中文摘要：

目的观察TLR4配体脂多糖（LPS）对B细胞功能影响及相关的信号转导通路。方法利用免疫磁珠法分选小鼠脾脏CD19＋B细胞,体外用LPS刺激后,CBA（cytometric bead array）法检测B细胞分泌的Ig（immunoglobulin）亚型;流式细胞术（flow cytometry,FCM）检测B细胞表型;CBA法检测培养上清中细胞因子IL-6、IL-10、IL-12p70、TNF浓度。利用ERK、JNK、p38MAPK和NF-κB信号转导抑制剂检测B细胞内细胞因子分泌的信号转导通路。结果 LPS可以诱导B细胞产生IgG1-κ和IgM-κ抗体,上调B细胞表面CD40、CD80、CD86和MHCⅡ类分子的表达,促进IL-6、IL-10和TNF的高分泌。JNK、p38MAPK和NF-κB信号转导通路调控B细胞IL-6、IL-10和TNF的分泌。结论 LPS可以通过诱导抗体产生、上调共刺激分子表达和促进细胞因子分泌等多方面调节B细胞功能。

英文摘要：

Objective To observe the effects of lipopolysaccharide（LPS） on B cell function and the related signal transduction pathways.Methods Freshly purified splenic B cells（CD19＋ B） of mice were isolated by magnetic activated cell sorting.After stimulation with LPS,the culture supernatants were collected for immunoglobulin isotyping by cytometric bead array（CBA） technology.Flow cytometry was used to analyze costimulatory molecule expression and culture supernatants were also collected for measuring IL-6,IL-10,IL-12p70 and TNF by CBA technology.PD98059（ERK inhibitor）,SP600125（JNK inhibitor）,SB203580（p38 MAPK inhibitor） and PDTC（NF-κB inhibitor） were used to study the signal pathways for the induced secretion of IL-6,IL-10 and TNF in B cells.Results LPS induced IgG1-κ and IgM-κ production,up-regulated the expression of CD40,CD80,CD86 and MHC class Ⅱ,and promoted IL-6,IL-10 and TNF secretion by B cells.Furthermore,JNK,p38 MAPK,and NF-κB pathways regulated the secretion of IL-6,IL-10 and TNF in B cells.Conclusion LPS can regulate B cell function by inducing Ig production,cytokine secretion,and expression of costimulatory molecules.