(M0930-02-07) Low Blood Volume Alternative for Monitoring COVID-Specific T-Cell Immunity

Purpose: This submission outlines the development of a novel whole blood-based T-cell immunity testing kit. This kit aims to bring T-cell function testing into mainstream clinical diagnostics and predictive health. Its primary objective is to bridge the gap in measuring T-cell-mediated immunity for emerging therapies and vaccines, including COVID-19 and cancer immunotherapies, which currently rely heavily on antibody tests. The kits can also help monitor cellular-immunity in rare-disease in the context of cell/gene therapies

Methods: The testing procedure involves the collection of blood samples and measurement of T-cell-produced IFN-gamma (a key immune response marker) under antigen-stimulated conditions. The kit was tested on vaccinated or COVID-19-recovered individuals and validated by correlating results with ELISpot assays, considered a gold standard for evaluating T-cell immunity. The study highlighted robust correlations between the whole blood assay and traditional methods.

Results: The kit demonstrated strong correlation (r² = 0.78) between IFN-gamma production in whole blood assays and the frequency of SARS-CoV-2-specific T cells in ELISpot assays. It successfully identified COVID-19-specific T-cell immunity, with higher IFN-gamma levels indicating robust immune responses. This platform is resource-efficient, adaptable for large-scale testing, and capable of evaluating immunity in diverse populations, including immune-compromised and pediatric groups. IFN-gamma levels in unstimulated conditions indicate the background level IFN-g produced by the cells in the blood.

Conclusion: The T-cell immunity testing kit represents a significant advancement in clinical diagnostics, enabling widespread assessment of immunity for infectious diseases and immunotherapy efficacy; simplified, economical testing suitable for resource-limited settings; and future expansions to measure antibody titers and specific T-cell subsets (CD4+ and CD8+).

Correlation of IFN-g release in COVID-19 Whole Blood assay with frequency of SARS-CoV-2 specific T cells by ELISpot.

Scientific Basis and Procedure of Test