严重烧伤患者T淋巴细胞免疫功能变化及其与患者预后的关系

Changes in T lymphocyte immunity and their relationship with prognosis of patients with severe burns

目的明确严重烧伤后患者外周血T淋巴细胞免疫功能的变化规律,并探讨其在患者不良预后中的临床意义。方法对106例烧伤总体表面积(TBSA)≥30%的患者进行动态观察,对所采集临床病例资料进行分析。试验分组:(1)按烧伤面积将患者分为3组:Ⅰ组41例(TBSA 30%～49%),Ⅱ组34例(TBSA 50%～69%),Ⅲ组31例(TBSA 70%～99%);(2)将59例并发脓毒症患者根据其预后分为死亡组(17例)与存活组(42例)。同时设正常对照组(25位健康献血员)。分别于烧伤后1、3、7、14、21天采集患者外周静脉血,分离外周血T淋巴细胞,分别检测T淋巴细胞增殖活性和T淋巴细胞孵育上清中白细胞介素(IL)-2分泌水平等。结果与正常对照组比较,严重烧伤患者各烧伤面积组外周血T淋巴细增殖活性及IL-2表达水平均明显降低,Ⅰ组与Ⅲ组比较存在显著差异(P<0.01)。死亡组患者T淋巴细胞增殖活性及IL-2表达水平在伤后3～21天明显低于存活组(P<0.01或P<0.05)。结论严重烧伤后T淋巴细胞免疫功能明显受抑,机体免疫功能障碍程度与烧伤面积和患者预后密切相关。

Objective To observe the changes in T lymphocyte-mediated immunity in severely burned patients,and to investigate their relationship with patients＇ prognosis.Methods One hundred and six patients with total burn surface area（TBSA） larger than 30% were included in the present study,and they were divided into three burn size groups： 30%-49% TBSA（group Ⅰ,n=41）,50%-69% TBSA（group Ⅱ,n=34）,and 70% TBSA（group Ⅲ,n=31）.According to the definition of sepsis in burns,59 patients were developed into septic complications,then the septic patients were further divided into non-survival group（n=17） and survival group（n=42）.Healthy volunteers served as normal controls（n=25）.The periphery blood samples were collected on postburn day（PBD） 1,3,7,14,and 21,respectively.The blood samples were used to isolate T cells,and T cell proliferation assay was performed by thiazolyl blue,and interleukin（IL）-2 released into supernatants were determined by ELISA kits for human after culturing the T cells.Results The T cell proliferative activity in response to phytohemagglutinine and protein levels of IL-2 in supernatants in burn-injured patients were significantly suppressed on PBD 1-21 compared with normal controls,and there were obvious differences in both T cell proliferative activity and IL-2 release between group Ⅰ and group Ⅲ（P0.01）.Among septic patients,the T cell proliferative activity in response to phytohemagglutinine and IL-2 release in the survival group were markedly higher than those with fatal outcome on PBD 3-21（P0.01 or P0.05）.Conclusion Suppression of T lymphocyte immune function is induced by severe burn injury.The immunosuppressive state of T lymphocytes is related to the extent of burn injury and poor outcome in burned patients.