淋巴细胞缺陷对内毒素血症小鼠腹腔巨噬细胞活化的影响

Effects of lymphocytes defect on activation of peritoneal macrophages in mice with endotoxemia

目的观察淋巴细胞缺陷对内毒素血症小鼠腹腔巨噬细胞活化的影响。方法采用腹腔注射脂多糖(LPS)建立Balb/c小鼠和T、B细胞缺陷的重症联合免疫缺陷(SCID)小鼠内毒素血症模型,ELISA检测2种小鼠腹腔灌洗液TNF-α和IL-10水平,实时荧光定量PCR检测腹腔巨噬细胞(peritoneal macrophage,PMa)TNF-α、IL-10及丝裂原蛋白激酶磷酸酶-1(mito-gen-activated protein kinase phosphatase-1,MKP-1)mRNA表达;ELISA检测Balb/c及SCID小鼠PMa体外刺激后细胞因子分泌情况。结果 LPS注射后1 h,SCID小鼠腹腔灌洗液TNF-α水平高于Balb/c小鼠,注射后3 h,IL-10水平低于Balb/c小鼠;LPS注射前及注射后,SCID小鼠PMa TNF-αmRNA表达高于Balb/c小鼠PMa,IL-10 mRNA表达低于Balb/c小鼠PMa;体外实验LPS刺激下,SCID小鼠PMa较Balb/c小鼠PMa分泌更多的TNF-α,IL-10的分泌却偏少。LPS注射前及注射后,Balb/c小鼠PMa MKP-1 mRNA表达均明显高于SCID小鼠。结论淋巴细胞缺陷导致内毒素血症小鼠腹腔巨噬细胞活性的增加,淋巴细胞抑制巨噬细胞的活化并可能调控其发育及成熟;MKP-1表达的减少可能是淋巴细胞缺陷导致腹腔巨噬细胞活性增加的分子机制之一。

This study aimed to investigate the effects of lymphocytes defect on activation of peritoneal macrophages in mice with endotoxemia.Endotoxemia models of Balb/c mice and severe combined immunodeficiency（SCID） mice were established by injecting LPS intraperitoneally.Peritoneal fluids of both mice were collected for testing peritoneal TNF-α and IL-10 by ELISA,while peritoneal macrophages（PMa） were used for testing TNF-α,IL-10 and mitogen-activated protein kinase phosphatase-1（MKP-1） mRNA expression by real-time PCR.PMa from both mice were stimulated by LPS in vitro,and supernatants were tested for TNF-α and IL-10 by ELISA.For SCID mice,the levels of peritoneal TNF-α were higher at 1 h but the levels of peritoneal IL-10 were lower at 3 h after LPS injection,as compared with Balb/c mice.TNF-α mRNA expression of PMa from SCID mice was higher but IL-10 mRNA expression was lower than those of PMa from Balb/c mice after and even before LPS injection.After LPS stimulation in vitro,PMa from SCID mice secreted more TNF-α but less IL-10,as compared with PMa from Balb/c mice.MKP-1 mRNA expression of PMa from Balb/c mice were higher than those from SCID mice before and after LPS injection.Altogether,with defective lymphocytes,activities of PMa increase in SCID mice with endotoxemia.Lymphocytes suppress macrophages activation and may regulate macrophages＇ development,and they may act through increasing MKP-1 expression of macrophages.