Use of a monoclonal antibody (GA3) to demonstrate lineage restricted O-
glycosylation on leukosialin during terminal erythroid differentiation
A Bettaieb, F Farace, MT Mitjavila, Z Mishal, MC Dokhelar, T Tursz, J Breton- Gorius, W Vainchenker and N Kieffer
INSERM U 91, Hopital Henri Mondor, Creteil, France.
A murine monoclonal antibody (GA3) obtained by immunizing mice with cells
of the human erythroleukemic cell line K562 is shown to define a 105
kilodalton (kd) membrane antigen on K562 cells that is restricted within
the hematopoietic system to the erythroid lineage and to a minor population
of CD3, CD4 positive T lymphocytes. Cocapping studies and
immunoprecipitation experiments performed with GA3 and L10, an anti-
sialophorin monoclonal antibody reacting with leukosialin (Gp 105) on K562
cells, demonstrate that the antigen detected by GA3 on K562 cells is
identical to leukosialin. Neuraminidase treatment but not tunicamycin
treatment of K562 cells abolishes the expression of the GA3- epitope
without affecting the L10-epitope thus providing evidence that terminal
sialic acid present on O-linked oligosaccharide chains on Gp 105 is
essential for the expression of the GA3-epitope. Further analysis by flow
cytometry and immune panning experiments performed on bone marrow cells
with GA3 or L10 demonstrate that, in contrast to L10, which reacts with all
types of hematopoietic progenitors, the epitope recognized by GA3 is
restricted to the erythroid lineage, and appears during erythroid
differentiation before glycophorin A on the earliest morphologically
recognizable erythroid precursor, the proerythroblast. Our results
therefore suggest that O-linked oligosaccharides on leukosialin express
lineage restricted and even maturation restricted antigenic structures that
might serve as cell lineage specific markers.
Volume 71,
Issue 5,
pp. 1226-1233,
05/01/1988
Copyright © 1988 by The American Society of Hematology
