Skip to main content

Localisation of MHC Class II/HC gp-39 complexes in synovia of rheumatoid arthritis patients using complex-specific monoclonal antibodies

Objective

Recently HC gp-39 was identified as a candidate autoantigen in RA. The aim of this study is to generate and validate monoclonal antibodies (mAbs) to HLA DRαβ1*0401/HC gp-39263–275 complexes to further investigate the relevance of this antigen in RA.

Methods

Spleen cells from mice immunised with HLA DRαβ1*0401/HC gp-39263–275 complexes were selected and submitted to a B-cell culture and minielectrofusion procedures. The resulting set of mAbs were characterised for their specificity by ELISA and FACS. Functionally, they were tested for inhibition of HC gp-39263–275-specific DRαβ1*0401-restricted T-cell hybridomas. Finally, one of the mAbs was used for staining of specific complexes in RA synovium.

Results

We have generated a set of five mAbs to a combination epitope of the specific MHC/peptide complexes. FACS studies revealed that these mAbs recognize specific complexes on homozygous DRαβ1*0401-positive BLCL pulsed with HC gp-39263–275. The best mAb, 12A, was further characterized using a set of irrelevant DRαβ1*0401-binding peptides, and truncated/elongated versions of HC gp-39263–275 itself. The minimal epitope recognized in combination with DRαβ1*0401 was HC gp-39263–273. Peptides not encompassing HC gp-39263–273 were not recognized. Three out of five mAbs were able to inhibit (up to 90%) the response of HC gp-39263–275-specific DRαβ1*0401-restricted T-cell hybridomas to peptide-pulsed antigen-presenting cells or purified complexes. Moreover, mAb 12A localised and identified dendritic cells that present DRαβ1*0401/HC gp-39263–275 complexes in synovial tissue of DRαβ1*0401-positive RA patients.

Conclusions

These data indicate local presentation of the HC gp-39263–275 epitope in the inflamed target tissue by professional antigen-presenting cells and support a role of HC gp-39 in the local autoimmune response that leads to chronic inflammation and joint destruction.

Author information

Affiliations

Authors

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Baeten, D., Steenbakkers, P., Rovers, E. et al. Localisation of MHC Class II/HC gp-39 complexes in synovia of rheumatoid arthritis patients using complex-specific monoclonal antibodies. Arthritis Res Ther 5, 68 (2003). https://doi.org/10.1186/ar698

Download citation

Keywords

  • Rheumatoid Arthritis
  • Rheumatoid Arthritis Patient
  • Spleen Cell
  • Synovial Tissue
  • Joint Destruction