Revillard J P, Cozon G, Czerkinsky C
Laboratoire d'Immunologie, INSERM U80 CNRS URA 1177 UCBL, Hôpital E. Herriot, Lyon, France.
Dev Biol Stand. 1992;77:31-7.
Orally administered antigens reach the lymphoid tissue in Peyer's patches in the gut where they initiate an immune response with clonal expansion of antigen-specific T and B cells. Activated T cells migrate through lymph and blood to intestinal epithelium (intra-epithelial leukocytes) whereas activated B cells migrate to the lamina propria, other mucosae and exocrine glands where they differentiate into plasma cells secreting polymeric IgA1 or IgA2. These antibodies are transported across the epithelial cells after binding to a poly-Ig receptor, then excreted in the lumen as secretory IgA. Reciprocal interactions have been demonstrated between lymphoid and epithelial cells in the mucosae. Oral administration of antigens in different experimental models may induce the production of secretory antibodies and/or systemic unresponsiveness with suppression of delayed-type hypersensitivity or specific IgG and IgE antibody production or both. New strategies are currently being explored for the development of oral vaccines using recombinant antigens or viral vectors (e.g. pox-viruses, vaccinia virus, cholera toxin B subunit etc.). Conversely, immunomodulating compounds or procedures which could enhance specific oral tolerance in association with antigen would have considerable therapeutic applications in auto-immune diseases and allergy.
口服抗原到达肠道派尔集合淋巴结中的淋巴组织，在那里它们通过抗原特异性T细胞和B细胞的克隆扩增引发免疫反应。活化的T细胞通过淋巴和血液迁移到肠上皮（上皮内白细胞），而活化的B细胞迁移到固有层、其他黏膜和外分泌腺，在那里它们分化为分泌聚合型IgA1或IgA2的浆细胞。这些抗体在与多聚Ig受体结合后穿过上皮细胞，然后作为分泌型IgA排泄到管腔中。已证实黏膜中的淋巴样细胞和上皮细胞之间存在相互作用。在不同实验模型中口服抗原可能诱导分泌性抗体的产生和/或全身性无反应性，同时抑制迟发型超敏反应或特异性IgG和IgE抗体的产生，或两者兼而有之。目前正在探索利用重组抗原或病毒载体（如痘病毒、牛痘病毒、霍乱毒素B亚基等）开发口服疫苗的新策略。相反，与抗原相关的能够增强特异性口服耐受性的免疫调节化合物或程序在自身免疫性疾病和过敏症中具有相当大的治疗应用价值。
