Institute for Clinical Chemistry, Medical Faculty, University of Cologne, Kerpener Str. 62, 50924, Cologne, Germany.
Center for Biochemistry, Medical Faculty, University of Cologne, Joseph-Stelzmann-Str. 52, 50931, Cologne, Germany.
Biochem Biophys Res Commun. 2018 Sep 10;503(3):1273-1277. doi: 10.1016/j.bbrc.2018.07.036. Epub 2018 Jul 9.
We investigated the presence of autoantibodies against the extracellular matrix proteins thrombospondin-4 (TSP-4), cartilage oligomeric matrix protein (COMP), C-type lectin domain family 3 member A (CLEC3A), collagen II, collagen VI, matrilin-3, and fibrillin-2 in the serum of osteoarthritis (OA) patients. We compared those results with the presence of such antibodies in rheumatoid arthritis (RA) patients and in healthy donors (HD). Our study examines whether antibodies against extracellular proteins can be used as potential biomarkers to support the clinical diagnosis of OA. 10 OA, 10 RA patients and 10 HD were enrolled in this explorative cross-sectional study. SDS-PAGE and immunoblot were used to investigate the presence of antibodies against extracellular matrix proteins. The serum of 5/10 OA patients but 0/10 HD exhibited TSP-4 IgG isotype antibodies (P = 0.033). The serum of 8/10 OA patients but only 1/10 HD exhibited IgG isotype antibodies against TSP-4 or COMP (P = 0.005). The serum of 9/10 OA patients but only 1/10 HD exhibited IgG isotype antibodies against TSP-4, COMP or CLEC3A (P = 0.005). We found strong evidence for the presence of IgG isotype autoantibodies against the cartilage extracellular matrix proteins TSP-4, COMP and CLEC3A in OA. The detection of IgG isotype autoantibodies against TSP-4, COMP and CLEC3A may support the clinical diagnosis of OA. OA with autoantibodies against cartilage extracellular matrix proteins defines a new OA subgroup suggesting that patients with high concentrations of autoantibodies may benefit from an immune suppressive therapy.
我们研究了骨关节炎（OA）患者血清中是否存在针对细胞外基质蛋白血栓素-4（TSP-4）、软骨寡聚基质蛋白（COMP）、C 型凝集素结构域家族 3 成员 A（CLEC3A）、Ⅱ型胶原、Ⅵ型胶原、软骨基质蛋白 3 和原纤维蛋白 2 的自身抗体，并将这些结果与类风湿关节炎（RA）患者和健康供体（HD）进行了比较。我们的研究旨在探讨针对细胞外蛋白的抗体是否可作为支持 OA 临床诊断的潜在生物标志物。本探索性横断面研究纳入了 10 名 OA 患者、10 名 RA 患者和 10 名 HD。使用 SDS-PAGE 和免疫印迹法来研究针对细胞外基质蛋白的抗体存在情况。血清中 5/10 的 OA 患者但 0/10 的 HD 患者存在 TSP-4 IgG 同种型抗体（P=0.033）。10 名 OA 患者中有 8 名、而仅有 1 名 HD 患者存在针对 TSP-4 或 COMP 的 IgG 同种型抗体（P=0.005）。10 名 OA 患者中有 9 名、而仅有 1 名 HD 患者存在针对 TSP-4、COMP 或 CLEC3A 的 IgG 同种型抗体（P=0.005）。我们发现 OA 患者中存在针对软骨细胞外基质蛋白 TSP-4、COMP 和 CLEC3A 的 IgG 同种型自身抗体。针对 TSP-4、COMP 和 CLEC3A 的 IgG 同种型自身抗体的检测可能有助于 OA 的临床诊断。针对软骨细胞外基质蛋白的 OA 自身抗体定义了一个新的 OA 亚组，提示高浓度自身抗体的患者可能受益于免疫抑制治疗。
