Potent SARS‐CoV2‐specific T‐cell response in asymptomatic hemodialysis patients with hidden COVID‐19 infection history

BACKGROUND: COVID‐19‐related immune responses in patients with end‐stage renal disease (ESRD) are characterized in detail by the humoral response, but their cellular immunity has not been clarified. Here, we evaluated virus‐specific T cells in parallel with serology‐related tests. METHODS: In this study, 104 ESRD patients at the hemodialysis ward of Imam Reza hospital at Tabriz (Iran) were enrolled. After blood sampling, SARS‐CoV2‐specific humoral and cellular immune responses were evaluated by SARS‐CoV2‐specific IgM/IgG ELISA and peptide/MHCI‐Tetramers flow cytometry, respectively. RESULTS: Our results showed that 14 (13.5%) and 45 (43.3%) patients had specific SARS‐CoV2 IgM and IgG in their sera, respectively. Immunophenotyping for SARS‐CoV2‐specific CD8(+) T lymphocytes revealed that 68 (65.4%) patients had these types of cells. Among SARS‐CoV2‐specific CD8(+) T lymphocytes positive subjects, 13 and 43 individuals had positive results for specific SARS‐CoV2 IgM and IgG existence, respectively. Also, there was a relationship between specific SARS‐CoV2 IgM (p = 0.031) and IgG (p < 0.0001) existence and having SARS‐CoV2‐specific TCD8(+) lymphocytes in the studied population. CONCLUSION: Despite not having clinical symptoms, a high rate of SARS‐CoV2‐specific T‐cell response in asymptomatic ESRD patients may reveal a high burden of asymptomatic COVID‐19 infection in these patients.