TGFB1 and COVID-19: Strikingly, myeloid-derived suppressor cells (MDSC) from COVID-19 patients suppress T effector cells but this effect can be blocked with a neutralizing antibody to TGF-β, and this TGF-β antibody also rescued interferon responses in MDSC to SARS-CoV-2 antigens, where the number of MDSC also correlated with plasma TGF-β1 levels (83).