Regulation of expression of a human intercellular adhesion molecule
(ICAM-1) during lymphohematopoietic differentiation
AW Boyd, SM Dunn, JV Fecondo, JG Culvenor, U Duhrsen, GF Burns and SO Wawryk
Walter and Eliza Hall Institute of Medical Research, Royal Melbourne
Hospital, Victoria, Australia.
The intercellular adhesion molecule (ICAM-1) is a cell-surface molecule
which binds to leukocyte function antigen-1 (LFA-1) and regulates both
leukocyte adhesion to endothelial cells and immune functions requiring
cell-cell contact. Membrane expression of ICAM-1 is highly regulated on all
hematopoietic lineages. Cell membrane antigen is significantly expressed on
a small subset of bone marrow (BM) progenitors but is weak or absent on all
cell lineages once they enter the circulation. However, strong expression
on tissue macrophages and germinal center B cells suggested that activated
cells may show upregulated expression. When B cells, T cells, macrophages,
or granulocytes were activated in vitro by suitable mitogens, ICAM-1
expression was induced in all cases. Parallel studies of hematopoietic
tumors demonstrated a heterogeneity of expression which correlated with
expression on their normal cellular counterparts. In particular, a striking
correlation between expression on B-cell tumors and corresponding stages of
B-cell differentiation was noted. The widely varying expression of ICAM-1
contrasts with LFA-1 which, while variable, is nevertheless significantly
positive at all stages of differentiation. This suggests that the major
regulation of homotypic adhesion mediated by the LFA-1/ICAM-1 linkage
occurs through control of ICAM-1 expression. In keeping with this notion,
ICAM-1 expression was also correlated with the "adhesiveness" of B-lymphoid
tumors. Large solitary lymphoma masses showed intense expression of ICAM-1.
Conversely, chronic lymphocytic leukemia (CLL) cells and lymphoma cells
from tumors exhibiting diffuse, widespread lymph node disease showed weak
expression. These observations are discussed in relation to the role of
ICAM-1 in regulation of lymphoid recirculation and the biology of lymphoid
tumors.
Volume 73,
Issue 7,
pp. 1896-1903,
05/15/1989
Copyright © 1989 by The American Society of Hematology
