Simultaneously, alongside this, markers of exhaustion such as lymphocyte-activation gene 3 (LAG3), T cell immunoglobulin and mucin domain containing protein 3 (TIM-3), programmed cell death protein 1 (PD1), and TIGIT have been identified on NK cells in individuals diagnosed with COVID-19 [118, 119]. The gene discussed is HAVCR2; the disease is COVID-19.