Y. Toritsuka et al., OSTEOCLASTOGENESIS IN ILIAC BONE-MARROW OF PATIENTS WITH RHEUMATOID-ARTHRITIS, Journal of rheumatology, 24(9), 1997, pp. 1690-1696
Objective. To investigate osteoclastogenesis in bone marrow cells from
patients with various pathogenic backgrounds known to induce osteopor
osis, to identify specific factors that may cause generalized osteopor
osis in patients with rheumatoid arthritis (RA). Methods. Bone marrow
blood was obtained from 59 women, 36 with RA and 23 without RA. Patien
ts with RA were classified as severe (26) and mild RA (10: 5 patients
with and 5 without corticosteroid therapy). The non-RA subjects were d
ivided into 3 groups, premenopausal (7), menopausal (8), and elderly (
8), As a marker of bone resorption, the pyridinoline crosslinked telop
eptide domain of type I collagen (ICTP) concentration in the bone marr
ow supernatant was measured by radioimmunoassay. The bone marrow cells
were cultured 14 days in the presence or absence of autologous bone m
arrow supernatant; then the number of tartrate resistant acid phosphat
ase positive multinucleated cells (TRAP positive MNC) was counted as a
n indicator of osteoclastogenesis. Results. ICTP concentration of the
bone marrow supernatant and the number of TRAP positive MNC showed rem
arkable enhancement in some patients with severe RA, but these feature
s were not observed in the 3 control groups. Conclusion. Increased bon
e resorption and enhanced osteoclastogenesis were specifically observe
d in the iliac bone marrow of patients with RA, especially those with
severe RA. These phenomena can be considered to accompany generalized
osteoporosis in RA.