Positional cloning of the Igl genes controlling rheumatoid factor production and allergic bronchitis in rats

Proc Natl Acad Sci U S A. 2008 Sep 16;105(37):14005-10. doi: 10.1073/pnas.0803956105. Epub 2008 Sep 8.


Rheumatoid factors (RF), autoantibodies that bind the Fc region of IgG, are one of the major diagnostic marker in rheumatoid arthritis (RA) but occur with lower frequency also in other infectious and inflammatory conditions. Through positional cloning of the previously described quantitative trait locus (QTL) Rf1 in congenic and advanced intercrossed rats, we identified the Ig lambda light chain locus as a locus that regulates the production of RF in rats. The congenic rats produce RF-Ig lambda and have significant higher levels of RF-IgG and RF-IgM in serum, while the DA rat has an impaired RF production and does not produces RF-Ig lambda. Thus, we could investigate the role of RF in pristane-induced arthritis (PIA) as well as ovalbumin-induced airway inflammation. We show that there was no difference in the development and severity of PIA between congenic and parental DA rats, suggesting that RF using lambda light chains have no impact on PIA. However, the RF producing congenic rats developed a more severe airway inflammation as indicated in the significantly increased number of eosinophils in bronchoalveolar lavage fluid as well as total IgE in serum. In addition, RF congenic rats had a significantly enhanced immune response toward OVA due to increased OVA-Igk but not OVA-Igl antibodies, suggesting a possible involvement of RF in the regulation of the humoral immune response.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles*
  • Animals
  • Animals, Congenic
  • Bronchitis / genetics
  • Bronchitis / immunology*
  • Bronchitis / metabolism*
  • Bronchitis / pathology
  • Cloning, Molecular
  • Genome / genetics
  • Hybridomas
  • Hypersensitivity / genetics
  • Hypersensitivity / immunology*
  • Hypersensitivity / metabolism
  • Hypersensitivity / pathology
  • Immunoglobulin lambda-Chains / genetics*
  • Immunoglobulin lambda-Chains / immunology*
  • Molecular Sequence Data
  • Rats
  • Rheumatoid Factor / genetics
  • Rheumatoid Factor / metabolism*


  • Immunoglobulin lambda-Chains
  • Rheumatoid Factor

Associated data

  • GENBANK/DQ394084
  • GENBANK/DQ394085
  • GENBANK/DQ394086
  • GENBANK/DQ394087
  • GENBANK/DQ394088
  • GENBANK/DQ394089
  • GENBANK/DQ394090
  • GENBANK/DQ394091
  • GENBANK/DQ394092
  • GENBANK/DQ394093