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Savargaonkar, D.

Publications and source records attributed to Savargaonkar, D..

2 recordsLinked to original sources

Genotyping of paired clinical isolates using PvCSP, PvMSP3α PvMSP3βand exploring STRs to differentiate between relapse and reinfection in P. vivax

The challenge of eliminating Vivax malaria is due to the relapses caused by hypnozoites. Despite several attempts to identify molecular markers to differentiate between relapse and new infection, a reliable marker has not yet been established. To address this issue, a genomic study was conducted on paired samples of patients who had experienced Plasmodium vivax infection twice. Genotyping was performed on paired samples from 10 vivax malaria patients using five molecular markers to distinguish between relapse and new infection. Our findings indicate that one sample represented a second episode that was a relapse of the first, while another sample had three episodes, two of which were relapse episodes. We combined our clinical records with molecular inferences to identify each pair as a relapse. This particular study provides a momentary view of forthcoming research endeavors that could be undertaken to distinguish between a relapse and a novel infection. Given the notable genetic variability of Plasmodium vivax, it is crucial to harness various markers to discern between relapse and new infection. The findings of this study are poised to be of immense utility for upcoming marker research in the aforesaid aspect.

genomics↗

Characterization of neutralizing versus binding antibodies and memory B cells in COVID-19 recovered individuals from India

India is one of the countries most affected by the recent COVID-19 pandemic. Characterization of humoral responses to SARS-CoV-2 infection, including immunoglobulin isotype usage, neutralizing activity and memory B cell generation, is necessary to provide critical insights on the formation of immune memory in Indian subjects. In this study, we evaluated SARS-CoV-2 receptor-binding domain (RBD)-specific IgG, IgM, and IgA antibody responses, neutralization of live virus, and RBD-specific memory B cell responses in pre-pandemic healthy versus convalescent COVID-19 individuals from India. We observed substantial heterogeneity in the formation of humoral and B cell memory post COVID-19 recovery. While a vast majority (38/42, 90.47%) of COVID-19 recovered individuals developed SARS-CoV-2 RBD-specific IgG responses, only half of them had appreciable neutralizing antibody titers. RBD-specific IgG titers correlated with these neutralizing antibody titers as well as with RBD-specific memory B cell frequencies. In contrast, IgG titers measured against SARS-CoV-2 whole virus preparation, which includes responses to additional viral proteins besides RBD, did not show robust correlation. Our results suggest that assessing RBD-specific IgG titers can serve as a surrogate assay to determine the neutralizing antibody response. These observations have timely implications for identifying potential plasma therapy donors based on RBD-specific IgG in resource-limited settings where routine performance of neutralization assays remains a challenge. ImportanceOur study provides an understanding of SARS-CoV-2-specific neutralizing antibodies, binding antibodies and memory B cells in COVID-19 convalescent subjects from India. Our study highlights that PCR-confirmed convalescent COVID-19 individuals develop SARS-CoV-2 RBD-specific IgG antibodies, which correlate strongly with their neutralizing antibody titers. RBD-specific IgG titers, thus, can serve as a valuable surrogate measurement for neutralizing antibody responses. These finding have timely significance for selection of appropriate individuals as donors for plasma intervention strategies, as well as determining vaccine efficacy.

immunology↗