Immune recovery after fluid resuscitation in rats with severe hemorrhagic shock

严重失血性休克大鼠液体复苏后的免疫修复（英文）

Objective： To investigate the effects of resuscitation with normal saline（NS）, hypertonic saline（HTS）, and hydroxyethyl starch（HES） on regulatory T cells（Tregs）, helper T 1（Th1）/Th2 and cytotoxic T 1（Tc1）/Tc2 profiles in the treatment of hemorrhagic shock. Methods： Rats subjected to severe hemorrhagic shock were resuscitated for 30 min with NS（n=8）, HTS（n=8）, or HES（n=8）; sham（n=8） and naive control（n=8） groups were used for comparison. Following fluid resuscitation, the whole shed blood was reinfused for 30 min, and the rats were observed with continuous hemodynamic monitoring for 120 min. CD4^＋CD25^＋Foxp3^＋ Treg proportions, Th1/Th2 and Tc1/Tc2 profiles in spleen were analyzed by three-color flow cytometry. Results： The proportion of CD4^＋CD25^＋Foxp3^＋ Tregs and ratios of Th1/Th2 and Tc1/Tc2 did not differ among control, sham, and HTS groups, but were significantly lower in NS and HES groups（both P0.05 vs. sham）; NS and HES levels were similar. The level of Tc1 was significantly increased in HTS（P0.05 vs. sham）, and levels of Tc2 were increased in NS, HES, and HTS groups compared to sham（all P0.05）, but did not differ from each other. Conclusions： HTS resuscitation has a greater impact on immune system recovery than NS or HES by preserving the proportion of Tregs and maintaining the balance between Th1/Th2 and Tc1/Tc2 cells in the spleen. Thus, HTS resuscitation provides potential immunomodulatory activity in the early stage after hemorrhagic shock.

目的:严重失血性休克大鼠模型早期阶段使用不同的液体复苏,比较脾脏组织中调节性T细胞(Tregs)、辅助性T细胞1(Th1)/Th2以及细胞毒性T细胞1(Tc1)/Tc2的不同变化,初步探讨其免疫修复机制。创新点:(1)脾脏为机体重要免疫器官,检测其中的免疫细胞变化,比外周血更具敏感性和特异性;(2)将免疫反应中多环节的免疫细胞变化进行协同分析,结果更具创新性和科学性,为临床上形成规范的救治方案提供了科学的实践资料。方法:将SD雄性大鼠随机分成5组,其中对照组和Sham组(假手术)仅作为比较,其余三组在建立严重失血性休克大鼠模型后,采用不同的液体复苏:等渗盐水(NS组)、高渗盐水(HTS组)和羟乙基淀粉(HES组)。然后再灌注30分钟,并持续监测血液动力学120分钟,最后心脏穿刺,取脾脏组织,通过三色荧光标记流式细胞术进一步分析CD4^+CD25^+Foxp3^+Treg细胞含量,以及Th1/Th2和Tc1/Tc2的比值。结论:液体复苏后大鼠脾脏中CD4^+CD25^+Foxp3^+Tregs细胞含量、Th1/Th2和Tc1/Tc2的比值在对照组、Sham组和HTS组中无差异,并都显著高于NS组和HES组。与Sham组比较,HTS组中Tc1水平明显升高,而NS组、HES组和HTS组中Tc2水平均有升高,且三组之间Tc2水平无差别。因此,对于维持脾脏中Treg细胞含量、Th1/Th2和Tc1/Tc2平衡的作用上,HTS液体复苏对免疫系统的影响大于NS和HES。综上所述,在失血性休克后的早期阶段HTS复苏可提供潜在的免疫修复作用。