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.

Caveolar Endocytosis Is Required for Human PSGL-1-Mediated Enterovirus 71 Infection

“…In contrast to the ubiquitous expression of SCARB2 in somatic cells, PSGL-1 is restrictedly expressed in myeloid, lymphoid, and dendritic cells and serves as a common ligand for P-, L-, or Eselectin in platelets, leukocytes, or endothelium cells. It plays a role in leukocyte and inflammatory cell infiltration in inflammatory tissues (14,15). P-selectin glycoprotein ligand-1 has been identified as one of the receptors to which EV71 binds when it infects myeloid, lymphoid, and dendritic cells.…”

“…Previous studies have demonstrated that hSCARB2 expression can enable normally unsusceptible cell lines to support EV71 propagation and develop cytopathic effects (8). P-selectin glycoprotein ligand-1 is a sialomucin membrane protein restrictively expressed in leukocytes, dendritic cells, tissue macrophages (those in the liver, lung, bowel, and Langerhans cells in the skin), and progenitor myeloid cells (14). It plays a role in the binding of leukocytes to endothelial cells and platelets and in the early stages of inflammation (14,15).…”

“…P-selectin glycoprotein ligand-1 is a sialomucin membrane protein restrictively expressed in leukocytes, dendritic cells, tissue macrophages (those in the liver, lung, bowel, and Langerhans cells in the skin), and progenitor myeloid cells (14). It plays a role in the binding of leukocytes to endothelial cells and platelets and in the early stages of inflammation (14,15). The expression of human PSGL-1 in normally unsusceptible cell lines can also facilitate EV71 infection, leading to the development of cytopathic effects (9,16).…”

Developments towards antiviral therapies against enterovirus 71

“…SCARB2 is a type III double-transmembrane protein primarily located in endosomes, although surface expression of SCARB2 has also been demonstrated [17]. The second EV71 receptor, human P-selectin glycoprotein ligand-1 (PSGL-1/ CD162), is a sialomucin membrane protein expressed mainly in leukocytes, including dendritic cells and macrophages [18]. PSGL-1 was postulated to facilitate the viremic phase of EV71 by enabling replication in circulating leukocytes [19].…”

P-selectin glycoprotein ligand 1 therapy ameliorates established collagen-induced arthritis in DBA/1 mice partly through the suppression of tumour necrosis factor

“…PSGL-1 has binding ability to both L -selectin and E-selectin [21,22], but it is the main highaffinity specific ligand for P-selectin [18]. PSGL-1 is distributed on various cell types such as B cells, T cells ( g / d subset), residential and circulating dendritic cells, CD34 + stem cells and various myeloid cells from the bone marrow show a variable level of expression [23][24][25]. The binding between PSGL-1 and the selectins has been disrupted by the use of antibodies (Ab) raised against the specific selectins or to the ligand [18,21,23,[26][27][28][29].…”