【摘要】 目的：ＩＦＮ－γ是由被有丝分裂原或抗原所激活的Ｔ细胞和ＮＫ细胞所产生，它具有广泛的免疫调节活性，现认为ＩＬ－１２（外源性）是诱导 ＩＦＮ－γ产生的强诱导剂，并可促进静息 ＣＤ４＋Ｔ细胞朝向 Ｔｈ１表型分化，即诱导细胞免疫。目的是为了解由ＰＢＭＣ产生的内源性ＩＬ－１２是否在体外可诱导ＩＦＮ－γ的产生及通过何机制诱导细胞免疫。方法：用抗ＣＤ３抗体、ＰＨＡ、抗ＣＤ３抗体加抗ＣＤ２８抗体和抗原（ＭＬＣ）来检测被刺激的ＰＢＭ细胞的ＩＦＮ－γ的产生，同时也用ＩＬ－１２和ＩＬ－１２Ｒβ１的中和抗体来抑制ＩＦＮ－γ的产生。结果：激活的人ＰＢＭ中ＩＦＮ－γ分泌依赖于内源性ＩＬ－１２的产生，而且激活的Ｔ细胞可诱导ＡＰＣ细胞产生ＩＬ－１２，此过程是通过Ｔ细胞表面的ＣＤ４０Ｌ和ＡＰＣ的ＣＤ４０相互作用而实现。结论：这些结果提示，内源性ＩＬ－１２在正常宿主抗细胞内抗原的感染反应中起重要作用，在某些形式的自身免疫性疾病和移植排斥反应的免疫病理发生中也起中心作用。更多还原

【Abstract】 Objective: IFN-y is produced by both activated T and NK cells in response to mitogen or antigen and has a broad range of immunoregulatory activity. IL-12 has been described as a strong inducer of IFN-γproduction and promotes the differentiation of naive CD4+T cells toward the Th1 phenotype, priming them for IFN-γproduction, and consequent induction of cell-mediated immunity. Aim is to know endogenous production of IL,12 from PBMC inducing production of IFN-γin vitro, which is involving in mechanism of T cells to be activated. Methods: Induced IFT-γ secretion from human PBMC by stimulated with anti-CD3 , PHA, anti-CD3 plus anti-CD28 and antigen(MLC) Also inhibited IFN-γproduction by neutralizing antibodies to IL-12 and IL-12Rβ1 significantly. Results: IFN-γsecretion from human activated PBMC is endogenous IL-12dependent, and activated T cells induce the production of IL-12 from APC by a mechanism involving the interaction between CD40L on T cells and CD40 on APC. Conclusion: These results suggest that endogenous IL-12 plays an important role in the normal host defense against infection by a variety of intracellular pathogens and also plays a central role in the genesis of some forms of immunopathology including autoimmune diseases and transplantation rejections.更多还原