Autoimmunity to cartilage link protein in patients with rheumatoid arthritis and ankylosing spondylitis.
OBJECTIVE
To determine whether patients with rheumatoid arthritis (RA) and ankylosing spondylitis (AS) express cellular immunity to cartilage link protein (LP).


METHODS
LP was purified from human fetal epiphyseal and bovine adult nasal cartilage. It was used in proliferation assays with the peripheral blood lymphocytes (PBL) isolated from 83 patients with RA, 21 patients with AS, and 30 healthy controls.


RESULTS
Patients with RA (34%) and AS (71%) expressed a significantly higher prevalence of cellular immune responses to human LP compared with the healthy control group (13%). Such significant differences were not observed for bovine LP. Half the patients with RA responding to LP exhibited cellular immunity to both human and bovine protein. In the AS group, PBL from a majority of responders to LP recognized only human LP.


CONCLUSIONS
These data suggest that LP is a potential autoantigen in the development of RA and AS and that cellular immune reactivity to common and distinct LP epitopes in patients with RA and AS may play a role in the pathogenesis of these diseases.
Guerassimov
A
A
Joint Diseases Laboratory, Shriners Hospital for Children, McGill University, Montreal, Quebec, Canada. aguerassimov@shriners.mcgill.CA
Zhang
Y
Y
Banerjee
S
S
Cartman
A
A
Webber
C
C
Esdaile
J
J
Fitzcharles
M A
MA
Poole
A R
AR
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001172:Arthritis, Rheumatoid / Q000150:complications / Q000276:immunology*; D001324:Autoantigens / Q000276:immunology; D015551:Autoimmunity; D002417:Cattle; D016326:Extracellular Matrix Proteins; D005260:Female; D006801:Humans; D007111:Immunity, Cellular; D008297:Male; D008875:Middle Aged; D011487:Protein Conformation; D011506:Proteins / Q000276:immunology*; D011509:Proteoglycans / Q000276:immunology; D013167:Spondylitis, Ankylosing / Q000150:complications / Q000276:immunology*; D000099249:Proteoglycan Link Protein
D001324:Autoantigens; D016326:Extracellular Matrix Proteins; D011506:Proteins; D011509:Proteoglycans; D000099249:Proteoglycan Link Protein