IL17A and COVID-19: In addition, some authors noted the accumulation of unconventional Th1 cells expressing CD161 and interleukin-1 receptor type I (IL-1RI) markers, which are more typical of Th17 cells, in the peripheral blood of COVID-19 patients with pneumonia, but unlike Th17 cells, these unconventional Th1 cells do not produce IL-17 [89].