A hematopoietic organ-specific 49-kD nuclear antigen: predominance in
immature normal and tumor granulocytes and detection in hematopoietic
precursor cells
BC Lee, Y Shav-Tal, A Peled, Y Gothelf, W Jiang, J Toledo, RE Ploemacher, N Haran-Ghera and D Zipori
Department of Molecular Cell Biology, the Weizmann Institute of Science,
Rehovot, Israel.
A 49-kD protein was specifically detected in hematopoietic organs by
Western blotting with a novel mouse monoclonal antibody (B92) raised
against stromal cells. The protein was found in the immunizing cells using
a sensitive method. However, its detection in the bone marrow by the B92
antibody seemed to stem from the abundance of p49 in immature cells of the
myeloid lineage. Study of the bone marrow following in vivo irradiation or
5-fluorouracil (5-FU) treatment, in vitro culture with
differentiation-inducing factors and long-term culture, and cell sorting
all pointed in the same direction: the protein was found in early myeloid
cells and in hematopoietic precursor cells. These results were in
accordance with the specific presence of p49 in primary radiation-induced
myeloid leukemia and its absence in spontaneous B lymphoma.
Immunofluorescent staining using B92 antibody detected a nuclear antigen
forming a dotted pattern in early myeloid cells and day 12 colony-forming
units-spleen (CFU-S). Nuclear localization of p49 was further demonstrated
by subcellular fractionation followed by Western blotting. We thus
identified a nuclear protein that within the hematopoietic population is
detected in hematopoietic precursor cells, predominates in early myeloid
cells, and is reduced following differentiation. These properties imply
that p49 might be involved in the regulation of hematopoietic cell growth
or differentiation.
Volume 87,
Issue 6,
pp. 2283-2291,
03/15/1996
Copyright © 1996 by The American Society of Hematology
