¿Son las células T reguladoras de la activación del metabolismo óseo en niños..

«¿Son las células T reguladoras de la activación del metabolismo óseo en niños con la enfermedad de Crohn?»

Francisco A. Sylvester MD, , Patricia M. Davis, Nancy Wyzga, Jeffrey S. Hyams and Trudy Lerer

From the Connecticut Children’s Medical Center, Hartford, Connecticut; Saint Francis Hospital & Medical Center, Hartford, Connecticut; and University of Connecticut School of Medicine, Farmington, Connecticut

Objectives To test the hypothesis that circulating activated T cells may release cytokines that decrease bone turnover in children with Crohn disease.

Study design Newly diagnosed Crohn disease and healthy controls of similar age were compared for bone age, bone mineral content and density, markers of bone remodeling, and serum concentration and in vitro T-cell production of receptor activator of nuclear factor κB ligand (RANKL), interferon (INF)-γ, and osteoprotegerin (OPG).

Results Newly diagnosed children with Crohn disease (n = 23) had similar bone mineral density (BMD) z-scores and body mass index as the controls (n = 40). Biochemical markers of bone remodeling indicated a state of low bone turnover in the Crohn disease patients compared with controls. Serum OPG (pmol/L; mean ± SD, median) was higher (4.24 ± 1.74, 3.98 vs 3.38 ± 0.83, 3.41; P < .05), and serum RANKL (pmol/L) was lower in the Crohn disease patients (0.50 ± 0.86, 0.28 vs 1.02 ± 1.63, 0.49; P < .01), consistent with decreased bone resorption. Activated T cells from Crohn disease patients produced a higher concentration of INF-γ (ng/μg protein) than those from controls (20.03 ± 26.39, 8.70 vs 9.76 ± 14.10, 6.17; P < .05).

Conclusions The newly diagnosed children with Crohn disease exhibited reduced bone remodeling, possibly due to T-cell INF-γ and OPG.

The Journal of Pediatrics Volume 148, Issue 4 , April 2006, Pages 461-466.