Novel Designs of Cytotoxic T Cell Assays for Point-of-Care and Laboratory measurements of related Host specific Adaptive Responses to Pathogens and Vaccines

Abstract Background The rapid evolution of the global COVID19 pandemic motivated a fast-tracked emergency authorization of vaccines. Majority studies of the efficacy of COVID19 vaccines have only utilized host-specific B cell (antibody) immune responses as the surrogate marker. This, because existing assays for cytotoxic T lymphocyte (CTL) responses are costly, complex and rigorous to standardize and perform. The commonest T cell assays (ELISPOT) focuses on quantifying T cell specific responses (mediated via cytokine and interferon mediators) to the target pathogen. Hypothetically, however, the elementary outcome and thereby functional surrogate biomarker of a desirable effective host T cell response, should be the clonal expansion of pathogen specific T cytotoxic cells. This study aims to describe the design of novel Cytotoxic T cell assays for point-of-care (POC) and laboratory measurements of host specific CTL responses to pathogens and vaccines. Methods Theoretical modelling and design Results Using severe acute respiratory syndrome type II (SARS-CoV2), two design-models of novel for the qualitative and quantitative measurement of host specific cytotoxic T cell responses to the same are presented: (a) a microfluidic lateral flow immunochromatography test (LFT) qualitative assay, and (ii) a quantitative enzyme immono-adsorbent assay (ELISA). Conclusion Qualitative and quantitative assay of host-specific T cytotoxic cells to a pathogen using these novel assays offers us affordable, simple and easy to use POC and laboratory alternatives for assessing the natural or vaccine induced T cytotoxic cell competency to fight off pathogens.