B8.7 antigen is present on B-cell precursor acute lymphocytic leukemia.
Correlation with the low molecular weight B-cell growth factor
responsiveness of these cells
C Leprince, N Blumenfeld, G Flandrin, P Galanaud, F Sigaux and Y Richard
Inserm U 131, Clamari, France.
The purpose of this study was to analyze the expression of B8.7 antigen and
its implication in the low molecular weight B-Cell growth factor (LMW BCGF)
proliferative pathway at the early stages of the human B- cell
differentiation. After an overnight incubation in culture medium of B-cell
precursor acute lymphoblastic leukemias (ALL), we demonstrated the presence
of B8.7 antigen in 18 of 25 cases (72%). Such an incubation also induced a
significant increase in the LMW BCGF responsiveness of ALL cells (P less
than 0.03). In addition, we showed a significant correlation between B8.7
expression and the ability of pre-B ALL cells to respond to LMW BCGF. As
previously described for normal B cells, the anti-B8.7 monoclonal antibody
inhibited the LMW BCGF-dependent proliferation of pre-B ALL cells in a
dose-dependent manner. These data indicate that B8.7 antigen is expressed
and may be functionally related to the LMW BCGF pathway at the pre-B cell
stages of differentiation. These results also suggest that human B-cell
precursor ALL are not only phenotypically similar to their normal B
lymphocyte counterparts, but are also sensitive to the same
immunoregulatory cytokines that control normal cell growth.
Volume 75,
Issue 4,
pp. 963-971,
02/15/1990
Copyright © 1990 by The American Society of Hematology
