Cost effective and reliable cell based ELISA as an alternative method of flow cytometry for assessment of binding activity of Vedolizumab.

Vedolizumab is a humanized monoclonal antibody used for inflammatory bowel disease treatment. Vedolizumab binds to the α4ß7 integrin complex and inhibits its binding to mucosal addressin cell adhesion molecule-1 (MAdCAM-1). To evaluate the binding efficacy and quality control check of Vedolizumab, flow cytometry is performed by using HuT78 cells. As we know, flow cytometer is costly and require high equipment maintenance with a designated technical manpower to handle it. In this regard, the aim of study was to develop and validate an economical, simple and efficient cell based ELISA assay for potency estimation of Vedolizumab which has not been reported in any pharmacopoeia. The proposed bioassay method was optimized by investigating Vedolizumab binding to α4ß7 integrin which is expressed by HuT78 cells. The validation of this method was done at different parameters including specificity, linearity, range, repeatability, precision, and accuracy. The Vedolizumab binding by ELISA results were found specific for Vedolizumab with linearity (R2 = 0.99) and precision (%Geometric Coefficient of variance) observed for repeatability and intermediate precision were 3.38% and 2.6% respectively. The relative bias was calculated as 8.68% for repeated performances by different analysts and found in accordance with parameter of accuracy as per various pharmacopoeial guidelines. The developed method is established as robust, effective, and less expensive than high maintenance setup like flow cytometry based assay.

In-vitro carbofuran induced genotoxicity in human lymphocytes and its mitigation by vitamins C and E.

Various efforts have been made in past in order to predict the underlying mechanism of pesticide-induced toxicity using in vitro and animal models, however, these predictions may or may not be directly correlated with humans. The present study was designed to investigate the carbofuran induced genotoxicity and its amelioration by vitamins C and E by treating human peripheral blood lymphocytes (PBLs) with different concentrations (0, 0.5, 1.25, 2.5, 3.75 and 5.0 µM) of this compound. The treatment of PBLs with carbofuran displayed significant DNA damage in concentration dependent manner. The carbofuran induced genotoxicity could be ameliorated to considerable extent by pretreatment of PBLs with equimolar (10 µM) concentration of each of the vitamins C and E; the magnitude of protection by vitamin E being higher than by vitamin C. Also, it was found that the level of protection by these vitamins was higher when PBLs were treated with lower concentrations of pesticide. The significant DNA damage as observed by H_{2}O_{2}, a positive control in the present study, and its amelioration by natural antioxidants (vitamins C and E) lend an evidence to suggest that carbofuran would have caused genotoxicity via pesticide induced oxidative stress.