Objective: To study the expression of collagenase 3 (matrix metalloproteinase 13 [MMP-13]) and collagenase 1 (MMP-1) in synovial fibroblasts from patients with rheumatoid arthritis (RA) when cultured within 3-dimensional collagen gels or coimplanted with normal cartilage in immunodeficient NOD/SCID mice.
Methods: Messenger RNA (mRNA) and protein expression of collagenase 3 and collagenase 1 were characterized in synovial and skin fibroblasts by Northern blot and Western blot analysis. The mRNA expression of both collagenases in cell-cartilage implants in NOD/SCID mice was investigated by in situ hybridization in combination with immunohistochemistry of human fibroblasts.