Differential cellular and humoral immune responses in immunocompromised individuals following multiple SARS-CoV-2 vaccinations.

Introduction: The heterogeneity of the immunocompromised population means some individuals may exhibit variable, weak or reduced vaccine-induced immune responses, leaving them poorly protected from COVID-19 disease despite receiving multiple SARS-CoV-2 vaccinations. There is conflicting data on the immunogenicity elicited by multiple vaccinations in immunocompromised groups. The aim of this study was to measure both humoral and cellular vaccine-induced immunity in several immunocompromised cohorts and to compare them to immunocompetent controls.

Longitudinal T Cell Responses against Ancestral, Delta, and Omicron SARS-CoV-2 Variants Determined by Rapid Cytokine Release Assay in Whole Blood.

T cell immunity to natural SARS-CoV-2 infection may be more robust and longer lived than Ab responses. Accurate assessment of T cell responses is critical for understanding the magnitude and longevity of immunity across patient cohorts, and against emerging variants. By establishing a simple, accurate, and rapid whole blood test, natural and vaccine-induced SARS-CoV-2 immunity was determined.