Complement activating rheumatoid factors in rheumatoid arthritis studied by haemolysis in gel: relation to antibody class and response to treatment with podophyllotoxin derivatives

Clin Exp Rheumatol. 1985 Jan-Mar;3(1):29-37.


Complement (C) activating rheumatoid factors (RF) were measured in 16 patients with rheumatoid arthritis (RA) by a simple haemolysis in gel (HIG) assay. IgM-RF, but not IgG-RF or IgA-RF, measured by an enzyme linked immuno-sorbent assay, were closely correlated with C activating RF (r = 0.86). In neither assay did the concentrations of RF appear to be directly related to C1 activation as expressed by serum concentrations of C1r-C1s-C1 inactivator complexes or of C4. In the sera, C1q binding substances, measured by C1q binding assay, were markedly correlated with C activating RF (r = 0.88), whereas C1q binding substances detected by the C1q deviation test were not. Treatment with podophyllotoxin derivatives for 6 months clearly reduced patients' RF concentrations. The decrease of IgG-RF, IgA-RF and IgM-RF was significantly more pronounced than that of the IgG, IgA and IgM concentrations, respectively.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antigen-Antibody Complex / analysis
  • Arthritis, Rheumatoid / blood*
  • Arthritis, Rheumatoid / drug therapy
  • Arthritis, Rheumatoid / physiopathology
  • Complement Activation*
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Hemolytic Plaque Technique*
  • Humans
  • Immunoglobulins / analysis
  • Immunoglobulins / classification*
  • Male
  • Middle Aged
  • Podophyllotoxin / analogs & derivatives*
  • Rheumatoid Factor / analysis
  • Rheumatoid Factor / physiology*


  • Antigen-Antibody Complex
  • Immunoglobulins
  • Rheumatoid Factor
  • Podophyllotoxin