BINDING OF IMMUNOGLOBULINS AND IMMUNE-COMPLEXES TO CARTILAGE DERIVED EXTRACTS

  • 1 January 1983
    • journal article
    • research article
    • Vol. 54  (3) , 716-722
Abstract
Cartilage extracts with affinity for heat aggregated Ig were prepared from human articular and bovine nasal cartilage. These extracts, containing predominantly collagen, also bound both to immune complexes (IC) prepared in vitro and to Ig from sera of many patients with rheumatoid arthritis (RA). Cryoprecipitation of rheumatoid sera removed material reacting with the extract and density gradient fractionation of a positive serum showed correlation between binding to the extract and to C1q [complement component 1q]. The binding materials in rheumatoid sera were likely to be IC. Some assays which apparently demonstrate anti-collagen autoantibodies in fact measure IC. The findings also have implications for models of the pathogenesis of RA.