Details

Autor(en) / Beteiligte

• Chen, Sheng
• Sims, Gary P
• Chen, Xiao Xiang
• Gu, Yue Ying
• Chen, Shunle
• Lipsky, Peter E

Titel

Modulatory Effects of 1,25-Dihydroxyvitamin D sub(3) on Human B Cell Differentiation

Ist Teil von

• Journal of Immunology, 2007-08, Vol.179 (3), p.1634-1647

Erscheinungsjahr

2007

Link zum Volltext

Quelle

Wiley Online Library

Beschreibungen/Notizen

• 1,25-Dihydroxyvitamin D sub(3) (1,25(OH) sub(2)D sub(3)) can modulate immune responses, but whether it directly affects B cell function is unknown. Patients with systemic lupus erythematosus, especially those with antinuclear Abs and increased disease activity, had decreased 1,25(OH) sub(2)D sub(3) levels, suggesting that vitamin D might play a role in regulating autoantibody production. To address this, we examined the effects of 1,25(OH) sub(2)D sub(3) on B cell responses and found that it inhibited the ongoing proliferation of activated B cells and induced their apoptosis, whereas initial cell division was unimpeded. The generation of plasma cells and postswitch memory B cells was significantly inhibited by 1,25(OH) sub(2)D sub(3), although the up-regulation of genetic programs involved in B cell differentiation was only modestly affected. B cells expressed mRNAs for proteins involved in vitamin D activity, including 1 alpha -hydroxylase, 24-hydroxylase, and the vitamin D receptor, each of which was regulated by 1,25(OH) sub(2)D sub(3) and/or activation. Importantly, 1,25(OH) sub(2)D sub(3) up-regulated the expression of p27, but not of p18 and p21, which may be important in regulating the proliferation of activated B cells and their subsequent differentiation. These results indicate that 1,25(OH) sub(2)D sub(3) may play an important role in the maintenance of B cell homeostasis and that the correction of vitamin D deficiency may be useful in the treatment of B cell-mediated autoimmune disorders.