CD4 and COVID-19: We have established a more significant increase in the level of IL-1β in patients with OA in the post-COVID-19 period, comparing to patients in the absence of viral lesions, as well as other pro-inflammatory cytokines (32), associated with T cells, may be related with increased activation and proliferation of SARS-CoV-2 specific CD4 and CD8 T cell clonotypes, as well as reduction of NK cells, that is characteristic of convalescents for a long period of time after the disappearance of the infection (33).