Relationship between IgG2b-inducing activity in rheumatoid arthritis synovial fluid and other well-known cytokines and inflammatory mediators.
In the present study, we sought to identify the T cell-replacing factor which selectively induces IgG2b antibody formation in lipopolysaccharide-activated mouse spleen cells in vitro and in vivo, and which is present in the synovial fluid (SF) of rheumatoid arthritis (RA) patients. The protein A plaque assay was used to measure IgM, IgG1, IgG2b, and IgG3 plaque-forming cells. An enzyme-linked immunosorbent assay was used to measure interleukin-6 (IL-6) levels in RA SF. We found that IgG2b induction by RA SF is not caused by IL-6, IL-1, or any other inflammatory cytokines or mediators, such as transforming growth factor beta, platelet-derived growth factor, nerve growth factor, fibroblast growth factor, epidermal growth factor, elastase, collagenase, and phospholipase A2. IgG2b-inducing factor in RA SF has unique biological properties compared with those of the interleukins and inflammatory mediators known to be present in RA SF.
Abedi-Valugerdi
M
M
Department of Immunology, Arrhenius Laboratories for Natural Sciences, University of Stockholm, Sweden.
Ridderstad
A
A
Ström
H
H
Möller
E
E
D000888:Antibodies, Anti-Idiotypic / Q000032:analysis*; D001172:Arthritis, Rheumatoid / Q000276:immunology*; D016207:Cytokines / Q000502:physiology*; D006133:Growth Substances / Q000502:physiology*; D006801:Humans; D007074:Immunoglobulin G / Q000096:biosynthesis*; D007075:Immunoglobulin M / Q000032:analysis; D007375:Interleukin-1 / Q000276:immunology; D015850:Interleukin-6 / Q000276:immunology; D013582:Synovial Fluid / Q000201:enzymology / Q000276:immunology*
D000888:Antibodies, Anti-Idiotypic; D016207:Cytokines; D006133:Growth Substances; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007375:Interleukin-1; D015850:Interleukin-6