Human rheumatoid synovial cells (HRSC) in culture express TGF-beta receptors and are growth stimulated by the factor.
TGF-beta (5 ng/ml) increased the proliferation rate of HRSC by 30% after 96 h of treatment. One type of TGF-beta binding system, with apparent Kd of 953 pM and a number of 29,400 receptors/cell, was detected by Scatchard analysis of [125I]-TGF-beta binding. However, crosslinking experiments and SDS-PAGE separation showed five TGF-beta binding proteins: 50, 70, 110, 140 and 400 kDa. We may suggest that the affinities of these receptors are too close to be revealed by Scatchard plot. All together, the data suggest that TGF-beta plays a role in the hyperplasia of RA synovial tissue.
Laboratoire de Biochimie du Tissu Conjonctif, C.H.U. Niv. 3, Caen, France.
S
S
Pronost
F
F
Rédini
D
D
Vivien
P
P
Galéra
J P
JP
Pujol
D001172:Arthritis, Rheumatoid / Q000378:metabolism*; D001345:Autoradiography; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D003432:Cross-Linking Reagents / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D007457:Iodine Radioisotopes; D007700:Kinetics; D011956:Receptors, Cell Surface / Q000096:biosynthesis*; D018125:Receptors, Transforming Growth Factor beta; D013268:Stimulation, Chemical; D013583:Synovial Membrane / Q000166:cytology / Q000378:metabolism*; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
D003432:Cross-Linking Reagents; D007457:Iodine Radioisotopes; D011956:Receptors, Cell Surface; D018125:Receptors, Transforming Growth Factor beta; D016212:Transforming Growth Factor beta