人脐血多种细胞因子的含量检测及植物血凝素和脂多糖的影响

目的:通过检测人脐血血清多种细胞因子含量,观察植物血凝素(PHA)和脂多糖(LPS)的诱生影响,探讨这些细胞因子的免疫功能及移植物抗宿主病(GVHD)的发病机制。方法:采用双抗体夹心酶联免疫吸附法(ELISA),测定26份正常足月新生儿脐血及16例正常儿童外周血血清中白细胞介素4(IL-4)、IL-10、肿瘤坏死因子α(TNF-α)、γ干扰素(IFN-γ)、IL-12、IL-15、IL-18水平,以及PHA和LPS刺激后单个核细胞分泌上述细胞因子的诱生水平。结果:人脐血血清中IL-4的水平与正常外周血血清水平无显著差异(P＞0.05),脐血血清中IL-12的水平显著高于外周血血清(P＜0.05),其余5种细胞因子脐血血清水平均明显低于正常外周血血清水平(P＜0.05);PHA和LPS刺激后脐血单个核细胞分泌IL-4、IL-10、TNF-α、IFN-γ、IL-12、IL-15和IL-18的水平明显低于正常外周血(P＜0.05),尤以IL-4、TNF-α、IFN-γ、IL-15和IL-18非常明显。结论:脐血血清中上述细胞因子水平普遍低于正常外周血,以及脐血单个核细胞刺激后产生IL-4、IL-10、TNF-α、IFN-γ、IL-12、IL-15和IL-18等细胞因子水平的不足,表明脐血细胞免疫功能不成熟,是脐血移植后GVHD发生率低及程度轻的主要原因之一。

Levels of cytokines in human umbilical cord blood serum and in cultured mononuclear cells isolated from cord blood induced by phytohemagglutinin and lipopolysaccharide

AIM:To determine the levels of varied cytokines in human umbilical cord blood (UCB) serum and in cultured mononuclear cells isolated from cord blood induced by phytohemagglutinin and lipopolysaccharide(PHA and LPS), and to explore the immunity function of these cytokines in human umbilical cord blood and the mechanism of graft-versus-host disease (GVHD). METHODS:The serum values and the values of PHA and LPS-induced mononuclear cells(MNC) of interleukin-4(IL-4), IL-10,tumor necrosis factor α(TNF-α), interferon-γ(IFN-γ),IL-12,IL-15 and IL-18 were determined by ELISA in UCB of 26 samples, and compared with normal children peripheral blood (PB) of 16 samples. RESULTS:The level of IL-4 in UCB serum was similar to PB serum(P＞0.05). The level of IL-12 in PB serum was higher than that of PB serum(P＜0.05). The levels of TNF-α, IFN-γ, IL-12,IL-15 and IL-18 in CB serum were markedly higher than those in PB serum(P＜0.05). The induced levels of above-mentioned cytokines in CBMNC were significantly lower than that in PBMNC(P＜0.05). CONCLUSION:The lower levels of most above-mentioned cytokines in human CB serum and the lower induced levels in CBMNC showed that immunity functions of UCB were immature, which provide insight into the low incidence of graft-versus-host disease.