Sulfation-independent L-selectin or E-selectin ligand (HCELL) and therapeutics thereof

摘要

An isolated and purified glycoprotein and functional analogues thereof are disclosed. The glycoproteins are characterized by being expressed on at least primitive hematopoietic cells, and being a ligand for L-selectin. The binding activity of the ligand of the present invention to L-selectin is not sulfation-dependent and it is neither inhibited by anti-CD34 antibodies nor by MECA-79 monoclonal antibody and the ligand is resistant to O-sialoglycoprotein endopeptidase activity. Further, the present invention provides a method of performing an overlay adherence assay by using isolated cells or cell lines as a substrate. The cells are prepared as the substrate for the assay using a cytocentrifuge with a modified sample chamber allowing placement of the cytocentrifuged cell pellet to any selected location on the slide as required by the shear conditions employed for any given assay.