Expression of interleukin-12 in synovial tissue from patients with rheumatoid arthritis.

白细胞介素-12作为干扰素-γ（IFN-γ）-显性T细胞细胞因子反应的因子在类风湿性关节炎（RA）患者的滑膜组织中的重要性进行了检查。RT-PCR结果显示，RA患者滑膜组织IL-12 p40 mRNA表达较OA组织强，RA患者游离组织细胞在培养液中自发释放可检测量的IL-12 p70，而OA组织产生IL-12的能力有限。免疫组化显示IL-12阳性细胞主要分布于RA滑膜的衬里下层，且多表达CD 68抗原。RA滑膜组织细胞产生IFN-γ的水平被IL-12有效地和选择性地增强。IL-2扩增的滑膜T细胞产生IFN-γ的能力通过与IL-12共刺激而增强，通过抗IL-12而减弱，而IL-4不影响。这些数据表明，IL-12，主要由巨噬细胞系细胞产生，可能参与IFN-γ占主导地位的细胞因子的生产与慢性RA关节浸润T细胞。

The importance of interleukin-12 as a factor in the interferon-gamma (IFN-gamma) -dominant T cell cytokine response in the synovial tissue of patients with rheumatoid arthritis (RA) was examined. Synovial tissues from RA patients more strongly expressed IL-12 p40 mRNA than did osteorthritis (OA) tissues, as determined by RT-PCR.Dissociated tissue cells from RA patients sspontaneously released detectable amounts of IL-12 p70 in culture, whereas production of IL-12 by OA tissues was limited. By immunohistochemical analysis, IL-12-producing cells were localized mainly in the sublining layr of RA synovium, and mostly expressed the CD68 antigen. Levels of IFN-gamma production by RA synovial tissue cells were potently and selectively enhanced by IL-12. The ability of IL-2-expanding synovial T cells to produce IFN-gamma was augmented by costimulation with IL-12 and diminished by anti-IL-12, while it was not affected by IL-4. These dada suggest that IL-12, produced mainly by macrophage-lineage cells, may be involved in IFN-gamma dominant cytokine production by infiltrating T cells in joints with chronic RA.