The phenotypic changes of γδ T cells in COVID‐19 patients

A novel pneumonia‐associated respiratory syndrome named coronavirus disease‐2019 (COVID‐19), which was caused by SARS‐CoV‐2，broke out in Wuhan, China, in the end of 2019. Unfortunately, there is no specific antiviral agent or vaccine available to treat SARS‐CoV‐2 infections. The information regarding the immunological characteristics in COVID‐19 patients remains limited. Here, we collected the blood samples from 18 healthy donors (HD) and 38 COVID‐19 patients to analyze changes on γδ T cell population. In comparison with HD, the γδ T cell percentage decreased, while the activation marker CD25 expression increased in response to SARS‐CoV‐2 infection. Interestingly, the CD4 expression was upregulated in γδ T cells reflecting the occurrence of a specific effector cell population, which may serve as a biomarker for the assessment of SARS‐CoV‐2 infection.