Role of T Lymphocyte Activation Profile in Predicting SARS-CoV-2 Severity: Experience from Tertiary Care Centre of North India.

Abstract

BackgroundImmune dysregulation plays a key role in determining COVID-19 disease severity. We aimed to analyze the T cell activation profile in COVID − 19 cases and its predictive role in disease severity and outcome.Material & methodsThis was a prospective observational pilot study from a tertiary care COVID-19 hospital. Peripheral blood samples obtained between the fifth and seventh day of COVID-19 illness, were subjected to lymphocyte subset analysis using multicolor flowcytometry using a single tube, 8 antibodies (CD45, CD19, CD3, CD4, CD8, CD38, HLADR, and CD56) analysis. Correlation between lymphocyte subset analysis and clinical profile was determined.Results26 patients including 11 with mild disease and 15 with severe disease were enrolled. The median age was 58 years (range: 33–81), with a male: female ratio of 1.36:1. Significant lymphopenia was observed in the severe group compared to the mild group (p < 0.02). The absolute numbers of CD3+, CD4+, CD8 + T cells, B cells, and NK cells were significantly reduced in the severe group as compared to the mild group (p < 0.05). In patients with severe disease, the proportion of CD8 + and CD4 + T cells were significantly higher than those in patients with mild disease (p = 0.0372). Using ROC analysis, a CD4:8 T cell ratio of ≥ 2.63 and an activated (CD38 + HLA-DR+) CD8 T cell proportion of > 15.85% of the total CD8 T cell population, significantly determined the severe disease category.ConclusionsSevere COVID-19 is associated with severe lymphopenia, altered CD4/CD8 ratio and markedly increased CD8 T cell activation profile.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12288-022-01558-6.