Cellular Immunity in Obesity: Pathophysiological Insights and the Impact of Bariatric Surgery

Obesity is considered a state of chronic low-grade inflammation that impacts the development of chronic degenerative diseases. Cellular immunity plays a crucial role in the onset and persistence of this inflammatory condition. As the degree of obesity increases, significant distinct immunometabolic alterations are observed compared to individuals with normal weight. Moreover, obese patients who undergo bariatric surgical procedures for weight loss exhibit changes in the proportion of immune cells. These alterations help to explain several molecular processes associated with inflammation in obesity, including protein activation and inactivation, precursor molecule synthesis, phosphorylation events, and the activation of signal transduction pathways, all of which are orchestrated by immune cells, primarily lymphocyte subpopulations. The study of the immunometabolic profile through lymphocyte subpopulations in obese patients can provide a more comprehensive and objective understanding of disease severity and the risk of developing obesity-related chronic degenerative conditions and thereby improve or propose therapeutic and novel approaches. Therefore, the objective of this narrative review is to offer an integrative perspective on the molecular and pathophysiological mechanisms through which lymphocyte populations contribute to obesity-related inflammation and how weight loss through bariatric surgical procedures may contribute to the therapeutic management of inflammation.