Suárez Lina J, Arboleda Silie, Angelov Nikola, Arce Roger M
Departamento de Ciencias Básicas y Medicina Oral, Universidad Nacional de Colombia, Bogotá, Colombia.
Department of Periodontics and Dental Hygiene, School of Dentistry, University of Texas Health Science Center at Houston, Houston, TX, United States.
Front Immunol. 2021 Jul 5;12:705206. doi: 10.3389/fimmu.2021.705206. eCollection 2021.
Different body systems (epidermis, respiratory tract, cornea, oral cavity, and gastrointestinal tract) are in continuous direct contact with innocuous and/or potentially harmful external agents, exhibiting dynamic and highly selective interaction throughout the epithelia, which function as both a physical and chemical protective barrier. Resident immune cells in the epithelia are constantly challenged and must distinguish among antigens that must be either tolerated or those to which a response must be mounted for. When such a decision begins to take place in lymphoid foci and/or mucosa-associated lymphoid tissues, the epithelia network of immune surveillance actively dominates both oral and gastrointestinal compartments, which are thought to operate in the same immune continuum. However, anatomical variations clearly differentiate immune processes in both the mouth and gastrointestinal tract that demonstrate a wide array of independent immune responses. From single vs. multiple epithelia cell layers, widespread cell-to-cell junction types, microbial-associated recognition receptors, dendritic cell function as well as related signaling, the objective of this review is to specifically contrast the current knowledge of oral versus gut immune niches in the context of epithelia/lymphoid foci/MALT local immunity and systemic output. Related differences in 1) anatomy 2) cell-to-cell communication 3) antigen capture/processing/presentation 4) signaling in regulatory vs. proinflammatory responses and 5) systemic output consequences and its relations to disease pathogenesis are discussed.
不同的身体系统（表皮、呼吸道、角膜、口腔和胃肠道）持续直接接触无害和/或潜在有害的外部因子，在整个上皮组织中表现出动态且高度选择性的相互作用，上皮组织兼具物理和化学保护屏障的功能。上皮组织中的常驻免疫细胞不断受到挑战，必须区分那些必须耐受的抗原和那些必须引发免疫反应的抗原。当这种决策在淋巴小结和/或黏膜相关淋巴组织中开始发生时，免疫监视的上皮网络积极主导口腔和胃肠道区域，这两个区域被认为在相同的免疫连续体中运作。然而，解剖学差异明显区分了口腔和胃肠道中的免疫过程，这些过程表现出广泛的独立免疫反应。从单层与多层上皮细胞层、广泛的细胞间连接类型、微生物相关识别受体、树突状细胞功能以及相关信号传导等方面来看，本综述的目的是在局部上皮/淋巴小结/黏膜相关淋巴组织免疫和全身输出的背景下，具体对比口腔与肠道免疫微环境的现有知识。讨论了在1）解剖学、2）细胞间通讯、3）抗原捕获/处理/呈递、4）调节性与促炎性反应中的信号传导以及5）全身输出后果及其与疾病发病机制的关系等方面的相关差异。
