Immunonutritional diet modulates natural killer cell activation and Th17 cell distribution in patients with gastric and esophageal cancer

Abstract Objective Although randomized clinical trials have shown that immunonutrition results in the improvement of postoperative complications, the detailed mechanisms of its immunomodulation are still unclear. In the present study, we investigated if such immunonutrition could affect T-cell and natural killer (NK) cell functions, with particular focus on type 17 helper T (Th17) cells and NK cell-activating markers, in patients with esophageal and gastric cancer and in healthy volunteers. Methods Patients ( n = 22) and healthy volunteers ( n = 10) were orally administered an immunonutritional diet (Impact, 750 mL/d) in addition to a conventional diet for 5 d. The expression of NK cell-activation markers (NKG2D, CD16, CD107a, NKp30, NKp44, and NKp46), frequency of CD56 dim NK, Th17, and regulatory T cells, and trastuzumab-mediated antibody-dependent cell-mediated cytotoxicity were analyzed before and after immunonutrition. Results Immunonutrition significantly enhanced antibody-dependent cell-mediated cytotoxic activity as an NK cell function, paralleling the upregulated expression of NKG2D and CD16 and increased frequency of CD56 dim NK cells. Furthermore, the immunonutrition significantly increased the frequency of Th17 cells. Conclusion Immunonutrition modulates NK and T-cell–mediated immunity.