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Effective vaccines against Salmonella Typhi, targeting the Vi capsular polysaccharide, have been developed and are being introduced into routine immunization in endemic countries. Vi conjugated vaccines are also being tested in new multi-component vaccine formulations. Simple, high-throughput and cost-effective assays to quantify Vi-specific IgG in clinical sera are needed. In this study we present the development and qualification of a new anti-Vi ELISA with continuous readout, which expresses results as ELISA Unit/mL (EU/mL). We have qualified the assay in terms of precision, linearity and specificity, demonstrating performance in line with a commercially available anti-Vi ELISA. We have also calibrated the assay against the 16/138 anti-Vi international standard and established conversion factor between EU/mL and international units/mL, to allow comparability of results across studies. In summary, this newassaymet all the suitability criteria and is being used to evaluate anti-Vi responses in clinical studies. [ABSTRACT FROM AUTHOR]

Effective vaccines against Salmonella Typhi, targeting the Vi capsular polysaccharide, have been developed and are being introduced into routine immunization in endemic countries. Vi conjugated vaccines are also being tested in new multi-component vaccine formulations. Simple, high-throughput and cost-effective assays to quantify Vi-specific IgG in clinical sera are needed. In this study we present the development and qualification of a new anti-Vi ELISA with continuous readout, which expresses results as ELISA Unit/mL (EU/mL). We have qualified the assay in terms of precision, linearity and specificity, demonstrating performance in line with a commercially available anti-Vi ELISA. We have also calibrated the assay against the 16/138 anti-Vi international standard and established conversion factor between EU/mL and international units/mL, to allow comparability of results across studies. In summary, this new assay met all the suitability criteria and is being used to evaluate anti-Vi responses in clinical studies.

BACKGROUND All β-agonists are banned as feed additives for growth promotion in animals due to toxic effects on humans after consuming the β-agonist contaminated meats. Phenylethanolamine A ( PA) is a newly emerged β-agonist. Thus there is a need to develop highly sensitive and specific analytical methods for the detection of PA in food samples. In this study, the monoclonal antibody ( mAb) against PA was produced by hybridoma technology and used for the development of enzyme-linked immunosorbent assay ( ELISA). RESULTS The IC50 values and limits of detection ( LODs) of the ELISA using homogeneous combination of coating antigen/antibody for PA were 0.16 ng mL−1 and 0.011 ng mL−1, respectively. The cross-reactive ( CR) values of the assay with 14 structurally related β-agonists were lower than 0.59%. Swine liver and meat samples were spiked with PA at different content and analysed by ELISA. Acceptable recovery rates of 91.40-105.51% and intra-assay coefficients of variation of 1.56-9.92% ( n = 3) were obtained. The ELISA for seven spiked samples was confirmed by LC-MS/ MS with a high correlation coefficient of 0.9881. CONCLUSION The proposed mAb-based ELISA was highly sensitive and specific for PA and could be used as a quantitative/screening method for PA analysis in food samples. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Background: Rotavirus infects almost all children by the age of five. More than 150,000 annual deaths due to rota virus, occurs in India. Aims: This study aimed to determine the incidence of Rotavirus infection in children and compare enzyme - linked immunosorbent assay (ELISA) and a modified polyacrylamide gel elctrophoretic (PAGE) analysis in detection of rota virus in stool samples. Materials and Methods: In this prospective study, a total of 200 stool samples were examined for the presence of Rota virus by ELISA and by a modified PAGE analysis of viral genome. Stool culture was done for common enteric pathogens. Results: Maximum incidence of rotavirus infection was seen in age group of 6m-24 m(32.3%). Excellent correlation of ELISA and PAGE results was found in194 of 200 (97%) specimens. A total of 51 (25.5%) of them were found to be positive for rotavirus by either methods. The proportion of ELISA +ve PAGE –ve samples 1/200 was lower than the proportion of ELISA-ve PAGE +ve samples (5/200). All 51 rotavirus positive cases did not show infection with bacterial pathogens. Conclusion: The modified PAGE technique for the detection of viral RNA was found to be rapid, simple, reliable and less expensive technique.

Abstract: Recurrent depressive disorder (rDD) is a multifactorial disease. Vascular endothelial growth factor (VEGF) is one of the factors that have been suggested to play a role in the etiology and/or development of this disease. Limited information related to the role of VEGFA gene polymorphism in depressive disorder is available. The aim of the study was to analyze the association between VEGFA gene polymorphisms (+405G/C; rs2010963, +936C/T; rs 3025039), VEGFA gene expression, and its serum protein levels in rDD in the Caucasian population. In the current study, 268 patients and 200 healthy controls of the Caucasian origin were involved. Genotyping and gene expression were performed using polymerase chain reaction (PCR)-based methods. Enzyme-linked immunosorbent assay (ELISA) was used for detection of circulating serum VEGF levels. The distribution of VEGFA polymorphism +405G/C differed significantly between rDD patients and healthy subjects. The results of this study indicated that the C allele and CC genotype of VEGFA are risk factors for rDD. Haplotypes CC and TG are the important factors for depression development. Further, VEGFA mRNA expression and VEGF levels were higher in rDD patients than in controls. The VEGFA gene polymorphism may serve as a prognostic factor for rDD development. Our study showed higher levels of both VEGFA mRNA in the peripheral blood cells and serum VEGF in patients diagnosed with rDD than in healthy controls. The obtained results suggest VEGF and the gene encoding the molecule play a role in the etiology of the disease and should be further investigated. [Copyright &y& Elsevier]