title: P-selectin glycoprotein ligand-1 is broadly expressed in cells of myeloid, lymphoid, and dendritic lineage and in some nonhematopoietic cells.
abstract: P-selectin glycoprotein ligand-1 (PSGL-1) is a muclin-like glycoportein ligand for P- and E-selectin on myeloid cells and a subset of lymphocytes. We used flow cytometry and immunohistochemistry to examine expression of PSGL-1 on minor leukocyte populations, differentiating hematopoletic cells, and nonhematopoietic tissues using two monoclonal antibodies to distinct protein epitopes on PSGL-1. In the bone marrow, PSGL-1 was expressed on myeloid cells from the myeloblast stage to the segmented neutrophil, but was not detected on erythroblasts or megakaryocytes. All types of circulating myeloid cells expressed PSGL-1, and PSGL-1 was retained after extravasation of myetoid cells into tissues. PSGL-1 was also expressed on circulating dendritic cells, monocyte-derived dendritic cells, dendritic cells in lymphoid tissues and epidermis, and follicular dendritic cells. All types of lymphoid cells examined expressed PSGK-1, including immature and mature thymocytes, naive and memory T cells, gamma/delta T cells, netural killer cells, B cells and CD34+ progenitor cells. However, PSGL-1 levels were substantially lower on tonsillar lymphocytes than on circulating lymphocytes, suggesting that PSGL-1 expression is down regulated during or after entry of lymphocytes into secondary lymphoid tissue. Although PSGL-1 antigen was detected primarily on hamatopoietic cells, it was also present on time epithelium of the fallopian tube. Furthermore, PSGL-1 antigen gen was detected sporadically on microvascular endothelium in some pathologic tissues. This suggests that PSGL-1 may have functions other than mediating leukocyte adhersion.
authors.affiliation: Department of Pathology, W.K. Warren Medical Research Institute, University of Oklahoma Health Sciences Center, Oklahoma City 73104-5073, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Laszik
authors.forename: P J
authors.initials: PJ
authors.lastname: Jansen
authors.forename: R D
authors.initials: RD
authors.lastname: Cummings
authors.forename: T F
authors.initials: TF
authors.lastname: Tedder
authors.forename: R P
authors.initials: RP
authors.lastname: McEver
authors.forename: K L
authors.initials: KL
authors.lastname: Moore
mesh_terms: D001853:Bone Marrow / Q000378:metabolism; D001854:Bone Marrow Cells; D019070:Cell Lineage; D002469:Cell Separation; D003713:Dendritic Cells / Q000378:metabolism*; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D006412:Hematopoietic Stem Cells / Q000378:metabolism*; D006801:Humans; D007962:Leukocytes / Q000378:metabolism*; D008214:Lymphocytes / Q000378:metabolism*; D008221:Lymphoid Tissue / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000235:genetics; D009928:Organ Specificity; D019007:P-Selectin / Q000378:metabolism
chemical_list: D008562:Membrane Glycoproteins; D019007:P-Selectin; C084882:P-selectin ligand protein