Obesity and Metabolic Syndrome Group, Endocrinology Department, University of São Paulo Medical School General Hospital, São Paulo, Brazil.
Obes Surg. 2011 Jan;21(1):112-8. doi: 10.1007/s11695-010-0250-8.
Obesity is related to a higher rate of infections and some types of cancer. Here we analyzed the impact of obesity and weight loss induced by Roux-en-Y gastric bypass (RYGB) on immunological parameters, i.e., cytokine productions and natural killer cell function.
We analyzed 28 morbidly obese patients before and 6 months after RYGB. Biochemical parameters were analyzed in plasma. The percent of natural killer (NK) cells, their cytotoxicity, and the production of cytokines by peripheral blood mononuclear cells were analyzed. The percent of NK cells was determined by flow cytometry and cytokine production determined by enzyme-linked immunosorbent assay. NK cytotoxicity was determined by the lactate dehydrogenase release assay.
The weight loss 6 months following surgery was 35.3 ± 4.5 kg. RYGB also improves biochemical parameters. No significant difference was found in the percent of NK cells after surgery. We found an increase in the production of interferon-γ, interleukin (IL)-12 and IL-18, but not in IL-2, 6 months after RYGB. Cytotoxic activity of NK cells was significantly enhanced 6 months after RYGB [17.1 ± 14.7% before RYGB vs 51.8 ± 11.3% at 6 months after, at 40:1 effector to target cell ratio; p < 0.001]. We observed significant post-surgical improvement in the cytotoxic activity curve in 22 out of 28 patients (78.6%), irrespective of the target to effector cell ratio.
The weight loss induced by RYGB modifies the production of cytokines related with NK cell function and improves its activity.
肥胖与更高的感染率和某些类型的癌症有关。在这里，我们分析了肥胖和 Roux-en-Y 胃旁路术（RYGB）引起的体重减轻对免疫参数的影响，即细胞因子产生和自然杀伤细胞功能。
我们分析了 28 名病态肥胖患者在 RYGB 前后 6 个月的情况。在血浆中分析生化参数。分析外周血单个核细胞的自然杀伤（NK）细胞的百分比、其细胞毒性和细胞因子的产生。通过流式细胞术测定 NK 细胞的百分比，通过酶联免疫吸附试验测定细胞因子的产生。通过乳酸脱氢酶释放测定法测定 NK 细胞的细胞毒性。
手术后 6 个月的体重减轻了 35.3 ± 4.5kg。RYGB 还改善了生化参数。手术后 NK 细胞的百分比没有明显差异。我们发现手术后 6 个月干扰素-γ、白细胞介素（IL）-12 和 IL-18 的产生增加，但 IL-2 没有增加。手术后 6 个月，NK 细胞的细胞毒性活性显著增强[RYGB 前为 17.1 ± 14.7%，6 个月后为 51.8 ± 11.3%，在 40:1 的效应细胞与靶细胞比；p<0.001]。我们观察到 28 名患者中的 22 名（78.6%）在手术后 NK 细胞活性曲线有显著改善，而与靶细胞与效应细胞比无关。
RYGB 引起的体重减轻改变了与 NK 细胞功能相关的细胞因子的产生，并提高了其活性。
