Detection of insulin-like growth factor I and II in synovial tissue specimens of patients with rheumatoid arthritis and osteoarthritis by in situ hybridization.
OBJECTIVE
To study the expression of insulin-like growth factor I and II (IGF I and II) in synovial tissue specimen of patients with rheumatoid arthritis (RA) and osteoarthritis (OA).


METHODS
Synovial tissue sections were examined for the expression of IGF I and II by in situ hybridization using digoxigenin labeled antisense and sense RNA probes.


RESULTS
The antisense probe of IGF I reacted with all specimens. IGF II mRNA was expressed in 7/7 RA and 4/5 OA tissues. Cells of the synovial lining and subsynovial layer bound both antisense probes, whereas inflammatory infiltrates of RA tissues were labeled rarely.


CONCLUSIONS
The significant number of cells in the synovium that express IGF I and II mRNA suggests a role of IGF in repair mechanisms of articular cartilage in response to injury and effects on fibroblast growth within the synovium.
Keyszer
G M
GM
University of Alabama, Department of Medicine, Birmingham 35294-0006, USA.
Heer
A H
AH
Kriegsmann
J
J
Geiler
T
T
Keysser
C
C
Gay
R E
RE
Gay
S
S
D001172:Arthritis, Rheumatoid / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D017403:In Situ Hybridization; D007334:Insulin-Like Growth Factor I / Q000235:genetics / Q000378:metabolism*; D007335:Insulin-Like Growth Factor II / Q000235:genetics / Q000378:metabolism*; D010003:Osteoarthritis / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D013583:Synovial Membrane / Q000378:metabolism* / Q000473:pathology
D012333:RNA, Messenger; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II