[Immunohistochemical study of lymphoid germinal centers--synovial tissues and lymph nodes of rheumatoid arthritis patients].

Rheumatoid arthritis (RA) is recognized as one of immune complex diseases and often have the lymph follicles with the germinal center (GC) in their synovialis. The author examined the GCs of 41 RA synovialis and 7 RA lymph nodes with massive lymphadenopathy during their clinical courses using the immunohistochemical technique according to Farr and Nakane. In GCs of both RA synovialis and RA lymph nodes, the presence of immunoglobulins (IgM, IgG), early complement components (C1q, C4, C3, C3c, C3d), and monoclonal antibodies (IgM-rheumatoid factor, C3b receptor) expressed themselves in lacy network pattern light-microscopically, and were proved on the surface of follicular dendritic cells (FDCs) and lymphocytes, and in the intercellular space electron-microscopically. Furthermore, the immunostaining for dendritic reticulum cell 1 was found in lacy network pattern light-microscopically and on the cell surface of FDC electron-microscopically. It is possible that both GCs may play an important role in systemic immune response.