Figure 1.

The figure shows the immunosuppression in obese subjects. The adipose tissue of the obese is highly inflamed and, consequently, releases a number of cytokines, particularly IL-6 and TNF-α. whose secretion is further potentiated by leptin. The lipopolysaccharide (LPS)-triggered endotoxemia further aggravates inflammatory condition by inducing the release of IL-6 and TNF-α from macrophages via TLR4 activation. Obesity is also marked with high production of IL-10, which decreases the function of dendritic cells. The prolonged inflammation will lead to immunosuppression that may favor the viral infection. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has also been shown to induce immunosuppression. Once installed, SARS-CoV-2 will aggravate the obesity-induced lung dysfunctions. (+) and (−) show, respectively, stimulatory and inhibitory actions.