Lo T, Haridas RS, Rudge EJM, et al. - As early as three months after surgery, laparoscopic sleeve gastrectomy (LSG) causes dramatic alterations in the composition and metabolism of immune cells. More research is needed to determine the impact of bariatric surgery on immunometabolism and the implications for host defiance and metabolic disease.

• Prospective data were obtained from 23 human individuals enrolled at a single institution.

• At three months, LSG resulted in a substantial decrease in mean total body weight loss (18.1%) and a decrease in HbA1c in diabetic participants.

• Clinical inflammatory and hormonal biomarker improvements were seen as early as three months after LSG.

• A decrease in the neutrophil-lymphocyte ratio was detected, which was caused by a decrease in absolute neutrophil counts.

• After three months, LSG elicited transcriptomic changes not only in inflammatory cytokine pathways but also in several key metabolic pathways related to energy metabolism, according to gene set enrichment studies of differential whole blood gene expression.