Destructive effects of murine arthritogenic antibodies to type II collagen on cartilage explants in vitro

• Published in: Arthritis research & therapy Vol. 7; no. 5; pp. R927 - R937
• Main Authors: Crombie, Duncan E, Turer, Muhammed, Zuasti, Beltzane Biurrun, Wood, Bayden, McNaughton, Don, Nandakumar, Kutty Selva, Holmdahl, Rikard, Van Damme, Marie-Paule, Rowley, Merrill J
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 2005; BioMed Central
• Subjects: Animals; Antibodies; Antibodies, Monoclonal - immunology; Antigen-Antibody Reactions; Arthritis; Arthritis, Experimental - immunology; Articular/immunology; Autoantibodies - immunology; Cartilage; Cartilage, Articular - immunology; Cattle; Clinical Medicine; Collagen Type II - immunology; Coloring Agents - analysis; Epitopes - immunology; Experimental/immunology; Extracellular Matrix - immunology; Extracellular Matrix - ultrastructure; Extracellular Matrix/immunology/ultrastructure; Fourier Transform Infrared; Immunoglobulin Fab Fragments - immunology; Immunoglobulin Fc Fragments - immunology; Klinisk medicin; Medical and Health Sciences; Medicin och hälsovetenskap; Mice; Monoclonal/immunology; Organ Culture Techniques; Protein Denaturation; Proteoglycans - metabolism; Reumatologi och inflammation; Rheumatology and Autoimmunity; Spectroscopy; Spectroscopy, Fourier Transform Infrared; Tolonium Chloride - analysis
• ISSN: 1478-6354; 1478-6362; 1478-6362
• DOI: 10.1186/ar1766

Certain monoclonal antibodies (mAbs) to type II collagen (CII) induce arthritis in vivo after passive transfer and have adverse effects on chondrocyte cultures and inhibit self assembly of collagen fibrils in vitro. We have examined whether such mAbs have detrimental effects on pre-existing cartilage. Bovine cartilage explants were cultured over 21 days in the presence of two arthritogenic mAbs to CII (CIIC1 or M2139), a non-arthritogenic mAb to CII (CIIF4) or a control mAb (GAD6). Penetration of cartilage by mAb was determined by immunofluorescence on frozen sections and correlated with changes to the extracellular matrix and chondrocytes by morphometric analysis of sections stained with toluidine blue. The effects of mAbs on matrix components were examined by Fourier transform infrared microspectroscopy (FTIRM). A possible role of Fc-binding was investigated using F(ab)2 from CIIC1. All three mAbs to CII penetrated the cartilage explants and CIIC1 and M2139, but not CIIF4, had adverse effects that included proteoglycan loss correlating with mAb penetration, the later development in cultures of an abnormal superficial cellular layer, and an increased proportion of empty chondrons. FTIRM showed depletion and denaturation of CII at the explant surface in the presence of CIIC1 or M2139, which paralleled proteoglycan loss. The effects of F(ab)2 were greater than those of intact CIIC1. Our results indicate that mAbs to CII can adversely affect preformed cartilage, and that the specific epitope on CII recognised by the mAb determines both arthritogenicity in vivo and adverse effects in vitro. We conclude that antibodies to CII can have pathogenic effects that are independent of inflammatory mediators or Fc-binding.