Centre for Immunology and Infectious Disease, Barts and the London School of Medicine and Dentistry, 2 Newark Street, London E1 2AT, UK.
Biochem Soc Trans. 2011 Aug;39(4):1061-6. doi: 10.1042/BST0391061.
There are large numbers of T-cells in the mucosa of the intestine in healthy individuals. The stimulus for their presence is the normal gut microbiota. For unknown reasons, in patients with IBD (inflammatory bowel disease), there is inappropriate and chronic activation of mucosal T-cells which leads to gut damage and severe morbidity. In one form of IBD, namely Crohn's disease, the T-cells are probably responding to the microbiota. T-cell survival in the gut wall is dependent on pro-inflammatory cytokines and antibody-mediated inhibition of one of these cytokines, TNFα (tumour necrosis factor α), has shown efficacy in patients, thus encouraging investigations of other ways to control mucosal T-cell responses. In the present paper, we give a brief review of T-cell immunology in IBD and then discuss how two particular cytokines, namely IL-21 (interleukin 21), which is generally pro-inflammatory and important in gut T-cell survival and in maintaining Th17 cells, and TGFβ1 (transforming growth factor β1), which is generally immunosuppressive, play opposing roles in gut inflammation.
健康个体的肠道黏膜中有大量的 T 细胞。它们存在的刺激因素是正常的肠道微生物群。由于未知原因，在炎症性肠病（IBD）患者中，黏膜 T 细胞会发生不适当且慢性的激活，导致肠道损伤和严重的发病率。在一种形式的 IBD，即克罗恩病中，T 细胞可能对微生物群产生反应。T 细胞在肠道壁中的存活依赖于促炎细胞因子，而对其中一种细胞因子 TNFα（肿瘤坏死因子 α）的抗体介导抑制已在患者中显示出疗效，从而鼓励探索控制黏膜 T 细胞反应的其他方法。在本文中，我们简要回顾了 IBD 中的 T 细胞免疫学，然后讨论了两种特定的细胞因子，即通常具有促炎作用且对肠道 T 细胞存活和 Th17 细胞维持很重要的 IL-21（白细胞介素 21），以及通常具有免疫抑制作用的 TGFβ1（转化生长因子 β1），它们在肠道炎症中发挥相反的作用。
