Department of Nutrition, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Int J Obes (Lond). 2012 Aug;36(8):1072-7. doi: 10.1038/ijo.2011.208. Epub 2011 Oct 25.
Obesity is an independent risk factor for morbidity and mortality from pandemic influenza H1N1. Influenza is a significant public health threat, killing an estimated 250,000-500,000 people worldwide each year. More than one in ten of the world's adult population is obese and more than two-thirds of the US adult population is overweight or obese. No studies have compared humoral or cellular immune responses to influenza vaccination in healthy weight, overweight and obese populations despite clear public health importance.
The study employed a convenience sample to determine the antibody response to the 2009-2010 inactivated trivalent influenza vaccine (TIV) in healthy weight, overweight and obese participants at 1 and 12 months post vaccination. In addition, activation of CD8⁺ T cells and expression of interferon-γ and granzyme B were measured in influenza-stimulated peripheral blood mononuclear cell (PBMC) cultures.
Body mass index (BMI) correlated positively with higher initial fold increase in IgG antibodies detected by enzyme-linked immunosorbent assay to TIV, confirmed by HAI antibody in a subset study. However, 12 months post vaccination, higher BMI was associated with a greater decline in influenza antibody titers. PBMCs challenged ex vivo with vaccine strain virus, demonstrated that obese individuals had decreased CD8⁺ T-cell activation and decreased expression of functional proteins compared with healthy weight individuals.
These results suggest obesity may impair the ability to mount a protective immune response to influenza virus.
肥胖是大流行性流感 H1N1 发病和死亡的独立危险因素。流感是一个重大的公共卫生威胁，每年估计在全球造成 25 万至 50 万人死亡。世界上超过十分之一的成年人口肥胖，超过三分之二的美国成年人口超重或肥胖。尽管具有明显的公共卫生重要性，但没有研究比较健康体重、超重和肥胖人群对流感疫苗接种的体液或细胞免疫反应。
该研究采用便利抽样法，在接种后 1 个月和 12 个月时，确定健康体重、超重和肥胖参与者对 2009-2010 年灭活三价流感疫苗（TIV）的抗体反应。此外，还测量了流感刺激外周血单个核细胞（PBMC）培养物中 CD8⁺ T 细胞的激活和干扰素-γ和颗粒酶 B 的表达。
体重指数（BMI）与酶联免疫吸附试验检测到的 TIV 初始 IgG 抗体的更高倍数增加呈正相关，亚组研究中通过血凝抑制抗体得到证实。然而，接种后 12 个月时，较高的 BMI 与流感抗体滴度的下降幅度更大相关。体外挑战 PBMC 疫苗株病毒表明，与健康体重个体相比，肥胖个体的 CD8⁺ T 细胞激活减少，功能蛋白表达减少。
这些结果表明，肥胖可能会损害人体对流感病毒产生保护性免疫反应的能力。
