Autoimmune reaction to type II collagen and cartilage degeneration in MRL/Mp- lpr/lpr mouse.
The early phase of cartilage degeneration was immunohistochemically examined in order to clarify the importance of autoimmune reaction against type II collagen in MRL/Mp- lpr/lpr (MRL/ l) mouse in an experimental model of rheumatoid arthritis (RA). Anti-type II collagen antibodies were detectable in 3-week-old mice and preceded the appearance of rheumatoid factors. Furthermore, mesenchymal cells and tartrate-resistant acid phosphatase-positive cells began to accumulate remarkably in the periphysis, a fibrochondro-osseous area in the bone marrow vicinity. The numbers of these cells increased with mice age, together with serum levels of anti-type II collagen antibodies. Immunostaining of the periphysis revealed expression of type II collagen, IgG, C3, Mac-3, MHC class II antigen Ia, and cathepsin-L. Osteoclast-like cells and macrophage infiltration into the lesion area were confirmed by transmission electron microscopy. The results indicate that cartilage degeneration in MRL/ l mouse may originate in the periphysis and progress via a pathway independent of synovial invasion.
Tanaka
Maki
M
Department of Orthopaedic Surgery, Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-ku, Tokyo 105-8461, Japan. maki-tnc@u01.gate01.com
Fujii
Katsuyuki
K
Tsuji
Michiko
M
Sawai
Takashi
T
D000818:Animals; D001172:Arthritis, Rheumatoid / Q000276:immunology; D001323:Autoantibodies / Q000276:immunology; D001327:Autoimmune Diseases / Q000150:complications / Q000276:immunology*; D002357:Cartilage Diseases / Q000150:complications / Q000276:immunology*; D024043:Collagen Type II / Q000276:immunology*; D005260:Female; D051379:Mice; D019463:Mice, Inbred MRL lpr; D023421:Models, Animal
D001323:Autoantibodies; D024043:Collagen Type II