烫伤后肠壁组织T淋巴细胞和浆细胞数量的变化

Experimental study on changes in T lymphocytes and IgA plasmocytes in intestinal wall after scald injury

目的：了解烧伤后肠壁组织T淋巴细胞和IgA浆细胞数量的变化与伤后肠道细菌易位及肠源性脓毒症发生、发展的关系。方法：Wistar大鼠50只，随机分成对照组（l只）和烫伤组（40只）。烫伤组动物背部脱毛，将背部浸于沸水中12秒钟，造成40％体表面积Ⅲ度烫伤，分别于伤后第1、3、7和10日处死，留取标本；对照组动物不烫伤，于处理后第1日处死，留取标本。采用免疫组化方法分别测定回肠固有层和粘膜层CD3+、CD4+和CD8+淋巴细胞以及IgA浆细胞数量，并测定肠道细菌IgA包被率和肠道细菌易位率。结果：伤后肠壁组织中CD3+、CD4+T淋巴细胞和lgA浆细胞的数量明显减少，CD4+／CD8+比值和肠道细菌IgA包被率亦明显降低，而肠道细菌易位率则明显升高。结论：肠壁组织中T淋巴细胞和IgA浆细胞数量减少、肠道细菌IgA包被率降低与肠道细菌易位率升高有密切关系，其在烧伤后肠源性脓毒症的发生和发展中可能具有重要意义。

Objective:To observe changes in T lymphocyte and IgA plasmocytes in intestinal walla fier scald injury,and to investigate the relationship between these changes and the development of gut-- derived sepsis. Methods:Fifty Wistar rats were randomly divided into 2 groups =sham controls (n= 10)and 40% TBSA M scald injury (n=40). Animals were sacrificed on postburn days l, 3, 7 and 10,respectively. The number of T lymphocytes (CD3+CD4+ and CD8+ ) and lgA plasmocytes in lieal wall weremeasured by immunohistochemical methods. The IgA coat rate of intestinal bacteria and the incidence ofbacterial translocation were also assayed. Results: After scald injury,the number of CD3+,CD4+ T cellsand CD4+/CD8+ ratio were markedly decreased,and IgA coat rate of intestinal bacteria was also reducedcompared with the controls. However, incidences of bacterial translocation from gastrointestinal tractwere increased following severe burns. Conclusions:The results indicate that decrease in the number ofT lymphocytes and IgA plasmocytes may play an important role in the development of gut - derived sepsis after burn injury.