Horiuchi Kiwamu, Saito Seiji, Sasaki Ryohei, Tomatsu Taisuke, Toyama Yoshiaki
Institute of Rheumatology, Tokyo Women's Medical University, Tokyo, Japan.
J Rheumatol. 2003 Aug;30(8):1799-810.
To investigate the expression of granzyme B (GrB) in normal and rheumatoid arthritis (RA) articular cartilage, and to analyze the relationship between the expression of GrB and apoptotic chondrocytes in RA cartilage.
Normal cartilage samples were obtained from 9 resected joints and RA cartilage samples were obtained from 12 patients with RA during joint replacement surgery. Cartilage sections were analyzed by immunohistochemistry for the presence of GrB, and the mRNA expression of GrB in chondrocytes was analyzed by in situ hybridization and nonquantitative and semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR). The expression of perforin (PFN) was also assessed. Apoptotic chondrocytes were detected using TUNEL staining and their morphology was examined using electron microscopy.
The immunohistochemical analyses revealed GrB and PFN expression in normal chondrocytes and a larger number of GrB and PFN-positive chondrocytes in RA cartilage. In situ hybridization and RT-PCR confirmed the expression of GrB and PFN mRNA, and semiquantitative RT-PCR showed elevated concentrations of GrB and PFN expression in RA chondrocytes. The distribution of GrB and PFN-positive cells in the RA cartilage samples was similar to that of apoptotic cells.
GrB and PFN expression is present in normal human articular chondrocytes and elevated in RA chondrocytes. The targets and precise functions of GrB expressed in chondrocytes remain to be determined, but GrB may be involved in the remodeling mechanism of matrix macromolecules and the endogenous degradation of RA cartilage.
研究颗粒酶B（GrB）在正常及类风湿关节炎（RA）关节软骨中的表达情况，并分析RA软骨中GrB表达与凋亡软骨细胞之间的关系。
从9例切除的关节中获取正常软骨样本，从12例RA患者行关节置换手术时获取RA软骨样本。通过免疫组织化学分析软骨切片中GrB的存在情况，通过原位杂交以及非定量和半定量逆转录聚合酶链反应（RT-PCR）分析软骨细胞中GrB的mRNA表达。同时评估穿孔素（PFN）的表达。使用TUNEL染色检测凋亡软骨细胞，并通过电子显微镜检查其形态。
免疫组织化学分析显示正常软骨细胞中有GrB和PFN表达，RA软骨中有更多GrB和PFN阳性软骨细胞。原位杂交和RT-PCR证实了GrB和PFN mRNA的表达，半定量RT-PCR显示RA软骨细胞中GrB和PFN表达浓度升高。RA软骨样本中GrB和PFN阳性细胞的分布与凋亡细胞相似。
正常人类关节软骨细胞中存在GrB和PFN表达，RA软骨细胞中表达升高。软骨细胞中表达的GrB的作用靶点和精确功能尚待确定，但GrB可能参与基质大分子的重塑机制以及RA软骨的内源性降解。
