Rc. Briggs et al., REGULATION AND SPECIFICITY OF MNDA EXPRESSION IN MONOCYTES, MACROPHAGES, AND LEUKEMIA-B LYMPHOMA CELL-LINES, Journal of cellular biochemistry, 56(4), 1994, pp. 559-567
The expression of the human myeloid cell nuclear differentiation antig
en (MNDA) was observed specifically in cells of the granulocyte-macrop
hage lineage in our earlier reports. The specificity of MNDA expressio
n for cells in the granulocyte-macrophage lineage was reexamined in ce
ll lines established from patients with Philadelphia chromosome-positi
ve chronic myeloid leukemia. Cell lines that expressed MNDA exhibited
myeloid cell features and granulocyte or monocyte differentiation coul
d be induced in vitro, while cell lines exhibiting properties of very
early stage cells or multipotential cells did not express MNDA. Cells
originating from cases of Burkitt's lymphoma were negative. By contras
t, three lymphoblastoid cell lines (immortalized in vitro with Epstein
-Barr virus) were weakly positive and MN DA was up-regulated by interf
eron-alpha (IFN-alpha) treatment. As we reported previously, MNDA mRNA
level in adherent monocytes is elevated by IFN-alpha; in this study,
we further assessed MNDA expression in in vitro monocyte-derived macro
phages. Three additional agents (endotoxin, phytohemagglutinin, and ph
orbol ester) and other conditions that affect function, cytokine produ
ction, differentiation, and/or growth of monocytes were examined for t
heir ability to alter MNDA expression. The results varied with the age
nt, cell type, and stage of differentiation. Changes in MNDA expressio
n occurred slowly (hours to days), suggesting that MNDA could mediate
changes realized over a long period. The results also reveal a discord
ance in certain MNDA positive cells between steady-state levels or cha
nges in levels of protein and mRNA indicating that the regulation of M
NDA expression occurs at more than one point. Changes in MNDA expressi
on are consistent with a role in opposing macrophage differentiation a
nd activation of monocytes/macrophages. (C) 1994 Wiley-Liss, Inc.