Hultman C S, Cairns B A, deSerres S, Frelinger J A, Meyer A A
Department of Surgery, University of North Carolina, Chapel Hill 27599-7210, USA.
Surgery. 1995 Aug;118(2):421-9; discussion 429-30. doi: 10.1016/s0039-6060(05)80354-x.
Cytotoxic lymphocytes (CTLs) are an important component of immune function, involved in antigen recognition and resistance to viral infection. Burn injury suppresses cell-mediated immunity, induces allograft tolerance, and increases the risk of viral infection, but the mechanisms are not well understood. This study analyzes the effect of burn size and burn wound excision on CTL activity.
Anesthetized CBA mice (n = 12) received a 0%, 20%, or 40% body surface area contact burn. Additional mice (n = 16) received a 40% burn that was totally, partially, or not excised 72 hours after burn. Excised areas were covered with normal, syngeneic skin. Two weeks later harvested splenocytes were cocultured with allogeneic stimulators. CTL activity was determined by a 51Cr release assay, in which CTL effectors were tested on allogeneic, radiolabeled targets. Dilution curves of CTL activity were compared by ANOVA:
Both 20% and 40% burns significantly inhibited CTL activity (p < 0.05). Total but not partial excision of a 40% burn restored CTL activity (p < 0.01). Both total and partial wound excision also improved survival (p < 0.05).
Burn injury inhibits CTL activity in a size-dependent manner, and total wound excision significantly improves both CTL function and survival after injury. This study suggests a mechanism for the immunosuppressive effects of burn injury and provides an immunologic rationale for early, complete burn wound excision.
细胞毒性淋巴细胞（CTLs）是免疫功能的重要组成部分，参与抗原识别和抗病毒感染。烧伤会抑制细胞介导的免疫，诱导同种异体移植耐受，并增加病毒感染风险，但其机制尚不清楚。本研究分析烧伤面积和烧伤创面切除对CTL活性的影响。
将麻醉后的CBA小鼠（n = 12）进行0%、20%或40%体表面积的接触烧伤。另外的小鼠（n = 16）在烧伤72小时后接受40%的烧伤，然后分别进行全部、部分切除或不切除。切除区域覆盖正常的同基因皮肤。两周后，收获脾细胞并与同种异体刺激物共培养。通过51Cr释放试验测定CTL活性，其中CTL效应细胞在同种异体、放射性标记的靶细胞上进行检测。通过方差分析比较CTL活性的稀释曲线。
20%和40%的烧伤均显著抑制CTL活性（p < 0.05）。40%烧伤的全部切除而非部分切除可恢复CTL活性（p < 0.01）。全部和部分创面切除也提高了生存率（p < 0.05）。
烧伤以面积依赖的方式抑制CTL活性，全创面切除可显著改善损伤后的CTL功能和生存率。本研究揭示了烧伤免疫抑制作用的机制，并为早期、彻底切除烧伤创面提供了免疫学依据。
