Differentiation of mouse myeloid leukemia cells induced by 1 alpha,25-dihydroxyvitamin D3.

TLDR

1α,25‑D3 induces differentiation of mouse myeloid leukemia cells into macrophages in vitro. The study found that 1α,25‑D3 triggers macrophage differentiation at concentrations as low as 0.12 nM, with 12 nM producing effects comparable to 1 µM dexamethasone, phagocytic activity appearing within 24 h followed by lysozyme and locomotive activity, while related metabolites show weaker activity, suggesting a role for 1α,25‑D3 in bone marrow cell differentiation.

Abstract

Mouse myeloid leukemia cells can be induced to differentiate into macrophages in vitro by 1 alpha,25-dihydroxyvitamin D3, the active form of vitamin D3. The minimal concentration of 1 alpha,25-dihydroxyvitamin D3 to induce the cell differentiation was 0.12 nM. The degree of cell differentiation in various markers induced by 12 nM 1 alpha,25-dihydroxyvitamin D3 was nearly equivalent to that induced by 1 microM dexamethasone, the most potent known stimulator. Among several markers of the differentiation by 1 alpha,25-dihydroxyvitamin D3, phagocytic activity was induced within 24 hr, and this was followed by induction of lysozyme and locomotive activities. Similar changes were also induced by 0.01-1 microM 1 alpha-hydroxyvitamin D3. 25-Hydroxyvitamin D3 and 24R,25-dihydroxyvitamin D3 showed only weak inducing activity. These results suggest the possibility that, in addition to its wellknown biological activities in enhancing intestinal calcium transport and bone mineral mobilization, 1 alpha, 25-dihydroxyvitamin D3 is involved in the differentiation of bone marrow cells.