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Immune function shows intraspecific variation, with diet being a crucial factor that could explain such variation. Using the isotopic signature δ15N and C:N ratio, we evaluated the relationship between immune state (hemolysis and hemagglutination score) and natural variation in resource use in individuals of the species Diuca diuca. We found that some components of the immune state, specifically the hemagglutination score, correlated positively and significantly with the incorporation of animal material (high levels of δ15N), while the hemolysis score correlated positively with the C:N ratio. In this sense, we conclude that individuals of Diuca Finches that fed with a variety of prey exhibit a better immune state. [ABSTRACT FROM AUTHOR]

Background: Mean corpuscular hemoglobin concentration (MCHC) is one of the parameters detected by blood cell analyzers, often used together with mean corpuscular volume (MCV) and mean corpuscular hemoglobin content (MCH) as diagnostic indicators for anemia classification. It has important clinical value in early detection of the cause of anemia and the underlying etiology of anemia. Therefore, the accuracy of MCHC results is of great significance for the diagnosis and treatment of diseases. Methods: We reported two cases of false elevation of MCHC. Considering the possibility of cold agglutination and lipid blood interference detection, we used 37℃ water bath and plasma exchange to correct for interference on the sample. Results: After correcting the interference, MCHC returned to normal, consistent with the patient's disease status. Therefore, the two cases of abnormal elevation of MCHC are considered to be pseudo elevation caused by interference. Conclusions: For specimens with abnormally elevated MCHC levels, experimenters should first analyze possible interfering factors and choose effective methods to correct different interferences, providing accurate testing reports for doctors and patients. [ABSTRACT FROM AUTHOR]

Galectins are a family of beta-galactoside-binding proteins that are characterised by their carbohydrate recognition domain (CRD) and include galectin-1 and galectin-3. These galectins have been implicated in numerous diseases due to their pleiotropic nature, including cancer and fibrosis, with therapeutic inhibitors being clinically developed to block the CRD. One of the early methods developed to characterise these galectins was the hemagglutination of red blood cells. Although it is insightful, this approach has been hampered by a lack of sensitivity and accurate quantification of the agglutination observed. In this study, we aimed to validate a more precise and quantitative method to enable the further investigation of differences between galectins in respect to agglutination induction in different blood groups, as well as the characterisation of small molecule inhibitors. Quantification of hemagglutination was shown to be optimal using U-bottom plates imaged and analysed with FIJI ImageJ rather than flat-bottom plates read for absorbance on an optical density plate reader. Galectin-3-induced red blood cell agglutination efficacy increased significantly from blood group O to A to B. However, for both the galectin-1 monomer and concatemer, a more comparable effect was observed between blood group B and O, but with more potent effects than in blood group A. Inhibition assays for both galectin-3 and galectin-1 induced-hemagglutination were able to demonstrate clear concentration responses and expected selectivity profiles for a set of small-molecule glycomimetics, confirming the historical profiles obtained in biochemical binding and functional cellular assays. [ABSTRACT FROM AUTHOR]

Background: This study aimed to explore the regulatory effect of anserine on HUVEC cell injury and thrombosis in deep venous thrombosis (DVT) rats, and to elucidate the underlying molecular mechanisms. Methods: Non-targeted metabolomics data analyses were conducted using an ultra-performance liquid chromatography system Vanquish UHPLC and mass spectrometer to detect plasma metabolism profiles. The transcriptome sequencing and gene intervention experiments were performed to verify the regulatory effect. Further in vivo and in vitro experiments were performed. Enzyme-linked immunosorbent assay was used to detect the levels of P-selectin, E-selectin, and vWF, hematoxylin-eosin (HE) staining was performed to observe thrombotic and inflammatory cell infiltration, flow cytometry and TUNEL assays were performed to detect apoptosis, and qPCR and WB assays were conducted to determine the gene and protein expression. Results: Anserine alleviated HUVECs injury, reduced adhesion molecule expression, and inflammation. It decreased P-selectin, E-selectin, vWF, THBD, TFPI levels, and apoptosis while promoting NOS3, ET-1, and NO release in HUVECs. In DVT rats, anserine reduced P-selectin, E-selectin, vWF, thrombosis, cell infiltration, apoptosis, and promoted NO release. Transcriptome sequencing and gene intervention confirmed anserine's regulation of the PI3K-Akt pathway and coagulation via MYB. CARNMT1, a regulatory enzyme for anserine metabolism, increased anserine content, inhibiting coagulation, thrombosis, cell infiltration, and promoting NO release in rats. Conclusion: This study confirmed anserine could alleviate DVT by improving the inflammatory response, inhibiting blood agglutination, and promoting vasodilation, providing new potential therapeutic targets, important scientific evidence for the development of DVT management, and new clues for an indepth understanding of its molecular mechanisms. [ABSTRACT FROM AUTHOR]

Through enabling whole blood detection in point-of-care testing (POCT), sedimentation-based plasma separation promises to enhance the functionality and extend the application range of lateral flow assays (LFAs). To streamline the entire process from the introduction of the blood sample to the generation of quantitative immune-fluorescence results, we combined a simple plasma separation technique, an immunoreaction, and a micropump-driven external suction control system in a polymer channel-based LFA. Our primary objective was to eliminate the reliance on sample-absorbing separation membranes, the use of active separation forces commonly found in POCT, and ultimately allowing finger prick testing. Combining the principle of agglutination of red blood cells with an on-device sedimentation-based separation, our device allows for the efficient and fast separation of plasma from a 25-µL blood volume within a mere 10 min and overcomes limitations such as clogging, analyte adsorption, and blood pre-dilution. To simplify this process, we stored the agglutination agent in a dried state on the test and incorporated a filter trench to initiate sedimentation-based separation. The separated plasma was then moved to the integrated mixing area, initiating the immunoreaction by rehydration of probe-specific fluorophore-conjugated antibodies. The biotinylated immune complex was subsequently trapped in the streptavidin-rich detection zone and quantitatively analyzed using a fluorescence microscope. Normalized to the centrifugation-based separation, our device demonstrated high separation efficiency of 96% and a yield of 7.23 µL (= 72%). Furthermore, we elaborate on its user-friendly nature and demonstrate its proof-of-concept through an all-dried ready-to-go NT-proBNP lateral flow immunoassay with clinical blood samples. [ABSTRACT FROM AUTHOR]

Background: Cold agglutinins (CAs) in blood samples can cause a reversible agglutination of red blood cell (RBC) which result in an incorrect complete blood count (CBC). So, it is important to explore new simple and feasible treatment conditions for clinical work. Methods: The CAs group included 32 samples with CAs. The parameters of CBC at room temperature or after prewarming at 37°C or 41°C for different time periods were compared. The consistency and correlation of those parameters were analyzed. The morphology of erythrocytes in the CAs group was observed manually. The control group included 45 samples without CAs and prewarmed at 37°C or 41°C for different time periods. The differences were also analyzed. Results: CAs have a significant effect on CBC. After prewarming at 37°C or 41°C the interferences are all corrected. Consider prewarming at 37°C for 120 minutes as the standard procedure. The consistency and correlation analysis showed there was no statistical difference between the results of each subgroup and standard group, except the MCHC of group 41°C 10 minutes. The correlation of parameters between all subgroups and the standard group is satisfied. Microscopic examination showed no RBC aggregation or fragmentation after prewarming at 41°C or 37°C. According to the maximum bias requirements for expert performance in Validation, Verification, and Quality Assurance of Automated Hematology Analyzers, 2nd Edition (CLSI H26-A2), the differences in over-all results in control group are negligible. Conclusions: The 41°C 2 minutes prewarming method is a rapid and effective way for treating samples with CAs. It is an efficient way to obtain more reliable CBC results, without specific instruments. [ABSTRACT FROM AUTHOR]

Brucellosis is a zoonotic disease that causes enormous losses in livestock production worldwide and has a significant public health impact. None of the brucellosis-free countries is currently able to guarantee their ability to prevent the introduction of the pathogen due to the increase in tourism and the expansion of migration. The timely identification of infected animals is an effective means of preventing brucellosis and minimizing the epidemiological risk. The tube agglutination test, Rose Bengal plate test, complement fixation test, and enzyme-linked immunosorbent assay, which are routinely used to identify seropositive productive animals, have limitations and results that do not always correlate. The indirect hemagglutination assay (IHA) stands out among non-traditional methods because it is affordable, has a simple protocol, and is more reliable than classical serological tests, especially in cases of questionable and/or false-negative results. The diagnostic value of the IHA has long been studied by laboratories in several countries, but mostly by post-soviet research teams; therefore, the results continue to be published in Russian-language journals, ensuring that the local scientific community can access the results. In addition, the efficacy of this test for the diagnosis of brucellosis and other infectious diseases has not yet been reviewed. The purpose of this review was to summarize the results of studies on the development and use of IHA for the diagnosis of brucellosis and to determine the prospects for further improvement. [ABSTRACT FROM AUTHOR]

Methicillin-resistant Staphylococcus aureus (MRSA) is a common resistant bacterium, whose resistance has expanded to commonly used antibiotics. It is crucial to create novel treatments to tackle bacterial resistance. Trans-resveratrol and curcumin are naturally occurring phenolic compounds, whose effects on MRSA virulence are the subject of this investigation. Sub-MICs of trans-resveratrol and curcumin were tested on the virulence factors of 50 MRSA clinical isolates (CIs), including biofilm, hemolysin, hemagglutination, protease, and lecithinase. The distribution of the virulence factors of the CIs was as follows: hemolysin: 98%, hemagglutination: 70%, protease: 62%, biofilm: 56%, and lecithinase: 52%. The sub-MIC that could reduce the effect of the tested virulence factors by 50% or more (IC50) was observed in the strains that showed susceptibility to the individual administration of trans-resveratrol at 50 µg/mL and curcumin at 20 µg/mL. Hemagglutination and hemolysin activity were inhibited by at least 50% in the majority of CIs (57–94%). Meanwhile, the IC50 for protease and biofilm was observed in 6.5–17.8% of the CIs. A few of the CIs were susceptible to lecithinase inhibition, but all showed a full inhibition. This research supports the possibility of the use of these compounds to reduce the bacterial virulence that can reduce antibiotic utilization, and eventually, they can become a potential alternative treatment in combating bacterial resistance. [ABSTRACT FROM AUTHOR]

The H9N2 avian influenza virus (AIV) represents a significant risk to both the poultry industry and public health. Our surveillance efforts in China have revealed a growing trend of recent H9N2 AIV strains exhibiting a loss of hemagglutination activity at 37°C, posing challenges to detection and monitoring protocols. This study identified a single K141N substitution in the hemagglutinin (HA) glycoprotein as the culprit behind this diminished hemagglutination activity. The study evaluated the evolutionary dynamics of residue HA141 and studied the impact of the N141K substitution on aspects such as virus growth, thermostability, receptor-binding properties, and antigenic properties. Our findings indicate a polymorphism at residue 141, with the N variant becoming increasingly prevalent in recent Chinese H9N2 isolates. Although both wild-type and N141K mutant strains exclusively target a, 2-6 sialic acid receptors, the N141K mutation notably impedes the virus's ability to bind to these receptors. Despite the mutation exerting minimal influence on viral titers, antigenicity, and pathogenicity in chicken embryos, it significantly enhances viral thermostability and reduces plaque size on Madin-Darby canine kidney (MDCK) cells. Additionally, the N141K mutation leads to decreased expression levels of HA protein in both MDCK cells and eggs. These findings highlight the critical role of the K141N substitution in altering the hemagglutination characteristics of recent H9N2 AIV strains under elevated temperatures. This emphasizes the need for ongoing surveillance and genetic analysis of circulating H9N2 AIV strains to develop effective control and prevention measures. IMPORTANCE The H9N2 subtype of avian influenza virus (AIV) is currently the most prevalent low-pathogenicity AIV circulating in domestic poultry globally. Recently, there has been an emerging trend of H9N2 AIV strains acquiring increased affinity for humantype receptors and even losing their ability to bind to avian-type receptors, which raises concerns about their pandemic potential. In China, there has been a growing number of H9N2 AIV strains that have lost their ability to agglutinate chicken red blood cells, leading to false-negative results during surveillance efforts. In this study, we identified a K141N mutation in the HA protein of H9N2 AIV to be responsible for the loss of hemagglutination activity. This finding provides insight into the development of effective surveillance, prevention, and control strategies to mitigate the threat posed by H9N2 AIV to both animal and human health. [ABSTRACT FROM AUTHOR]

This article discusses the importance of accurately identifying rare blood types in clinical laboratories to prevent life-threatening transfusion reactions. The B3 phenotype, which is characterized by weak expression of B antigens, is particularly challenging to identify and is often misdiagnosed. The article presents a case study where a B3 phenotype was initially misidentified as para-Bombay due to a lack of laboratory practices and experience. The authors emphasize the need for rigorous training and adherence to standard operating procedures to improve the accuracy of blood type determinations and enhance patient safety. [Extracted from the article]

The present study describes the case of a 52-year-old male patient who presented with subacute onset dysarthria and oral-facial-lingual dyskinesia, with normal blood glucose and acanthocyte levels, and no history of drug use. The patient tested negative for autoimmune encephalitis-related antibodies and paraneoplastic-related antibodies. The level of cerebrospinal fluid (CSF) protein was slightly elevated, and the Treponema pallidum hemagglutination assay and rapid plasma reagin test were positive in both serum and CSF samples. After 1 month of treatment with doxycycline, the patient's oral-facial-lingual dyskinesia was significantly improved, suggesting the diagnosis of neurosyphilis. [ABSTRACT FROM AUTHOR]

Background: Avian Escherichia coli (E.coli) type 1 fimbriae adhere to avian tracheal epithelial cells through the FimH protein. However, the adhesion-related antigen is still unknown. The purpose of this study was to analyze the antigenicity of the type 1 fimbrial FimH protein of wild-type avian E. coli, screen antigen epitopes, and prepare monoclonal antibodies (mAbs) that can block the adhesion of avian E. coli. Results: In this study, the nucleic acid homologies of MG2 (O11), TS12 (O18), and YR5 (O78) with K12 were 97.7%, 99.6%, and 97.7%, respectively, and the amino acid sequence similarity reached 98.7%, 99.3%, and 98.0%, respectively. The epitopes and hydrophilicities of the FimH proteins of these three strains were similar. The more obvious lectin domain epitopes were located at FimH protein positions 111–124 and 154–162. The mAbs 7C2 and 7D8 against these two epitopes were prepared. An adhesion inhibition test showed that 7C2 and 7D8 blocked bacterial adhesion to avian tracheal epithelial cells. The mAb 7C2 against the 111–124 epitope inhibited O78 strain adhesion by 93%, and the mAb 7D8 against the 154–162 epitope inhibited O78 strain adhesion by 49%, indicating that these two epitopes are closely related to the adhesion of type 1 fimbriae. However, only the 111–124 epitope-recognizing mAb 7C2 inhibited bacterial agglutination of erythrocytes, indicating that host cell receptor binding and erythrocyte agglutination are not mediated by the same spatial locations within the FimH protein. Conclusions: The results demonstrate that the mAbs 7C2 and 7D8 against FimH protein positions 111–124 and 154–162 could inhibit the adhesion of E.coli to the chicken trachea. [ABSTRACT FROM AUTHOR]

Abstract—As an alternative to the classical method of erythrocyte hemagglutination, a latex agglutination assay based on the interaction of influenza viruses with the sialoglycoprotein fetuin immobilized on the surface of polystyrene microspheres has been developed. Twelve influenza A virus strains of different subtypes and two influenza B viruses of different lines were tested. Simultaneous titration of viruses using the classical hemagglutination test and the proposed latex agglutination assay showed similar sensitivity and a high degree of correlation (R = 0.94). The obtained microspheres can be used for titration of viruses that recognize and bind sialylated glycans as receptors. In particular, latex aggregation was also induced by the Newcastle disease virus. [ABSTRACT FROM AUTHOR]

Newcastle disease (ND), caused by the virulent Newcastle disease virus (NDV), is an acute, highly contagious, and economically significant avian disease worldwide. Vaccination is the most effective measure for controlling ND. In recent years, vaccines matched with the prevalent strains of genotype VII have been developed and are now commercially available. These vaccines can provide full protection for chickens against clinical disease and mortality after challenges with genotype VII viruses and significantly decrease virus shedding compared to conventional vaccines belonging to genotypes I and II. Vaccinated hens can transfer antibodies to their offspring through the egg yolk. Maternally derived antibodies can provide passive protection against diseases but can also interfere with vaccination efficacy early in life. This study was conducted on chicks hatched from hens vaccinated with a commercial genotype VII NDV-matched vaccine to investigate the correlation between hemagglutination inhibition (HI) antibody levels in chicks and hens and the decaying pattern of maternally derived HI antibodies, and to evaluate the protective efficacy of different levels of maternally derived HI antibodies against challenge with a virulent NDV strain of genotype VII based on survivability and virus shedding. The HI antibody titers in chicks at hatching were about 1.3 log2 lower than those in hens, indicating an antibody transfer rate of approximately 41.52%. The estimated half-life of these antibodies was about 3.2 days. The protective efficacy of maternally derived HI antibodies was positively correlated with the titer. These antibodies could effectively protect chicks against mortality when the titer was 7 log2 or higher, but they were unable to prevent virus shedding or infection even at a high titer of 11 log2. The obtained results will greatly assist producers in determining the immune status of chicks and formulating appropriate vaccination schedules against ND. [ABSTRACT FROM AUTHOR]

Haemorrhagic septicaemia (HS) is a highly contagious and fatal disease of cattle and buffaloes and causes major economic losses to farmers. Though indirect hemagglutination (IHA) test has been used to detect a specific antibody against P. multocida, it has low specificity for sero-diagnosis of HS. Therefore, development of a rapid, highly sensitive and specific serological test is a prerequisite for detection of antibodies against HS. In this context, we explored an in-house ELISA method using recombinant antigens for detection of antibodies against P. multocida in bovines. nanH gene from P. multocida B:2 strain P52 was cloned and the recombinant mature protein with a C- and N-terminal truncation was produced as a fusion protein (~63 kDa) in Escherichia coli. The immunogenic potential of purified rNanH-Tr was assessed by the Western blot method using specific anti-rNanH-Tr antibody responses in sera collected from immunized rabbits. An indirect-ELISA based on rNanH-Tr was developed and optimized. Furthermore, the rNanH-Tr ELISA was applied to screen bovine serum samples (n=250). The receiver operating characteristic curve analysis for the detection of anti P. multocida specific antibodies indicated a diagnostic sensitivity of 86.2 (CI 73.26-96.80%) and specificity of 80.0 (63.06-91.56%). No cross reactivity was noted with antibodies against other bovine diseases (e.g., foot-and-mouth disease and brucellosis). Screening of random bovine serum samples showed a 22% sero-positivity for anti P. multocida specific antibodies. [ABSTRACT FROM AUTHOR]

Cold agglutinins are commonly identified in transfusion laboratories and are defined by their ability to agglutinate erythrocytes at 3–4°C, with most demonstrating a titer >64. Similarly, cryoglobulins can precipitate from plasma when temperatures drop below central body temperature, resulting in erythrocyte agglutination. Thankfully, disease associated from these autoantibodies is rare, but unfortunately, such temperature ranges are routinely encountered outside of the body's circulation, as in an extracorporeal circuit during hematopoietic progenitor cell (HPC) collection or human cell therapy laboratory processing. When agglutination occurs ex vivo , complications with the collection and product may be encountered, resulting in adverse events or product loss. Here, we endeavor to share our experience in preventing and responding to known cases at risk of or spontaneous HPC agglutination in our human cell therapy laboratory. Four cases of HPC products at risk for, or spontaneously, agglutinating were seen at our institution from 2018 to 2020. Planned modifications occurred, including ambient room temperature increases, tandem draw and return blood warmers, warm product transport and extended post-thaw warming occurred. In addition, unplanned modifications were undertaken, including warm HPC product processing and plasma replacement of the product when spontaneous agglutination of the product was identified. All recipients successfully engrafted after infusion. While uncommon, cold agglutination of HPC products can disrupt standard processes of collection and processing. Protocol modifications can circumvent adverse events for the donor and minimize product loss. Such process modifications should be considered in individuals with known risks for agglutination going to HPC donation/collection. [ABSTRACT FROM AUTHOR]

Hemagglutination assay has been used for blood typing and detecting viruses, thus applicable for the diagnosis of infectious diseases, including COVID-19. Therefore, the development of microfluidic devices for fast detection of hemagglutination is on-demand for point-of-care diagnosis. Here, we present a way to detect hemagglutination in 3D microfluidic devices via optical absorbance (optical density, OD) characterization. 3D printing is a powerful way to build microfluidic structures for diagnostic devices. However, mixing liquid in microfluidic chips is difficult due to laminar flow, which hampers practical applications such as antigen-antibody mixing. To overcome the issue, we fabricated 3D microfluidic chips with embedded microchannel and microwell structures to induce hemagglutination between red blood cells (RBCs) and antibodies. We named it a 3D microtrap chip. We also established an automated measurement system which is an integral part of diagnostic devices. To do this, we developed a novel way to identify RBC agglutination and non-agglutination via the OD difference. By adapting a 3D-printed aperture to the microtrap chip, we obtained a pure absorbance signal from the microchannels by eliminating the background brightness of the microtrap chip. By investigating the underlying optical physics, we provide a 3D device platform for detecting hemagglutination. [ABSTRACT FROM AUTHOR]

Avibacterium paragallinarum is an important respiratory pathogen of domestic chickens. Avibacterium paragallinarum has been subtyped into three serogroups and nine serovars according to the Page and revised Kume schemes. The major hemagglutinin antigen of A. paragallinarum is HMTp210, which is a large protein of about 2000 amino acids (aa), including a 70-aa signal peptide at its N-terminal end. However, the regions important for the hemagglutination (HA) activity and serotypes of HMTp210 remain unclear. In this study we constructed a series of A. paragallinarum strains expressing HMTp210 in-frame deletion mutants and determined their HA titers to identify the regions important for the HA activity and serotypes of HMTp210. Two distinct types of HA activities were found in HMTp210. The type 1 HA activity resided in the region spanning the full-length HA (aa 71–2084), whereas the type 2 resided in the region spanning aa 1003–2084. The putative ligand binding of the type 1 HA activity was located at aa 176–360, which had a structure similar to YadA of Yersinia enterocolitica. The putative ligand binding site of the type 2 HA activity was located at aa 1003–1125, which had a structure similar to UspA1 from Moraxella catarrhalis. The type 1 HA activity appeared to be Page serogroup specific, whereas type 2 appeared to be Kume serovar specific. Finally, sequence analyses of the regions spanning aa 1–400 and aa 1100–1600 of HMTp210 could be useful for the molecular serotyping (the Page and revised Kume schemes) of A. paragallinarum isolates. Regiones importantes para la actividad de hemaglutinación y serotipos de la proteína HMTp210 de Avibacterium paragallinarum. La bacteria Avibacterium paragallinarum es un patógeno respiratorio importante de los pollos domésticos. Avibacterium paragallinarum se subtipificó en tres serogrupos y nueve serovares de acuerdo con los esquemas revisados de Page y Kume. El principal antígeno de la hemaglutinina de A. paragallinarum es la proteína HMTp210, que es una proteína grande de unos 2000 aminoácidos (aa), que incluye un péptido señal de 70 aminoácidos en su extremo N-terminal. Sin embargo, las regiones importantes para la actividad de hemaglutinación (HA) y de los serotipos de la proteína HMTp210 siguen sin estar determinados. En este estudio, se construyó una serie de cepas de A. paragallinarum que expresaban mutantes de deleción en marco de lectura de HMTp210 y se determinaron sus títulos de hemaglutinación para identificar las regiones importantes para la actividad de hemaglutinación y de los serotipos de HMTp210. Se encontraron dos tipos distintos de actividades hemaglutinación en la proteína HMTp210. La actividad de hemaglutinación de tipo 1 residía en la región que abarcaba la longitud completa (aminoácidos 71–2084), mientras que la de tipo 2 residía en la región que abarcaba entre los aminoácidos 1003–2084. El sitio supuesto de unión al ligando de la actividad de hemaglutinación tipo 1 se ubicó entre los aminoácidos 176–360, que tenía una estructura similar a la proteína YadA de Yersinia enterocolitica. El supuesto sitio de unión del ligando de la actividad de hemaglutinación tipo 2 se ubicó entre los aminoácidos 1003–1125, que tenía una estructura similar a la proteína UspA1 de Moraxella catarrhalis. La actividad de hemaglutinación tipo 1 parecía ser específica del serogrupo Page, mientras que la hemaglutinación tipo 2 parecía ser específica del serovar Kume. Finalmente, los análisis de secuencias de las regiones que abarcan los aminácidos 1–400 y aminoácidos 1100–1600 de HMTp210 podrían ser útiles para la serotipificación molecular (por el esquema revisado de Page y Kume revisado) de aislamientos de A. paragallinarum. [ABSTRACT FROM AUTHOR]

Hemolysin II (HlyII) is one of the virulence factors of the opportunistic bacterium Bacillus cereus belonging to the group of β-pore-forming toxins. This work created a genetic construct encoding a large C-terminal fragment of the toxin (HlyIILCTD, M225–I412 according to the numbering of amino acid residues in HlyII). A soluble form of HlyIILCTD was obtained using the SlyD chaperone protein. HlyIILCTD was first shown to be capable of agglutinating rabbit erythrocytes. Monoclonal antibodies against HlyIILCTD were obtained by hybridoma technology. We also proposed a mode of rabbit erythrocyte agglutination by HlyIILCTD and selected three anti-HlyIILCTD monoclonal antibodies that inhibited the agglutination. [ABSTRACT FROM AUTHOR]

Newcastle disease virus (NDV) sub-genotype VII.1.1 is the most common circulating NDV in Iran. In this study, a velogenic NDV isolate was plaque purified and then characterized according to Office International des Epizooties (OIE) standard protocols. The biological properties of the purified isolate named CH/RT40/IR/2011 were characterized using sequencing and phylogenetic analysis, measurement of pathogenicity indexes and challenge studies. The isolate was plaque purified on chicken embryo fibroblast cells for three rounds and then characterized using molecular and biological approaches. Phylogenetic and evolutionary distance analysis of fusion and hemagglutinin-neuraminidase genes classified the virus in sub-genotype VII.1.1. No mutation was observed in the glycosylation and neutralizing epitope sites of the fusion and hemagglutinin-neuraminidase proteins compared to other reported Iranian NDV VII.1.1 isolates. The presence of the 112RRQKRF117 motif in the fusion protein cleavage site together with mean death time, intracerebral pathogenicity index and intravenous pathogenicity index of 57 hr, 1.80 and 2.50 respectively, revealed that the RT40 isolate was a velogenic NDV. In the challenge study, all chickens were inoculated via eye drop, and intranasal route with RT40 isolate died within a week. While all chickens in the vaccinated and challenged group survived and showed no clinical signs. In conclusion, according to genetic analysis, pathotyping and challenge study, the RT40 isolate was similar to virulent NDVs in Iran and was a suitable candidate for a national standard challenge strain, vaccine trials and vaccine production in commercial levers. [ABSTRACT FROM AUTHOR]

Six swine coronaviruses (SCoVs), which include porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), porcine hemagglutination encephalomyelitis virus (PHEV), porcine respiratory coronavirus (PRCV), swine acute diarrhea syndrome coronavirus (SADS-CoV), and porcine delta coronavirus (PDCoV), have been reported as infecting and causing serious diseases in pigs. To investigate the genetic diversity and spatial distribution of SCoVs in clinically healthy pigs in China, we collected 6400 nasal swabs and 1245 serum samples from clinically healthy pigs at slaughterhouses in 13 provinces in 2017 and pooled them into 17 libraries by type and region for next-generation sequencing (NGS) and metavirome analyses. In total, we identified five species of SCoVs, including PEDV, PDCoV, PHEV, PRCV, and TGEV. Strikingly, PHEV was detected from all the samples in high abundance and its genome sequences accounted for 75.28% of all coronaviruses, while those belonging to TGEV (including PRCV), PEDV, and PDCoV were 20.4%, 2.66%, and 2.37%, respectively. The phylogenetic analysis showed that two lineages of PHEV have been circulating in pig populations in China. We also recognized two PRCVs which lack 672 nucleotides at the N-terminus of the S gene compared with that of TGEV. Together, we disclose preliminarily the genetic diversities of SCoVs in clinically healthy pigs in China and provide new insights into two SCoVs, PHEV and PRCV, that have been somewhat overlooked in previous studies in China. [ABSTRACT FROM AUTHOR]

Human influenza A/H2N2 can induce a pandemic in the future. This study evaluated the hemagglutination inhibition and neutralizing titers of intravenous immunoglobulin against A/H2N2 viruses, indicating the status of the donor population. In this study, the antibody titers decreased during the study period—2012–2021—suggesting a reduction in the immunity of the studied population. [ABSTRACT FROM AUTHOR]

BACKGROUND: In pretransfusion blood typing, pretreatments such as centrifugation and suspension of red blood cells (RBCs) and mixing them with sufficient amounts of reagents are required, but these steps are time-consuming and costly. OBJECTIVE: Aiming to develop a new blood typing method that requires no dilution and only a small amount of reagent, we attempted to determine blood type using syllectometry, an easy-to-use and rapid optical method for measuring the RBC aggregation that occurs when blood flow is abruptly stopped in a flow channel. METHODS: Samples of whole blood from 20 healthy participants were mixed with antibody reagents for blood typing at mixing ratios of 2.5% to 10% and measured with a syllectometry device. RESULTS: Amplitude (AMP), one of the aggregation parameters, showed significant differences between agglutination and non-agglutination samples at mixing ratios from 2.5% to 10%. Although there were significant individual differences in aggregation parameters, calculation of AMP relative to that of blood before reagent mixing reduced the individual differences and enabled determination of blood type in all participants. CONCLUSIONS: This new method enables blood typing with a small amount of reagent, without the time-consuming and labor-intensive pretreatments such as centrifugation and suspension of RBCs. [ABSTRACT FROM AUTHOR]

The disease is linked to an underlying BM-based clonal B-cell proliferation.[[3]] Cases associated with overt lymphoma, in particular lymphoplasmacytic lymphoma (LPL), or infections are excluded from the pCAD category and are considered secondary cold agglutinin syndromes. PCAD diagnosis needs appropriate correlation of clinical and laboratory findings with bone marrow histology and molecular data. When clinical and laboratory findings are suggestive of pCAD and BM histology shows a low-grade clonal B-cell infiltrate, the mutational analysis of I MYD88 i status is mandatory to exclude an LPL. [Extracted from the article]

Experimental findings for SARS-CoV-2 related to the glycan biochemistry of coronaviruses indicate that attachments from spike protein to glycoconjugates on the surfaces of red blood cells (RBCs), other blood cells and endothelial cells are key to the infectivity and morbidity of COVID-19. To provide further insight into these glycan attachments and their potential clinical relevance, the classic hemagglutination (HA) assay was applied using spike protein from the Wuhan, Alpha, Delta and Omicron B.1.1.529 lineages of SARS-CoV-2 mixed with human RBCs. The electrostatic potential of the central region of spike protein from these four lineages was studied through molecular modeling simulations. Inhibition of spike protein-induced HA was tested using the macrocyclic lactone ivermectin (IVM), which is indicated to bind strongly to SARS-CoV-2 spike protein glycan sites. The results of these experiments were, first, that spike protein from these four lineages of SARS-CoV-2 induced HA. Omicron induced HA at a significantly lower threshold concentration of spike protein than the three prior lineages and was much more electropositive on its central spike protein region. IVM blocked HA when added to RBCs prior to spike protein and reversed HA when added afterward. These results validate and extend prior findings on the role of glycan bindings of viral spike protein in COVID-19. They furthermore suggest therapeutic options using competitive glycan-binding agents such as IVM and may help elucidate rare serious adverse effects (AEs) associated with COVID-19 mRNA vaccines, which use spike protein as the generated antigen. [ABSTRACT FROM AUTHOR]

Glycerol is seen in biological systems as an intermediate in lipid metabolism. In recent years, glycerol has been reported to act as a chemical chaperone to correct the conformation of proteins. Here, we investigate the role of glycerol in galectin-7 (Gal-7). The thermal shift and CD assays showed that the thermal stability of Gal-7 increased with glycerol concentration but with little secondary structure changes induced by glycerol. In addition, glycerol can inhibit Gal-7-mediated erythrocyte agglutination. We also solved the crystal structures of human Gal-7 in complex with glycerol in two different conditions. Glycerol binds at the carbohydrate-recognition binding sites of Gal-7, which indicates glycerol as a small ligand for Gal-7. Surprisingly, glycerol can bind a new pocket near the N-terminus of Gal-7, which can greatly reduce the flexibility and improve the stability of this region. Moreover, overexpression of Gal-7 decreased the intracellular triglyceride levels and increased mRNA expression of aquaporin-3 (AQP-3) when HeLa cells were incubated with glycerol. These findings indicate that Gal-7 might regulate glycerol metabolism. Overall, our results on human Gal-7 raise the perspective to systematically explore this so far unrecognized phenomenon for Gal-7 in glycerol metabolism. [ABSTRACT FROM AUTHOR]

Copyright of Acta Vet Indones. The Indonesian Veterinary Journal / Jurnal Acta Veterinaria Indonesiana is the property of IPB University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study was to assess the lot-to-lot consistency, immunogenicity and safety of three manufacturing lots of a quadrivalent inactivated influenza vaccine (IIV4). A randomized, double-blind, phase IV clinical trial was conducted in healthy children, adolescents and adults aged 9–59 years in Guizhou Province, China. Eligible participants were enrolled and randomized into three groups in a ratio of 1:1:1 to receive a single dose of one of three manufacturing lots of IIV4. Serum samples were collected before and 28 days after vaccination for hemagglutination inhibition (HI) antibody testing. Safety data were collected for up to 28 days after vaccination. The primary objective was to evaluate the lot-to-lot consistency of immune response as assessed by the geometric mean titer (GMT) of HI antibody at 28 days after vaccination. Between November 27, 2022 and December 18, 2022, 1260 eligible participants were enrolled, with similar participant demographics among groups. Immune responses after vaccination were comparable across groups, with the 95% confidence intervals (CIs) of GMT ratios for all 4 strains falling into the equivalence criterion of (0.67, 1.5). The seroconversion rates (SCRs) and seroprotection rates (SPRs) met the US Center or Biologics Evaluation and Research (CBER) criteria for all strains for each lot (lower limit of 95% CI of SCR ≥ 40% and SPR ≥ 70%). The incidences of solicited and unsolicited adverse reactions were similar among three groups, most of which (91.9%) were mild or moderate in severity. A total of 11 serious adverse events were reported during the study, and all were considered unrelated to vaccination. The three manufacturing lots of IIV4 demonstrated consistent immunogenicity. IIV4 can elicit satisfactory immune responses for all four strains and no safety concerns were identified. Clinical trial registration: Identifier No. NCT05512494. • The first lot-to-lot consistency study to demonstrate the stability of manufacturing process. • The first study to prove that IIV4 has good immunogenicity and safety in multi-ethnic population, such as Dong and Miao, other than Han in China. • IIV4 could induce good immune response in both adolescents and adults. • Vaccination with IIV4 did not increase additional safety risk. [ABSTRACT FROM AUTHOR]

Influenza seasons occur annually, building immune history for individuals, but the influence of this history on subsequent influenza vaccine protection remains unclear. We extracted data from an animal trial to study its potential impact. The trial involved 80 ferrets, each receiving either one type of infection or a placebo before vaccination. We quantified the vaccine protection by evaluating hemagglutination inhibition (HAI) antibody titer responses. We tested whether hosts with different infection histories exhibited similar level of responses when receiving the same vaccine for all homologous and heterologous outcomes. We observed that different pre-existing immunities were generally beneficial to vaccine induced responses, but varied in magnitude. Without pre-immunity, post-vaccination HAI titers after the 1st dose of the vaccine were less likely to be above 1:40, and a booster shot was needed. Our study suggests that pre-existing immunity may strengthen and extend the homologous and heterologous vaccine responses. [ABSTRACT FROM AUTHOR]

We explored the potential for a biphasic pattern in waning of antibody titers after influenza vaccination. We collected blood samples in a randomized controlled trial of influenza vaccination in children and tested them with hemagglutination inhibition assays for influenza A(H3N2) and influenza B/Victoria lineage. Using piecewise log-linear mixed-effects models, we found evidence for a faster initial waning of antibody titers for the first 1-2 years after vaccination and then slower longer-term declines. Children with higher postvaccination titers had faster antibody decay. [ABSTRACT FROM AUTHOR]

Currently, duck Tembusu virus (DTMUV), an emerging avian pathogenic flavivirus, is widely spread and becomes endemic in duck populations in Asia, causing significant economic losses in the duck producing industry. To early detection and control of DTMUV, the well‐validated diagnostic tests for efficient detection of DTMUV infection in ducks are needed. In this study, we validated and compared hemagglutination inhibition (HI) and indirect immunofluorescence (IFA) tests for identifying antibodies against DTMUV in duck serum samples. Our results demonstrated that HI and IFA tests can both be used to detect antibodies against DTMUV in duck serum samples with high sensitivity (100%), specificity (>87%) and overall agreement with the gold standard serum neutralization (SN) test (>90%). Additionally, DTMUV‐specific antibody titres determined by HI and IFA tests correlated well with the neutralizing antibody titres obtained by SN test. No cross‐reactivity against common duck viruses and other flaviviruses was observed in both tests. It is interesting to note that HI test had higher diagnostic specificity and exhibited a stronger positive correlation with SN test than IFA test. Evaluating the performance of HI and IFA tests with experimental and field serum samples revealed that both tests showed comparable performance with SN test in terms of antibody kinetic and detection rate. Collectively, these findings support the use of both tests, particularly HI test, as the alternative to SN test for measuring the antibody responses against DTMUV in ducks. These tests could be the suitable choices for DTMUV diagnosis, epidemiological study and vaccine efficacy evaluation. [ABSTRACT FROM AUTHOR]

To improve cross-protection of influenza vaccination, we tested conjugation of conserved M2e epitopes to the surface of inactivated influenza virus (iPR8-M2e*). Treatment of virus with chemical cross-linker led to diminished hemagglutination activity and failure to induce hemagglutination inhibiting antibodies. Conjugated iPR8-M2e* vaccine was less protective against homologous and heterosubtypic viruses, despite the induction of virus-specific binding IgG antibodies. In alternative approaches to enhance cross-protection, we developed a genetically linked chimeric protein (M2e-B stalk) vaccine with M2e of influenza A and hemagglutinin (HA) stalk of influenza B virus. Vaccination of mice with inactivated influenza A virus supplemented with M2e-B stalk effectively induced hemagglutination inhibiting antibodies, humoral and cellular M2e immune responses, and enhanced heterosubtypic protection. This study demonstrates the importance of HA functional integrity in influenza vaccine efficacy and that supplementation of influenza vaccines with M2e-B stalk protein could be a feasible strategy of improving cross-protection against influenza viruses. • Chemical modification of inactivated influenza virus can lead to a loss of hemagglutination activity. • HA functional integrity in influenza vaccines is critical for inducing protective antibodies and homo and hetero protection. • Supplementing M2e immunity to influenza vaccination provides a feasible strategy for enhancing cross protection. [ABSTRACT FROM AUTHOR]

Novel high-performance biosensing devices, based on a microporous cellulose matrix, have been of great interest due to their high sensitivity, low cost, and simple operation. Herein, we report on the design and testing of portable paper-based immunostrips (IMS) for in-field blood typing in emergencies requiring blood transfusion. Cellulose fibrils of a paper membrane were functionalized with antibodies via supramolecular interactions. The formation of hydrogen bonds between IgM pentamer and cellulose fibers was corroborated using quantum mechanical calculations with a model cellulose chain and a representative amino acid sequence. In the proposed immunostrips, paper with a pore size of 3 µm dia. was used to enable functionalization of its channels with antibody molecules while blocking the red blood cells (RBC) from channel entering. Under the optimized test conditions, all blood types of AB0 and Rh system could be determined by naked eye examination, requiring only a small blood sample (3.5 µL). The durability of IgM immunostrips against storing has been tested. A new method of statistical evaluation of digitized blood agglutination images, compatible with a clinical five-level system, has been proposed. Critical parameters of the agglutination process have been established to enable future development of automatic blood typing with machine vision and digital data processing. [ABSTRACT FROM AUTHOR]

In Japan, inactivated influenza vaccines are used. We measured titers of antibodies to vaccine strains of three influenza types—influenza A (H1N1), influenza A (H3N2), and influenza B/Victoria—from the 2017/2018 to 2021/2022 seasons, but not for influenza A (H3N2) from the 2018/2019 season, using a single set of serum samples from 34 healthy volunteers, and assessed the consistency in antibody positivity between seasons. The antibody titers in the 2017/2018 season were used as a reference. The influenza A (H1N1) antibody titer in 2019/2020 did not differ significantly from that in the 2017/2018 season, but the titers varied in the two subsequent seasons. The influenza A (H3N2) antibody titers toward the 2019/2020, 2020/2021, and 2021/2022 seasonal viruses differed significantly from that in the 2017/2018 season. The influenza B/Victoria antibody titer toward the 2019/2020 seasonal antigen differed from that in the 2017/2018 season, and the antibody positivity was inconsistent between seasons; however, the antibody titer in the 2020/2021 season did not differ significantly from those in the prior two seasons, and the antibody positivity was consistent between seasons. Antibody titers and their consistency can be used to evaluate cross-immunity of antibodies. [ABSTRACT FROM AUTHOR]

Agglutinins/lectins are conventionally defined as proteins/ glycoproteins of non-immune origin with a remarkable ability to specifically and reversibly interact with carbohydrate ligands. Lectins from different sources may essentially exhibit common biological activities. This study was therefore undertaken to survey naturally occurring agglutinins in two species of marine crabs by hemagglutination assay using mammalian erythrocytes. Hemagglutination assay results showed that the hemolymph of the marine crab Grapsus albolineatus showed the highest HA titer with rat erythrocytes. HA titer of the crab Leptodius sanguineus varied from 0 to 32 with all the tested erythrocytes. Among the various tissues of Grapsus albolineatus analyzed for the presence of agglutinins, hemagglutination activity was observed in the hemolymph and hepatopancreas with rat erythrocytes. HA was determined by both male and female crabs of Grapsus albolineatus. HA activity increased with an increase in animal size. Biochemical factors like water, protein and calcium content of the hemolymph did not have any influence on the HA titer. [ABSTRACT FROM AUTHOR]

Russell's viper being one of the most venomous snake species in Asia causes significant amount of snake bites and deaths due to neurotoxicity, coagulopathy, haemorrhage, cardiotoxicity, myotoxicity, hypotension, oedema, tissue damage and convulsion. Treatment with monoclonal antibodies, anti-snake venom is the only medically approved treatment available for snake envenomation and has many limitations and side effects such as anaphylactic shock, skin rashes, nausea to vomiting and fever, chills, hypotension, seizures, serum sickness, pruritus, urticaria, arthralgia, lymphadenopathy, encephalopathy etc. Recently, nanoscience and nanotechnology are playing an important role in medical field and has proven to be quite beneficial. In present study, chemically synthesized silver nanoparticles (40±3 nm) are used to inhibit Russell's viper venom activity. The silver nanoparticles and albumin conjugated with curcumin was prepared and characterized using spectroscopic techniques. Venom inhibitory potency of the prepared conjugate was analysed using acidimetry, protease assay and whole blood clotting test. The ultravioletvisible spectra showed enhancement in absorbance of venom with significant hyperchromic shift and thus confirmed modification of venom by silver nanoparticles. This also led to the enhanced interaction with bovine serum albumin-curcumin conjugates. Fluorescence data also showed strong interaction between the conjugates and venom. Interestingly the activity of Russell's viper venom was reduced to 75 %-96 %. The possible mechanism of action of bovine serum albumin-curcumin complex on venom treated with silver nanoparticles is explained at molecular level and biocompatibility of the same was also analysed. Blood agglutination by bovine serum albumin-curcumin complex showed its in vitro biocompatibility. [ABSTRACT FROM AUTHOR]

In the current study, the roots of Quercus agrifolia Nee were subjected to phytochemical analysis to determine the presence of various compound groups. To explore the effect of Quercus agrifolia Nee roots, we evaluated four solvent extracts, namely, crude ethanolic extract (CEE), n-hexane, chloroform (CHCl3), and ethyl acetate (EtOAc), for their antibacterial, antifungal, and hemagglutination activities. Agar well diffusion and agar tube dilution methods were used to determine the antibacterial and antifungal effects, respectively, and hemagglutination activity was measured against human erythrocyte blood groups. The qualitative phytochemical analysis of the solvent extracts of Quercus agrifolia Nee roots showed the presence of different classes of compounds, i.e., flavonoids, coumarins, terpenoids, etc. The CEE and various fractions were tested against Escherichia coli, Listeria monocytogenes, Alcaligenes faecalis, and Pseudomonas aeruginosa, with CEE exhibiting the widest zone of inhibition against A. faecalis (30 mm) and moderate activities against P. aeruginosa (18 mm%), L. monocytogenes (18 mm%), and E. coli (20 mm%). The n-hexane fraction and the remaining fractions had moderate to good activity against all the four bacterial strains. The antifungal ability of plant roots was also tested against four separate fungal strains, i.e., Alternaria solani, Aspergillus niger, Triticum harzianum, and Fusarium oxysporium, and the n-hexane extract showed a higher activity than the CEE. During the investigation by hemagglutination assay, some solvent extracts exhibited a low amount of lectin complex in the selected plant. The current study revealed that the roots of Quercus agrifolia Nee has an ideal medicinal viability and contains a diverse range of phytochemical classes. This research is the first systematic study of Quercus agrifolia Nee roots, demonstrating its versatility in a variety of biological activities. [ABSTRACT FROM AUTHOR]

Typhoid fever poses a serious public health problem in Nigeria and is largely diagnosed based on the Widal agglutination test which has been proven to be neither sensitive nor specific. This study determined the prevalence of typhoid fever using both Widal agglutination test and blood culture using automated microbiology systems (BD BACTEC). The study was carried out among 90 patients attending Murtala Muhammad Specialist Hospital in Kano. Out of the 90 cases recruited for the study, none of the cases (0, 0.0%) had S. Typhi isolated using blood culture. However, 18 cases (20%) had other bacteria which are not S. Typhi isolated using blood culture while 72 cases (80%) were negative. For the Widal test, 63 cases (70%) were positive for anti S. Typhi O antigen while 27 cases (30%) were negative. Similarly, 42 cases (46.7%) were positive for anti S. Typhi H antigen, while 48 cases (53.3%) were negative. Type of toilet system was found to be significantly associated with non S. Typhi bacteraemia (P=0.021). The study recommends the use of other diagnostic test such as molecular techniques to determine the sensitivity and specificity of both Widal and cultural methods. [ABSTRACT FROM AUTHOR]

Proteasomes are major non‐lysosomal proteolytic complexes localized in the cytoplasm and in the nucleus of eukaryotic cells. Strikingly, high levels of extracellular proteasome have also been evidenced in the plasma (p‐proteasome) of patients with specific diseases. Here, we examined the process by which proteasomes are secreted, as well as their structural and functional features once in the extracellular space. We demonstrate that assembled 20S core particles are secreted by cells within microvesicles budding from the plasma membrane. Part of the extracellular proteasome pool is also free of membranes in the supernatant of cultured cells, and likely originates from microvesicles leakage. We further demonstrate that this free proteasome released by cells (cc‐proteasome for cell culture proteasome) possesses latent proteolytic activity and can degrade various extracellular proteins. Both standard (no immune‐subunits) and intermediate (containing some immune‐subunits) forms of 20S are observed. Moreover, we show that galectin‐3, which displays a highly disordered N‐terminal region, is efficiently cleaved by purified cc‐proteasome, without SDS activation, likely after its binding to PSMA3 (α7) subunit through its intrinsically disordered region. As a consequence, galectin‐3 is unable to induce red blood cells agglutination when preincubated with cc‐proteasome. These results highlight potential novel physio‐ and pathologic functions for the extracellular proteasome. [ABSTRACT FROM AUTHOR]

This study demonstrated the terminated sialo‐sugar chains (Neu5Acα2,6Gal and Neu5Acα2,3Gal)‐mediated specificity enhancement of influenza virus and chicken red blood cell (RBC) by hemagglutination assay. These glycan chains were immobilized on the gold nanoparticle (GNP) to withhold the higher numbers. With the preliminary optimization, a clear button formation with 0.5% RBC was visualized. On the other hand, intact B/Tokio/53/99 with 750 nM hemagglutinin (HA) displayed a nice hemagglutination. The interference on the specificity of RBC and influenza virus was observed by anti‐influenza aptamer at the concentration 31 nM; however, there is no hemagglutination prevention was noticed in the presence of complementary aptamer sequences. Spiking GNP‐conjugated Neu5Acα2,6Gal or Neu5Acα2,3Gal or a mixture of these two to the reaction promoted the hemagglutination to 63‐folds higher with 12 nM virus, whereas under the same condition the heat‐inactivated viruses were lost the hemagglutination. Neuraminidases from Clostridium perfringens and Arthrobacter ureafaciens at 0.0025 neuraminidase units are able to abolish the hemagglutination. Other enzymes, Glycopeptidase F (Elizabethkingia meningoseptica) and Endoglycosidase H (Streptomyces plicatus) did not show the changes with agglutination. Obviously, sialyl‐Gal‐terminated glycan‐conjugated GNP amendment has enhanced the specificity of erythrocyte–influenza virus and able to be controlled by aptamer or neuraminidases. [ABSTRACT FROM AUTHOR]

Avian influenza virus (AIV) H7N9 diseases have been recently reported, raising concerns about a potential pandemic. Thus, there is an urgent need for effective therapeutics for AIV H7N9 infections. Herein, camelid immunization and yeast two-hybrid techniques were used to identify potent neutralizing nanobodies (Nbs) targeting the H7 subtype hemagglutinin. First, we evaluated the binding specificity and hemagglutination inhibition activity of the screened Nbs against the H7 subtype hemagglutinin. Nb-Z77, with high hemagglutination inhibition activity was selected from the screened Nbs to optimize the yeast expression conditions and construct oligomeric forms of Nb-Z77 using various ligation methods. The oligomers Nb-Z77-Di GS , Nb-Z77-Tri GS , Nb-Z77-Fc and Nb-Z77-Foldon were successfully constructed and expressed. Nb-Z77-Di GS and Nb-Z77-Foldon exhibited considerably greater activity than did Nb-Z77 against H7 subtype hemagglutinin, with median effective concentrations of 384.7 and 27.33 pM and binding affinity values of 213 and 5.21 pM, respectively. Nb-Z77-Di GS and Nb-Z77-Foldon completely inhibited the hemagglutination activity of the inactivated virus H7-Re1 at the lowest concentration of 0.938 μg/mL. This study screened a strain of Nb with high hemagglutination inhibition activity and enhanced its antiviral activity through oligomerization, which may have great potential for developing effective agents for the prevention, diagnosis, and treatment of AIV H7 subtype infection. • A nanobody strain against the AIV H7 subtype was screened using a yeast two-hybrid assay. • The yeast expression conditions for the recombinant nanobody were optimized. • The oligomers showed greater neutralizing activities than did the monomeric nanobody. [ABSTRACT FROM AUTHOR]

Canine adenoviruses (CAdVs) include type 1 (CAdV-1, virulent strain) and type 2 (CAdV-2, attenuated strain). In recent years, the incidences of CAdV infections are increasing. However, they are difficult to distinguish when the symptoms are untypical. It is pivotal to find the differences between the two virus types for scientific, epidemiological, and specific treatment. CAdV-1 (virulent strain) and CAdV-2 (attenuated strain) induced canine hepatitis (ICH) and tracheobronchitis (ITB), respectively, but the clinical symptom is not obvious. CAdV-1 and CAdV-2 have the same genome structure, diameter, morphological features, and cytopathic features, but the same character hinder the diagnose time of the serotypes. CAdV-1 and CAdV-2 have a difference in the genome sequence, coding proteins, viral activity, hemagglutination patterns. After infection, pathogenicity and transmission route are different between the two serotypes. Sequence alignment, PCR, Real time-PCR assay are useful methods to distinguish the two serotypes. The attenuated live CAdV-2 vaccine is currently used to protect against CAdV-1, but it also has a risk. The further research should focus on the pathogenicity mechanism and the useful vaccine for the two serotypes of canine adenovirus. [ABSTRACT FROM AUTHOR]

Olea ferruginea has been used to treat skin ailments, as well as kidney and ocular problems for a long time. The current study was designed with the aim of investigating and scientifically validating its widespread use. Chloroform, n-hexane, and ethyl acetate were used to assess the antibacterial, hemagglutination, and insecticidal properties of O. ferruginea roots. Escherichia coli, Micrococcus luteus, Klebsiella pneumoniae, and Pseudomonas aeruginosa were among the bacterial strains selected for assessing antibacterial activity. The results showed that ethyl-acetate (EtOAc) extract (56%) and chloroform (CHCl3) extract (56%) showed the widest zone of inhibition against K. pneumonia, while n-hexane extract (13.4%) had the lowest zone of inhibition against P. aeruginosa. All three extracts remained inactive against M. luteus. During hemagglutination activity, the CHCl3 and EtOAc extracts, when used at different concentrations, only agglutinated the AB-ve and O+ve blood groups, respectively, while the n-hexane extract strongly agglutinated the A-ve and B-ve blood groups at different concentrations. The plant extracts were also checked for insecticidal activity against Rhizopertha dominica. The results also revealed the high mortality rate of CHCl3 extract (70%) against R. dominica as compared to other extracts. The aforesaid activities suggest that the roots of O. ferruginea have excellent medicinal viability and contain a wide variety of agglutinins and lectins, as shown in this study. [ABSTRACT FROM AUTHOR]

Rabies vaccine preparations are quantitatively assayed for potency using the in-vivo challenge National Institute of Health (NIH), the main test that consumes a high number of animals, takes a long time, and has wide variability. The Rapid focus fluorescent inhibition (RFFIT) and the passive hemagglutination (PHA) tests, the two serologically based tests, were also used for such purpose. In this study, we aimed to evaluate and correlate the potency of the NIH, RFFIT, and PHA tests according to the World Health Organization (WHO) validity criteria, aiming to validate the use of RFFIT or PHA test as a substitute to the NIH test for determining the potency of commercially available Rabies vaccine preparations. The results showed that, the three tests can be successfully used; however, a higher correlation between RFFIT and NIH than PHA and NIH was recorded (Pearson correlation = 1). The potency of rabies vaccine preparations using NIH, RFFIT, and PHA were 3.73, 3.51, and 4.50, respectively. NIH is the main test for the determination of vaccine potency carried out by conducting 25 experiments and consuming about 5,000 mice compared to 1,200 mice used with RFFIT and 1,000 mice used with PHA test. Taken together, we concluded that (i) in some tested preparations, both RFFIT and PHA tests gave comparable results, and they can be used interchangeably; (ii) RFFIT could successfully replace NIH test, but not PHA; (iii) RFFIT and PHA tests are faster, more accurate, more economic, and more sensitive than NIH; nevertheless, PHA needs further investigations; and (iv) both RFFIT and NIH tests complement and reinforce each other as they provide a comprehensive picture of the product potency. [ABSTRACT FROM AUTHOR]

Influenza still represents a problematic disease, involving millions of people every year and causing hundreds of thousands of deaths. Only a few drugs are clinically available. The search for an effective weapon is still ongoing. In this scenario, we recently identified new drug-like compounds with antiviral activity toward two A/H1N1 Influenza virus strains, which were demonstrated to interfere with the processes mediated by hemagglutinin (HA). In the present work, the compound's ability to act against the A/H3N2 viral strain has been evaluated in hemagglutination inhibition (HI) assays. Two of the five tested compounds were also active toward the A/H3N2 Influenza virus. To validate the scaffold activity, analogue compounds of two broad-spectrum molecules were selected and purchased for HI testing on both A/H1N1 and A/H3N2 Influenza viruses. Forty-three compounds were tested, and four proved to be active toward all three viral strains. A computational study has been carried out to depict the HA binding process of the most interesting compounds. [ABSTRACT FROM AUTHOR]

Background: The annual death associated with seasonal influenza is 290,000–650,000 globally, which can be effectively reduced by influenza vaccination. However, the protective hemagglutination inhibition (HAI) antibody response to influenza vaccine is affected by many factors, among which single nucleotide polymorphisms (SNPs) in the human leukocyte antigen (HLA) region can alter the antigen-presenting function of the HLA molecule, thus influencing the process of antibody mounting against vaccine antigen. Methods: Healthy subjects of the Han nationality were recruited and received seasonal trivalent influenza vaccine. Paired serum samples collected on and approximately 28 days after vaccination were tested in parallel by HAI assays. HLA alleles related to the immune response to influenza vaccine reported in the previous literature were summarized, and six corresponding tag SNPs were selected and genotyped using the MassARRAY technology platform. Results: The effects of HLA SNPs on HAI antibody response to influenza vaccine varied with different vaccine antigens. The AA genotype of rs41547618 was correlated with low A/H1N1-specific antibody titer compared with the GG + GA genotype (p =.007). The TT genotype of rs17885382 was correlated with low A/H3N2-specific antibody titer compared with the CC + CT genotype (p =.003). In addition, haplotype consisting of rs41542812—rs17885382—rs2068205—rs41547618—rs6905837—rs9270299—CCTGCA was correlated with non-responsiveness to influenza vaccine (OR = 2.39, 95% CI = 1.02–5.62). Conclusion: HLA SNPs were associated with HAI antibody response to influenza vaccine, which can help in a better understanding of the varied responsiveness to influenza vaccine in the population. [ABSTRACT FROM AUTHOR]

Background Data from a randomized controlled efficacy trial of an inactivated quadrivalent influenza vaccine in children 6–35 months of age were used to determine whether hemagglutination inhibition (HI) antibody titer against A/H1N1 and A/H3N2 is a statistical correlate of protection (CoP) for the risk of reverse-transcription polymerase chain reaction (RT-PCR)–confirmed influenza associated with the corresponding strain. Methods The Prentice criteria were used to statistically validate strain-specific HI antibody titer as a CoP. The probability of protection was identified using the Dunning model corresponding to a prespecified probability of protection at an individual level. The group-level protective threshold was identified using the Siber approach, leading to unbiased predicted vaccine efficacy (VE). A case-cohort subsample was used for this exploratory analysis. Results Prentice criteria confirmed that HI titer is a statistical CoP for RT-PCR–confirmed influenza. The Dunning model predicted a probability of protection of 49.7% against A/H1N1 influenza and 54.7% against A/H3N2 influenza at an HI antibody titer of 1:40 for the corresponding strain. Higher titers of 1:320 were associated with >80% probability of protection. The Siber method predicted VE of 61.0% at a threshold of 1:80 for A/H1N1 and 46.6% at 1:113 for A/H3N2. Conclusions The study validated HI antibody titer as a statistical CoP, by demonstrating that HI titer is correlated with clinical protection against RT-PCR–confirmed influenza associated with the corresponding influenza strain and is predictive of VE in children 6–35 months of age. Clinical Trials Registration NCT01439360. [ABSTRACT FROM AUTHOR]

Objective. To develop a novel sensitive and accurate assay suitable for high-volume testing of the total complement activity in the serum for clinical laboratories. Methods. The total complement activity (TCA) to be measured was quantified by detecting the number of fragments produced by erythrocyte lysis and the erythrocyte fragmentation index (EFI), indicating TCA. EFI = M × M 2 / M 1 + M 2 , where M is the number of erythrocyte fragments (removed from the background), M 1 is the number of unagglutinated red cells, M 2 is the number of agglutinated red cell groups, and M 2 / M 1 + M 2 is the agglutination coefficient indicating the degree of erythrocyte agglutination. Mild changes in hemolysin and erythrocyte concentrations were made to optimize the testing conditions. The same serum samples were tested for 10 consecutive days to determine the stability of the experimental results. Serum EFI was detected in both nephrotic syndrome patients and healthy subjects. Results. There was a linear relationship between hemolysin and erythrocyte agglutination (r = 0.999 , P < 0.001). A good linear relationship existed between EFI and TCA (r = 0.991 , P < 0.001). The results were not affected by slight fluctuations in the concentrations of hemolysin or erythrocytes. The interbatch CV = 8.6 % of the test results showed good stability. There was a significant difference in the EFI between nephrotic syndrome patients and healthy individuals, P < 0.001 , and EFI was reduced in nephrotic syndrome patients compared to healthy individuals. Conclusion. The flow cytometry-based assay for TCA was sensitive and accurate and had potential value for clinical application. [ABSTRACT FROM AUTHOR]