Robbins D L, Wistar R
J Rheumatol. 1985 Jun;12(3):437-43.
Rheumatoid factor (RF) may play a role in sustaining the inflammatory events and tissue damage in rheumatoid arthritis (RA). However, many serum RF have greater specificity for rabbit IgG than for human IgG, thus raising questions about RF pathogenicity in RA. Serum RF also has specificity for human IgG subclasses 1, 2 and 4, but not for IgG3. The synovium is central to the pathology of RA; thus, RF made there may have greater pathogenicity than serum RF. We examined the specificity of 19S IgM RF in an RF plaque forming cell assay (RF-PFC) using RA synovial cells (RSC). We found that: (1) RSC produced greater numbers of RF-PFC/10(6) cells than did RA peripheral blood mononuclear cells (PBM); (2) RSC RF-PFC had greater specificity for human than for rabbit IgG compared to autologous serum RF; (3) RSC RF had significantly greater specificity for human IgG3 relative to autologous serum RF. In contrast, RSC RF and autologous serum RF had the same relative specificities for polyclonal human IgG, IgG1, IgG2, and IgG4. Thus, the specificity of much of the RF synthesized by RSC differed from serum RF. The potential pathogenic significance of these observations is discussed.
类风湿因子（RF）可能在类风湿关节炎（RA）的炎症持续及组织损伤过程中发挥作用。然而，许多血清RF对兔IgG的特异性高于对人IgG的特异性，因此引发了关于RF在RA中致病性的疑问。血清RF对人IgG亚类1、2和4也具有特异性，但对IgG3没有特异性。滑膜在RA的病理过程中起核心作用；因此，滑膜产生的RF可能比血清RF具有更强的致病性。我们使用类风湿关节炎滑膜细胞（RSC），通过RF斑块形成细胞试验（RF-PFC）检测了19S IgM RF的特异性。我们发现：（1）与类风湿关节炎外周血单个核细胞（PBM）相比，RSC产生的RF-PFC/10⁶细胞数量更多；（2）与自身血清RF相比，RSC RF-PFC对人IgG的特异性高于对兔IgG的特异性；（3）相对于自身血清RF，RSC RF对人IgG3的特异性显著更高。相比之下，RSC RF和自身血清RF对多克隆人IgG、IgG1、IgG2和IgG4具有相同的相对特异性。因此，RSC合成的许多RF的特异性与血清RF不同。本文讨论了这些观察结果的潜在致病意义。
