James S P, Mullin G E, Kanof M E, Zeitz M
Laboratory of Clinical Investigation, National Institute of Allergy and Infectious Diseases, Bethesda, Md.
Immunol Res. 1991;10(3-4):230-8. doi: 10.1007/BF02919698.
The findings presented above and in other studies provide substantial evidence that lymphocytes in the intestinal lamina propria differ from lymphocyte populations in the circulation or in other tissue sites in a number of ways. First, lamina propria lymphocytes are phenotypically distinct and have evidence of activation. Lymphocytes in the intestinal lamina propria are different in their potential for expression of lymphokine gene products, since activated cells from the lamina propria have high expression of mRNA for IL-2, IL-4, IL-5 and IFN-gamma in comparison to circulating lymphocytes. Mesenteric lymph node T cells also differ from circulating lymphocytes in their high expression of IL-4 and IL-5 mRNA. A further difference between mesenteric lymph node and lamina propria T cells is that the former are capable of proliferating in response to IL-4, whereas the latter are not. These phenotypic and mRNA differences of lamina propria lymphocytes also correlate well with their high helper activity in vitro for immunoglobulin synthesis in the pokeweed mitogen system. Finally, lamina propria T cells at a site of inflammation are able to provide high helper activity in response to specific antigens. These observations are all consistent with the conclusion that T cells in the lamina propria are pleomorphic, but are highly enriched for subpopulations of activated memory cells that are geared for effector functions. These functions are likely to be critical in maintaining normal host defense in the mucosal environment.
上述研究结果以及其他研究提供了大量证据，表明肠道固有层中的淋巴细胞在许多方面与循环系统或其他组织部位的淋巴细胞群体不同。首先，固有层淋巴细胞在表型上是独特的，且有活化的证据。肠道固有层中的淋巴细胞在淋巴因子基因产物的表达潜力方面存在差异，因为与循环淋巴细胞相比，固有层中的活化细胞具有高表达的IL-2、IL-4、IL-5和IFN-γ mRNA。肠系膜淋巴结T细胞在IL-4和IL-5 mRNA的高表达方面也与循环淋巴细胞不同。肠系膜淋巴结T细胞和固有层T细胞之间的另一个差异是，前者能够对IL-4作出增殖反应，而后者则不能。固有层淋巴细胞的这些表型和mRNA差异也与其在体外对商陆有丝分裂原系统中免疫球蛋白合成的高辅助活性密切相关。最后，炎症部位的固有层T细胞能够对特定抗原作出高辅助活性反应。这些观察结果均与以下结论一致，即固有层中的T细胞是多形性的，但高度富集了适合效应功能的活化记忆细胞亚群。这些功能可能对维持黏膜环境中的正常宿主防御至关重要。
