Changes in 1,25-(OH)2D3 synthesis and its receptor expression in spleen cell subpopulations of mice infected with LPBM5 retrovirus.
This study examines the influence of chronic retroviral infection of mice with a LPBM5 virus mixture on the paracrine system involving immune cells and 1,25-(OH)2D3 in the spleen. Plasma ionized calcium, 25-(OH)D and 1,25-(OH)2D of infected mice were unchanged. In contrast, the specific binding of 1,25-(OH)2D3 to spleen cytosol and the number of monocyte/macrophages expressing 1,25-(OH)2D3 receptors (VDR) were markedly increased. The retroviral infection also influenced the local production of 1,25-(OH)2D3 in the spleen. It did not alter this production in monocyte/macrophages but increased that in isolated T cells. Isolated B cells in control mice did not produce 1,25-(OH)2D3, but they increased the ability of isolated T cells to produce this metabolite during coculture incubations. Infection altered this cell interaction as 1,25-(OH)2D3 production in infected T cells decreased when these cells were cocultured with infected B cells. Thus, chronic retroviral infection alters both the local vitamin D metabolism and VDR expression by immune cells in mice. These findings suggest close local interactions between 1,25-(OH)2D3 and immune system activation during retroviral infection.
Nguyen
T M
TM
CNRS, URA 583, Université Paris V, Hôpital Saint-Vincent de Paul, France.
Pavlovitch
J
J
Papiernik
M
M
Guillozo
H
H
Walrant-Debray
O
O
Pontoux
C
C
Garabedian
M
M
D000818:Animals; D002112:Calcifediol / Q000378:metabolism; D002117:Calcitriol / Q000378:metabolism*; D018920:Coculture Techniques; D005260:Female; D008214:Lymphocytes / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D009000:Monocytes / Q000378:metabolism; D016183:Murine Acquired Immunodeficiency Syndrome / Q000378:metabolism* / Q000473:pathology; D011956:Receptors, Cell Surface / Q000378:metabolism*; D013154:Spleen / Q000378:metabolism* / Q000473:pathology; D013601:T-Lymphocytes / Q000378:metabolism
D011956:Receptors, Cell Surface; D002117:Calcitriol; D002112:Calcifediol