Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea.
Seoul feed Co., Ltd., Incheon 405-819, Republic of Korea.
Poult Sci. 2017 May 1;96(5):1063-1070. doi: 10.3382/ps/pew382.
Organic acids have long been known for their beneficial effects on growth performance in domestic animals. However, their impact on immune responses against viral antigens in chickens is unclear. The present study aimed to investigate immunological parameters in broilers immunized with a H9N2 vaccine and/or fed a diet containing organic acids (citric, formic, and lactic acids). We allotted 1-day-old broilers into 4 groups: control (C), fed a diet supplemented with organic acids (O), administered a H9N2 vaccine (V), and fed a diet supplemented with organic acids and administered a H9N2 vaccine (OV). Blood and spleen samples were taken at 2, 7 and 14 d post vaccination (DPV). At 14 DPV, total and H9N2-specific IgG levels were significantly lower in the OV group than in the V group. However, it was intriguing to observe that at 2 DPV, the percentage of CD4+CD25+ T cells was significantly higher in the OV group than in the other groups, indicating the potential induction of regulatory T cells by organic acids. In contrast, at 2 DPV, the percentage of CD4+CD28+ T cells were significantly lower in the OV group than in the other groups, suggesting that CD28 molecules are down-regulated by the treatment. The expression of CD28 on CD4+ T cells, up-regulated by the stimulation with phorbol 12-myristate 13-acetate (PMA) and ionomycin (Iono), was inhibited upon organic acid treatment in OV group. In addition, the proliferation of lymphocytes, stimulated with formalin-inactivated H9N2, was significantly higher in the V group than in the OV group. Alpha 1-acid glycoprotein (AGP) production was significantly lower in the OV group than in the V group, suggesting that the organic acids inhibited the inflammation caused by the vaccination. Overall, induction of regulatory CD4+CD25+ T cells, coinciding with the decrease of H9N2-specific antibodies, was observed in broilers fed organic acids.
有机酸对家畜的生长性能一直以来都有着有益的影响。然而，它们对鸡的抗病毒抗原免疫反应的影响尚不清楚。本研究旨在研究用 H9N2 疫苗免疫的肉鸡和/或用含有有机酸（柠檬酸、甲酸和乳酸）的日粮喂养的肉鸡的免疫参数。我们将 1 日龄肉鸡分为 4 组：对照组（C）、用有机酸日粮饲养组（O）、接种 H9N2 疫苗组（V）和用有机酸日粮饲养并接种 H9N2 疫苗组（OV）。在接种后 2、7 和 14 天（DPV）采集血液和脾脏样本。在 14 DPV 时，OV 组的总 IgG 和 H9N2 特异性 IgG 水平明显低于 V 组。然而，有趣的是，在 2 DPV 时，OV 组的 CD4+CD25+T 细胞百分比明显高于其他组，表明有机酸可能诱导调节性 T 细胞。相反，在 2 DPV 时，OV 组的 CD4+CD28+T 细胞百分比明显低于其他组，表明 CD28 分子被处理下调。经佛波醇 12-肉豆蔻酸 13-醋酸盐（PMA）和离子霉素（Iono）刺激后，CD4+T 细胞上 CD28 的表达上调，而在用有机酸处理 OV 组时，其表达受到抑制。此外，用福尔马林灭活的 H9N2 刺激的淋巴细胞增殖在 V 组中明显高于 OV 组。OV 组的α 1-酸性糖蛋白（AGP）产生明显低于 V 组，表明有机酸抑制了疫苗接种引起的炎症。总的来说，在饲喂有机酸的肉鸡中观察到调节性 CD4+CD25+T 细胞的诱导，同时 H9N2 特异性抗体减少。
