FABP4 and infection: It is worth noting that, aside from adipocytes, endothelial cells and macrophages are two major sources of FABP4 (Prentice et al, 2019) and while neither cell type supports SARS-CoV-2 replication, their infection leads to increased proinflammatory cytokine production (Martínez-Colón et al, 2022; Wagner et al, 2021).