Sakkas Lazaros I, Koussidis George, Avgerinos Efthimios, Gaughan John, Platsoucas Chris D
Department of Microbiology and Immunology, Temple University School of Medicine, Philadelphia, Pennsylvania 19140, USA.
Clin Diagn Lab Immunol. 2004 Jan;11(1):195-202. doi: 10.1128/cdli.11.1.195-202.2004.
Osteoarthritis (OA) is a heterogeneous disease which rheumatologists consider to be noninflammatory. However, recent studies suggest that, at least in certain patients, OA is an inflammatory disease and that patients often exhibit inflammatory infiltrates in the synovial membranes (SMs) of macrophages and activated T cells expressing proinflammatory cytokines. We report here that the expression of CD3zeta is significantly decreased in T cells infiltrating the SMs of patients with OA. The CD3zeta chain is involved in the T-cell signal transduction cascade, which is initiated by the engagement of the T-cell antigen receptor and which culminates in T-cell activation. Double immunofluorescence of single-cell suspensions derived from the SMs from nine patients with OA revealed significantly increased proportions of CD3epsilon-positive (CD3epsilon+) cells compared with the proportions of CD3zeta-positive (CD3zeta+) T cells (means +/- standard errors of the means, 80.48% +/- 3.92% and 69.02% +/- 6.51%, respectively; P = 0.0096), whereas there were no differences in the proportions of these cells in peripheral blood mononuclear cells (PBMCs) from healthy donors (94.73% +/- 1.39% and 93.79% +/- 1.08%, respectively; not significant). The CD3zeta+ cell/CD3epsilon+ cell ratio was also significantly decreased for T cells from the SMs of patients with OA compared with that for T cells from the PBMCs of healthy donors (0.84 +/- 0.17 and 0.99 +/- 0.01, respectively; P = 0.0302). The proportions of CD3epsilon+ CD3zeta+ cells were lower in the SMs of patients with OA than in the PBMCs of healthy donors (65.04% +/- 6.7% and 90.81% +/- 1.99%, respectively; P = 0.0047). Substantial proportions (about 15%) of CD3epsilon+ CD3zeta-negative (CD3zeta-) and CD3epsilon-negative (CD3epsilon-) CD3zeta- cells were found in the SMs of patients with OA. Amplification of the CD3zeta and CD3delta transcripts from the SMs of patients with OA by reverse transcriptase PCR consistently exhibited stronger bands for CD3delta cDNA than for CD3zeta cDNA The CD3zeta/CD3delta transcript ratio in the SMs of patients with OA was significantly lower than that in PBMCs from healthy controls (P < 0.0001). These results were confirmed by competitive MIMIC PCR. Immunoreactivities for the CD3zeta protein were detected in the SMs of 10 of 19 patients with OA, and they were of various intensities, whereas SMs from all patients were CD3epsilon+ (P = 0.0023). The decreased expression of the CD3zeta transcript and protein in T cells from the SMs of patients with OA relative to that of the CD3epsilon transcript is suggestive of chronic T-cell stimulation and supports the concept of T-cell involvement in OA.
骨关节炎（OA）是一种异质性疾病，风湿病学家认为它是非炎性的。然而，最近的研究表明，至少在某些患者中，OA是一种炎性疾病，并且患者的滑膜（SM）中常出现巨噬细胞和表达促炎细胞因子的活化T细胞的炎性浸润。我们在此报告，OA患者SM中浸润的T细胞中CD3ζ的表达显著降低。CD3ζ链参与T细胞信号转导级联反应，该反应由T细胞抗原受体的结合引发，并最终导致T细胞活化。对9例OA患者SM单细胞悬液进行双重免疫荧光检测发现，与CD3ζ阳性（CD3ζ+）T细胞比例相比，CD3ε阳性（CD3ε+）细胞比例显著增加（平均值±均值标准误分别为80.48%±3.92%和69.02%±6.51%；P = 0.0096），而健康供者外周血单个核细胞（PBMC）中这些细胞的比例无差异（分别为94.73%±1.39%和93.79%±1.08%；无显著性差异）。与健康供者PBMC中的T细胞相比，OA患者SM中的T细胞CD3ζ+细胞/CD3ε+细胞比值也显著降低（分别为0.84±0.17和0.99±0.01；P = 0.0302）。OA患者SM中CD3ε+ CD3ζ+细胞的比例低于健康供者PBMC中的比例（分别为65.04%±6.7%和90.81%±1.99%；P = 0.0047）。在OA患者的SM中发现相当比例（约15%）的CD3ε+ CD3ζ阴性（CD3ζ-）和CD3ε阴性（CD3ε-）CD3ζ-细胞。通过逆转录PCR扩增OA患者SM中的CD3ζ和CD3δ转录本，CD3δ cDNA的条带始终比CD3ζ cDNA的条带更强。OA患者SM中CD3ζ/CD3δ转录本比值显著低于健康对照的PBMC（P < 0.0001）。这些结果通过竞争性MIMIC PCR得到证实。在19例OA患者中的10例的SM中检测到CD3ζ蛋白的免疫反应性，其强度各不相同，而所有患者的SM均为CD3ε+（P = 0.0023）。与CD3ε转录本相比，OA患者SM中T细胞CD3ζ转录本和蛋白表达的降低提示T细胞受到慢性刺激，并支持T细胞参与OA的概念。
