D. Asa et al., THE P-SELECTIN GLYCOPROTEIN LIGAND FUNCTIONS AS A COMMON HUMAN-LEUKOCYTE LIGAND FOR P-SELECTINS AND E-SELECTINS, The Journal of biological chemistry, 270(19), 1995, pp. 11662-11670
P- and E-selectins belong to a family of Ca2+-dependent lectins and fu
nction as receptors for myeloid leukocytes, We have described a panel
of monoclonal antibodies which recognize a sialoglycoprotein from huma
n neutrophils and HL-60 promyelocytic cells and inhibit adhesion of th
ese cells to P-selectin. In this study, we show that the E-selectin re
ceptor-globulin (E-selectin Rg) affinity chromatography can isolate sp
ecifically only one glycoprotein from [H-3] glucosamine-labeled HL-60
cells in a Ca2+-dependent manner. This protein has a molecular mass of
similar to 120 kDa under reducing conditions, which appears to be ide
ntical with the previously characterized glycoprotein ligand for P-sel
ectin, The molecule can be cross-depleted by and cross-bound to the E-
and P-selectin columns, The chromatographic profile of desialylated O
-linked carbohydrates from molecules purified by P- and E-selectin aff
inity chromatography are identical, Both have five structures at 12.8,
9.8, 6.3, 3.5, and 2.5 glucose units, PL5 monoclonal antibody to the
P-selectin sialoglycoprotein ligand, E-selectin Rg, and antiserum to P
-selectin glycoprotein ligand-1 (PSGL-1) all recognize the purified P-
selectin ligand on ligand blots and immunoblots. Furthermore, PL5 mono
clonal antibody blocks adhesion of HL-60 cells and human neutrophils t
o E-selectin Rg, Taken together, our results demonstrate that the P- a
nd E-selectin ligand defined in this study is PSGL-1 and suggest that
this molecule is an important leukocyte ligand for both P- and E-selec
tins.