA from Helicobacter spp. was detected in 46.3% of the patients, including single infections with H. pylori in 43.8% of the patients and mixed infections with H. pylori and canine- or feline-associated H. felis in 2.5%. About 32.5% of the patients had been subjected to previous Helicobacter eradication therapy and the triple standard therapy was the most frequent scheme (42.3%). In 48.0% of the patients who received eradication treatment, bacteria were still detected, including one mixed infection. In 23.1% of the patients who reported that a subsequent test had been performed to confirm the elimination of the bacteria, Helicobacter were still detected. In conclusion, although in a smaller percentage, NHPH may also be present in the human stomach. Thus, specific NHPH screening should be included in the diagnostic routine. The continued presence of H. pylori in the stomach of patients recently subjected to eradication schemes raises questions about the efficacy of the current Helicobacter treatments.

Malaria parasites require multiple phosphorylation and dephosphorylation steps to drive signaling pathways for proper differentiation and transformation. Several protein phosphatases, including protein phosphatase 1 (PP1), one of the main dephosphorylation enzymes, have been shown to be indispensable for the Plasmodium life cycle. The catalytic subunit of PP1 (PP1c) participates in cellular processes via dynamic interactions with a vast number of binding partners that contribute to its diversity of action. In this study, we used Plasmodium berghei transgenic parasite strains stably expressing PP1c or its inhibitor 2 (I2) tagged with mCherry, combined with the mCherry affinity pulldown of proteins from asexual and sexual stages, followed by mass spectrometry analyses. Mapped proteins were used to identify interactomes and to cluster functionally related proteins. Our findings confirm previously known physical interactions of PP1c and reveal enrichment of common biological processes linked to cellular component assembly in both schizonts and gametocytes to biosynthetic processes/translation in schizonts and to protein transport exclusively in gametocytes. Further, our analysis of PP1c and I2 interactomes revealed that nuclear export mediator factor and peptidyl-prolyl cis-trans isomerase, suggested to be essential in P. falciparum , could be potential targets of the complex PP1c/I2 in both asexual and sexual stages. Our study emphasizes the adaptability of Plasmodium PP1 and provides a fundamental study of the protein interaction landscapes involved in a myriad of events in Plasmodium , suggesting why it is crucial to the parasite and a source for alternative therapeutic strategies.

Helicobacter pylori ( H. pylori ) is a Gram-negative bacterium that infects half of the human population worldwide, causing gastric disorders, such as chronic gastritis, gastric or duodenal ulcers, and gastric malignancies. Helicobacter suis (H. suis) is mainly associated with pigs, but can also colonize the stomach of humans, resulting in gastric pathologies. In pigs, H. suis can induce gastritis and seems to play a role in gastric ulcer disease, seriously affecting animal production and welfare. Since close interactions between domestic animals, wildlife, and humans can increase bacterial transmission risk between species, samples of gastric tissue of 14 free range wild boars ( Sus scrofa ) were evaluated for the presence of H. pylori and H. suis using PCR. Samples from the antral gastric mucosa from two animals were PCR-positive for H. pylori and another one for H. suis . These findings indicate that these microorganisms were able to colonize the stomach of wild boars and raise awareness for their putative intervention in Helicobacter spp. transmission cycle.

Broad-spectrum beta-lactamase (BSBL)-producing Enterobacteriaceae impose public health threats. With increased popularity of zoos, exotic animals are brought in close proximity of humans, making them important BSBL reservoirs. However, not much is known on the presence of BSBLs in zoos in Western Europe. Fecal carriage of BSBL-producing Enterobacteriaceae was investigated in 38 zoo mammals from two Belgian zoos. Presence of bla -genes was investigated using PCR, followed by whole-genome sequencing and Fourier-transform infrared spectroscopy to cluster acquired resistance encoding genes and clonality of BSBL-producing isolates. Thirty-five putatively ceftiofur-resistant isolates were obtained from 52.6% of the zoo mammals. Most isolates were identified as E. coli (25/35), of which 64.0% showed multidrug resistance (MDR). Most frequently detected bla -genes were CTX-M-1 (17/25) and TEM-1 (4/25). Phylogenetic trees confirmed clustering of almost all E. coli isolates obtained from the same animal species. Clustering of five isolates from an Amur tiger, an Amur leopard, and a spectacled bear was observed in Zoo 1, as well as for five isolates from a spotted hyena and an African lion in Zoo 2. This might indicate clonal expansion of an E. coli strain in both zoos. In conclusion, MDR BSBL-producing bacteria were shown to be present in the fecal microbiota of zoo mammals in two zoos in Belgium. Further research is necessary to investigate if these bacteria pose zoonotic and health risks.

Gastric helicobacters ( Helicobacter ( H. ) pylori and non- H. pylori Helicobacter species (NHPHs)) colonize the stomach of humans and/or animals. Helicobacter species identification is essential since many of them are recognized as human and/or animal pathogens. Currently, Helicobacter species can only be differentiated using molecular methods. Differentiation between NHPHs using MALDI-TOF MS has not been described before, probably because these species are poorly represented in current MALDI-TOF MS databases. Therefore, we identified 93 gastric Helicobacter isolates of 10 different Helicobacter species using MALDI-TOF MS in order to establish a more elaborate Helicobacter reference database. While the MALDI Biotyper database was not able to correctly identify any of the isolates, the in-house database correctly identified all individual mass spectra and resulted in 82% correct species identification based on the two highest log score matches (with log scores ≥2). In addition, a dendrogram was constructed using all newly created main spectrum profiles. Nine main clusters were formed, with some phylogenetically closely related Helicobacter species clustering closely together and well-defined subclusters being observed in specific species. Current results suggest that MALDI-TOF MS allows rapid differentiation between gastric Helicobacter species, provided that an extensive database is at hand and variation due to growth conditions and agar-medium-related peaks are taken into account.

This study reports the comparative analyses of four Flavobacterium columnare isolates that have different virulence and antimicrobial resistance patterns. The main research goal was to reveal new insights into possible virulence genes by comparing the genomes of bacterial isolates that could induce tissue damage and mortality versus the genome of a non-virulent isolate. The results indicated that only the genomes of the virulent isolates possessed unique genes encoding amongst others a methyl-accepting chemotaxis protein possibly involved in the initial colonization of tissue, and several VgrG proteins engaged in interbacterial competition. Furthermore, comparisons of genes unique for the genomes of the highly virulent (HV) carp and trout isolates versus the, respectively, low and non-virulent carp and trout isolates were performed. An important part of the identified unique virulence genes of the HV-trout isolate was located in one particular gene region identified as a genomic island. This region contained araC and nodT genes, both linked to pathogenic and multidrug-resistance, and a luxR-gene, functional in bacterial cell-to-cell communication. Furthermore, the genome of the HV-trout isolate possessed unique sugar-transferases possibly important in bacterial adhesion. The second research goal was to obtain insights into the genetic basis of acquired antimicrobial resistance. Several point-mutations were discovered in gyrase-genes of an isolate showing phenotypic resistance towards first and second-generation quinolones, which were absent in isolates susceptible to quinolones. Tetracycline-resistance gene tetA was found in an isolate displaying acquired phenotypic resistance towards oxytetracycline. Although not localized on a prophage, several flanking genes were indicative of the gene's mobile character.

A combined agar and broth dilution method followed by qPCR was used to determine the antimicrobial susceptibility of feline H. heilmannii and H. ailurogastricus isolates. All H. ailurogastricus isolates showed a monomodal distribution of MICs for all the antimicrobial agents tested. For H. heilmannii , a bimodal distribution was observed for azithromycin, enrofloxacin, spectinomycin, and lincomycin. Single nucleotide polymorphisms (SNPs) were found in 50S ribosomal proteins L2 and L3 of the H. heilmannii isolate not belonging to the WT population for azithromycin, and in 30S ribosomal proteins S1, S7, and S12 of the isolate not belonging to the WT population for spectinomycin. The antimicrobial resistance mechanism to enrofloxacin and lincomycin remains unknown (2 and 1 H. heilmannii isolate(s), resp.). Furthermore, H. heilmannii isolates showed higher MICs for neomycin compared to H. ailurogastricus isolates which may be related to the presence of SNPs in several 30S and 50S ribosomal protein encoding genes and ribosomal RNA methyltransferase genes. This study shows that acquired resistance to azithromycin, spectinomycin, enrofloxacin, and lincomycin occasionally occurs in feline H. heilmannii isolates. As pets may constitute a source of infection for humans, this should be kept in mind when dealing with a human patient infected with H. heilmannii .

The porcine Helicobacter suis and canine-feline H. heilmannii are gastric Helicobacter species with zoonotic potential. However, little is known about the pathogenesis of human infections with these Helicobacter species. To gain more insight into the interactions of both zoonotic Helicobacter species with human gastric epithelial cells, we investigated bacterial genes that are differentially expressed in a H. suis and H. heilmannii strain after adhesion to the human gastric epithelial cell line MKN7. In vitro Helicobacter-MKN7 binding assays were performed to obtain bacterial RNA for sequencing analysis. H. suis and H. heilmannii bacteria attached to the gastric epithelial cells (i.e. cases) as well as unbound bacteria (i.e. controls) were isolated, after which prokaryotic RNA was purified and sequenced. Differentially expressed genes were identified using the DESeq2 package and SARTools pipeline in R. A list of 134 (83 up-regulated and 51 down-regulated) and 143 (60 up-regulated and 83 down-regulated) differentially expressed genes (p adj  ≤ 0.01; fold change ≥ 2) were identified for the adherent H. suis and H. heilmannii strains, respectively. According to BLASTp analyses, only 2 genes were commonly up-regulated and 4 genes commonly down-regulated in both pathogens. Differentially expressed genes of the H. suis and H. heilmannii strains belonged to multiple functional classes, indicating that adhesion of both strains to human gastric epithelial cells evokes pleiotropic adaptive responses. Our results suggest that distinct pathways are involved in human gastric colonization of H. suis and H. heilmannii. Further research is needed to elucidate the clinical significance of these findings.

The essential and distinct functions of Protein Phosphatase type 1 (PP1) catalytic subunit in eukaryotes are exclusively achieved through its interaction with a myriad of regulatory partners. In this work, we report the molecular and functional characterization of Gametocyte EXported Protein 15 (GEXP15), a Plasmodium specific protein, as a regulator of PP1. In vitro interaction studies demonstrated that GEXP15 physically interacts with PP1 through the RVxF binding motif in P. berghei. Functional assays showed that GEXP15 was able to increase PP1 activity and the mutation of the RVxF motif completely abolished this regulation. Immunoprecipitation assays of tagged GEXP15 or PP1 in P. berghei followed by immunoblot or mass spectrometry analyses confirmed their interaction and showed that they are present both in schizont and gametocyte stages in shared protein complexes involved in the spliceosome and proteasome pathways and known to play essential role in parasite development. Phenotypic analysis of viable GEXP15 deficient P. berghei blood parasites showed that they were unable to develop lethal infection in BALB/c mice or to establish experimental cerebral malaria in C57BL/6 mice. Further, although deficient parasites produced gametocytes they did not produce any oocysts/sporozoites indicating a high fitness cost in the mosquito. Global proteomic and phosphoproteomic analyses of GEXP15 deficient schizonts revealed a profound defect with a significant decrease in the abundance and an impact on phosphorylation status of proteins involved in regulation of gene expression or invasion. Moreover, depletion of GEXP15 seemed to impact mainly the abundance of some specific proteins of female gametocytes. Our study provides the first insight into the contribution of a PP1 regulator to Plasmodium virulence and suggests that GEXP15 affects both the asexual and sexual life cycle., Competing Interests: The authors have declared that no competing interests exist.

Pseudokinases play key roles in many biological processes but they are poorly understood compared to active kinases. Eight putative pseudokinases have been predicted in Plasmodium species. We selected the unique pseudokinase belonging to tyrosine kinase like (TKL) family for detailed structural and functional analysis in P. falciparum and P. berghei. The primary structure of PfpTKL lacks residues critical for kinase activity, supporting its annotation as a pseudokinase. The recombinant pTKL pseudokinase domain was able to bind ATP, but lacked catalytic activity as predicted. The sterile alpha motif (SAM) and RVxF motifs of PfpTKL were found to interact with the P. falciparum proteins serine repeat antigen 5 (SERA5) and protein phosphatase type 1 (PP1) respectively, suggesting that pTKL has a scaffolding role. Furthermore, we found that PP1c activity in a heterologous model was modulated in an RVxF-dependent manner. During the trophozoite stages, PbpTKL was exported to infected erythrocytes where it formed complexes with proteins involved in cytoskeletal organization or host cell maturation and homeostasis. Finally, genetic analysis demonstrated that viable strains obtained by genomic deletion or knocking down PbpTKL did not affect the course of parasite intra-erythrocytic development or gametocyte emergence, indicating functional redundancy during these parasite stages.

Helicobacter suis has been associated with development of gastric ulcers in the non-glandular part of the porcine stomach, possibly by affecting gastric acid secretion and altering the gastric microbiota. Fusobacterium gastrosuis is highly abundant in the gastric microbiota of H. suis-infected pigs and it was hypothesized that this micro-organism could play a role in the development of gastric ulceration. The aim of this study was to obtain further insights in the influence of a naturally acquired H. suis infection on the microbiota of the non-glandular part of the porcine stomach and in the pathogenic potential of F. gastrosuis. Infection with H. suis influenced the relative abundance of several taxa at phylum, family, genus and species level. H. suis-infected pigs showed a significantly higher colonization rate of F. gastrosuis in the non-glandular gastric region compared to non-infected pigs. In vitro, viable F. gastrosuis strains as well as their lysate induced death of both gastric and oesophageal epithelial cell lines. These gastric cell death inducing bacterial components were heat-labile. Genomic analysis revealed that genes are present in the F. gastrosuis genome with sequence similarity to genes described in other Fusobacterium spp. that encode factors involved in adhesion, invasion and induction of cell death as well as in immune evasion. We hypothesize that, in a gastric environment altered by H. suis, colonization and invasion of the non-glandular porcine stomach region and production of epithelial cell death inducing metabolites by F. gastrosuis, play a role in gastric ulceration.

With its multiple regulatory partners, the conserved Protein Phosphatase type-1 (PP1) plays a central role in many functions of the biology of eukaryotic cells, including Plasmodium falciparum . Here, we characterized a protein named PfRCC-PIP, as a major partner of PfPP1. We established its direct interaction in vitro and its presence in complex with PfPP1 in the parasite. The use of Xenopus oocyte model revealed that RCC-PIP can interact with the endogenous PP1 and act in synergy with suboptimal doses of progesterone to trigger oocyte maturation, suggesting a regulatory effect on PP1. Reverse genetic studies suggested an essential role for RCC-PIP since no viable knock-out parasites could be obtained. Further, we demonstrated the capacity of protein region containing RCC1 motifs to interact with the parasite kinase CDPK7. These data suggest that this protein is both a kinase and a phosphatase anchoring protein that could provide a platform to regulate phosphorylation/dephosphorylation processes.

The minimum inhibitory concentration of bambermycin on three porcine Helicobacter suis strains was shown to be 8 μg/mL. The effect of in-feed medication with this antibiotic on the course of a gastric infection with one of these strains, the host response and the gastric microbiota was determined in mice, as all of these parameters may be involved in gastric pathology. In H. suis infected mice which were not treated with bambermycin, an increased number of infiltrating B-cells, T-cells and macrophages in combination with a Th2 response was demonstrated, as well as a decreased parietal cell mass. Compared to this non-treated, infected group, in H. suis infected mice medicated with bambermycin, gastric H. suis colonization was not altered, but a decreased number of infiltrating T-cells, B-cells and macrophages as well as downregulated expressions of IL-1β, IL-8M, IL-10 and IFN-γ were demonstrated and the parietal cell mass was not affected. In bambermycin treated mice that were not infected with H. suis, the number of infiltrating T-cells and expression of IL-1β were lower than in non-infected mice that did not receive bambermycin. Gastric microbiota analysis indicated that the relative abundance of bacteria that might exert unfavorable effects on the host was decreased during bambermycin supplementation. In conclusion, bambermycin did not affect H. suis colonization, but decreased gastric inflammation and inhibited the effects of a H. suis infection on parietal cell loss. Not only direct interaction of H. suis with parietal cells, but also inflammation may play a role in death of these gastric acid producing cells.

Helicobacter suis is the second most prevalent Helicobacter species in the stomach of humans suffering from gastric disease. This bacterium mainly inhabits the stomach of domesticated pigs, in which it causes gastric disease, but it appears to be absent in wild boars. Interestingly, it also colonizes the stomach of asymptomatic rhesus and cynomolgus monkeys. The origin of modern human-, pig- or non-human primate-associated H. suis strains in these respective host populations was hitherto unknown. Here we show that H. suis in pigs possibly originates from non-human primates. Our data suggest that a host jump from macaques to pigs happened between 100 000 and 15 000 years ago and that pig domestication has had a significant impact on the spread of H. suis in the pig population, from where this pathogen occasionally infects humans. Thus, in contrast to our expectations, H. suis appears to have evolved in its main host in a completely different way than its close relative Helicobacter pylori in humans.

This article aimed to review the literature from 2015 dealing with gastric and enterohepatic non-Helicobacter pylori Helicobacter species (NHPH). A summary of the gastric microbiota interactions with H. pylori is also presented. An extensive number of studies were published during the last year and have led to a better understanding of the pathogenesis of infections with NHPH. These infections are increasingly reported in human patients, including infections with H. cinaedi, mainly characterized by severe bacteremia. Whole-genome sequencing appears to be the most reliable technique for identification of NHPH at species level. Presence of NHPH in laboratory animals may influence the outcome of experiments, making screening and eradication desirable. Vaccination based on UreB proteins or bacterial lysate with CCR4 antagonists as well as oral glutathione supplementation may be promising strategies to dampen the pathogenic effects associated with gastric NHPH infections. Several virulent factors such as outer membrane proteins, phospholipase C-gamma 2, Bak protein, and nickel-binding proteins are associated with colonization of the gastric mucosae and development of gastritis. The development of high-throughput sequencing has led to new insights in the gastric microbiota composition and its interaction with H. pylori. Alterations in the gastric microbiota caused by the pH-increasing effect of a H. pylori infection may increase the risk for gastric cancer., (© 2016 John Wiley & Sons Ltd.)

Background: Protein Phosphatase 1 (PP1) is an enzyme essential to cell viability in the malaria parasite Plasmodium falciparum (Pf). The activity of PP1 is regulated by the binding of regulatory subunits, of which there are up to 200 in humans, but only 3 have been so far reported for the parasite. To better understand the P. falciparum PP1 (PfPP1) regulatory network, we here report the use of three strategies to characterize the PfPP1 interactome: co-affinity purified proteins identified by mass spectrometry, yeast two-hybrid (Y2H) screening and in silico analysis of the P. falciparum predicted proteome., Results: Co-affinity purification followed by MS analysis identified 6 PfPP1 interacting proteins (Pips) of which 3 contained the RVxF consensus binding, 2 with a Fxx[RK]x[RK] motif, also shown to be a PP1 binding motif and one with both binding motifs. The Y2H screens identified 134 proteins of which 30 present the RVxF binding motif and 20 have the Fxx[RK]x[RK] binding motif. The in silico screen of the Pf predicted proteome using a consensus RVxF motif as template revealed the presence of 55 potential Pips. As further demonstration, 35 candidate proteins were validated as PfPP1 interacting proteins in an ELISA-based assay., Conclusions: To the best of our knowledge, this is the first study on PfPP1 interactome. The data reports several conserved PP1 interacting proteins as well as a high number of specific interactors to PfPP1. Their analysis indicates a high diversity of biological functions for PP1 in Plasmodium. Based on the present data and on an earlier study of the Pf interactome, a potential implication of Pips in protein folding/proteolysis, transcription and pathogenicity networks is proposed. The present work provides a starting point for further studies on the structural basis of these interactions and their functions in P. falciparum.

Human papillomavirus (HPV) infection is in the vast majority of patients accountable for the development of vulvar, cervical and vaginal intraepithelial neoplasia (VIN, CIN, VAIN); precursors of vulvar, cervical and vaginal cancers. The currently preferred treatment modality for high grade VIN, CIN and VAIN is surgical excision. Nevertheless surgical treatment is associated with adverse pregnancy outcomes and recurrence is not uncommon. The aim of this review is to present evidence on the efficacy, safety and tolerability of imiquimod (an immune response modifier) in HPV-related VIN, CIN and VAIN. A search for papers on the use of imiquimod in VIN, CIN and VAIN was performed in the MEDLINE, EMBASE and Cochrane library databases. Data was extracted and reviewed. Twenty-one articles met the inclusion criteria and were analyzed; 16 on VIN, 3 on CIN and 2 on VAIN. Complete response rates in VIN ranged from 5 to 88%. Although minor adverse effects were frequently reported, treatment with imiquimod was well tolerated in most patients. Studies on imiquimod treatment of CIN and VAIN are limited and lack uniformly defined endpoints. The available evidence however, shows encouraging effect. Complete response rates for CIN 2-3 and VAIN 1-3 ranged from 67 to 75% and 57 to 86% respectively. More randomized controlled trials on the use of imiquimod in CIN, VAIN and VIN with extended follow-up are necessary to determine the attributive therapeutic value in these patients., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background and Objectives: Epstein-Barr Virus (EBV) Latent Membrane Protein 1 (LMP1) is linked to a variety of malignancies including Hodgkin's disease, lymphomas, nasopharyngeal and gastric carcinoma. LMP1 exerts its transforming or oncogenic activity mainly through the recruitment of intracellular adapters via LMP1 C-terminal Transformation Effector Sites (TES) 1 and 2. However, LMP1 is also reported to elicit significant cytotoxic effects in some other cell types. This cytotoxic effect is quite intriguing for an oncogenic protein, and it is unclear whether both functional aspects of the protein are related or mutually exclusive., Methodology and Principal Findings: Using different ectopic expression systems in both Madin-Darby canine kidney (MDCK) epithelial cells and human embryonic kidney HEK-293 cells, we observe that LMP1 ectopic expression massively induces cell death. Furthermore, we show that LMP1-induced cytotoxicity mainly implies LMP1 C-terminal transformation effector sites and TRADD recruitment. However, stable expression of LMP1 in the same cells, is found to be associated with an increase of cell survival and an acquisition of epithelial mesenchymal transition phenotype as evidenced by morphological modifications, increased cell mobility, increased expression of MMP9 and decreased expression of E-cadherin. Our results demonstrate for the first time that the cytotoxic and oncogenic effects of LMP1 are not mutually exclusive but may operate sequentially. We suggest that in a total cell population, cells resistant to LMP1-induced cytotoxicity are those that could take advantage of LMP1 oncogenic activity by integrating LMP1 signaling into the pre-existent signaling network. Our findings thus reconcile the apparent opposite apoptotic and oncogenic effects described for LMP1 and might reflect what actually happens on LMP1-induced cell transformation after EBV infection in patients.

Background: Anemia is a characteristic of myelodysplastic syndromes, such as the rare 5q- syndrome, but its mechanism remains unclear. In particular, data are lacking on the terminal phase of differentiation of erythroid cells (enucleation) in myelodysplastic syndromes., Design and Methods: We used a previously published culture model to generate mature red blood cells in vitro from human hematopoietic progenitor cells in order to study the pathophysiology of the 5q- syndrome. Our model enables analysis of cell proliferation and differentiation at a single cell level and determination of the enucleation capacity of erythroid precursors., Results: The erythroid commitment of 5q(del) clones was not altered and their terminal differentiation capacity was preserved since they achieved final erythroid maturation (enucleation stage). The drop in red blood cell production was secondary to the decrease in the erythroid progenitor cell pool and to impaired proliferative capacity. RPS14 gene haploinsufficiency was related to defective erythroid proliferation but not to differentiation capacity., Conclusions: The 5q- syndrome should be considered a quantitative rather than qualitative bone marrow defect. This observation might open the way to new therapeutic concepts.