Anti-MBL autoantibodies in patients with rheumatoid arthritis: prevalence and clinical significance

J Autoimmun. 2006 Sep;27(2):125-33. doi: 10.1016/j.jaut.2006.07.002. Epub 2006 Aug 10.


Occurrence of autoantibodies in patients' sera is the characteristic feature of autoimmune disorders. We assessed the presence of anti-mannose binding lectin (MBL) autoantibodies in the sera of 107 rheumatoid arthritis (RA) patients and 121 control subjects by enzyme immunoassay. Elevated levels of anti-MBL autoantibodies in the sera of RA patients (P<0.0001) was detected for the first time. The ratios of anti-MBL positive in RA patients and controls were respectively 60.7% and 1.65%. Experiments were then designed to understand the functional relevance of these autoantibodies. An inverse correlation of anti-MBL autoantibodies with serum MBL levels (P=0.001) and MBL complex activity (P=0.02) was observed without genetic association between MBL polymorphisms and anti-MBL autoantibody secretion. A significant increase (P=0.038) in the level of anti-MBL autoantibodies was observed in 23 synovial fluid samples in comparison to the serum samples. Moreover, the anti-MBL autoantibodies were found to be more often present in the sera of RA patients (60.75% sensitivity, 98.35% specificity and 0.913 area under the ROC curve) in comparison to the IgM and IgG isotypes of rheumatoid factors (RF). Anti-MBL autoantibodies were still positive in 25.23% RA patients when both the RF isotypes were negative. Also, in RA patients, at all stages of disease activity and joint deformity, anti-MBL autoantibodies were more often present than both the RF isotypes. Therefore, the significant presence of anti-MBL autoantibodies enunciates that anti-MBL autoantibodies might have a diagnostic value; however, more studies are needed to confirm the role of anti-MBL autoantibodies in the diagnosis of rheumatoid arthritis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Arthritis, Rheumatoid / blood*
  • Arthritis, Rheumatoid / diagnosis*
  • Arthritis, Rheumatoid / immunology
  • Autoantibodies / blood*
  • Autoantigens / immunology
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Humans
  • Immunoglobulin Isotypes / blood
  • Immunoglobulin Isotypes / immunology
  • Male
  • Mannose-Binding Lectin / blood
  • Mannose-Binding Lectin / immunology*
  • Prevalence
  • ROC Curve
  • Rheumatoid Factor / blood
  • Rheumatoid Factor / immunology
  • Sensitivity and Specificity
  • Synovial Fluid / chemistry
  • Synovial Fluid / immunology


  • Autoantibodies
  • Autoantigens
  • Immunoglobulin Isotypes
  • Mannose-Binding Lectin
  • Rheumatoid Factor