International Journal of Cell Cloning, Vol 3, 65-80, Copyright © 1985 by AlphaMed Press
1,25-Dihydroxyvitamin D3 and the regulation of the differentiation and function of macrophages and granulocytes
E Shezen and R Goldman
1,25-Dihydroxyvitamin D3 (1,25(OH)2D3) exerts a differential inhibitory
effect on the formation of granulocyte, granulocyte/macrophage, and
macrophage colonies grown from mouse bone marrow precursor cells; 50%
inhibition was attained at 1.1, 2.3, and 23 nM 1,25(OH)2D3, respectively.
The inhibition of colony formation, as well as phagocyte proliferation in
liquid cultures, requires the presence of 1,25(OH)2D3 in the early stages
of culture (up to 72 h after culture initiation). 1,25(OH)2D3 induces a
dose- and time-dependent augmentation of the phagocytic capability of
mononuclear phagocytes (up to 100%) towards both heat-killed yeast cells
and IgG-coated sheep red blood cells. The augmentation of the phagocytic
capability of the mononuclear phagocytes depends critically on when
1,25(OH)2D3 is added. It is effective when added up to 72 h after culture
initiation, while at later stages (greater than or equal to 96 h) the cells
are no longer induced to express enhanced phagocytic capability. We suggest
that these phenomena may be relevant to hemopoietic processes.
