FIGURE 5.

Hormones and COVID19. High E2 and P4 concentrations in females (even higher in pregnancy) helps to suppress proinflammatory cytokine production by macrophages and prevent migration of monocytes and neutrophils into inflamed tissues. CD4 + helper cells are stimulated to produce anti-inflammatory cytokines and T regulatory cells promote immune tolerance. E2 also stimulates production of antibodies. Together, this results in a stronger immune response, faster viral clearance and less severe COVID infection in women. Androgens e.g., T/DHT and AR signaling increases expression of ACE2 and TMPRSS2 promoting viral entry. Together, T/DHT’s immunosuppressive effects, male behavioral factors and co-morbidities can contribute to a more severe COVID infection and worse outcome in males.