title: Coexpression of GD3 ganglioside with CD45RO in resting and activated human T lymphocytes.
abstract: The ganglioside GD3 is preferentially expressed on the surface of malignant T cell lymphoblasts and on resting T cells which express the memory cell phenotype, CD45RA-CD29+. However, GD3 expression in activated T cells and its potential function in proliferating normal and malignant T cells are unclear. Utilizing three-color immunostaining and flow cytometry, we examined changes in the expression of GD3 in conjunction with the RA and RO isoforms of CD45 during in vitro T cell activation. GD3 was equally expressed in resting CD4 and CD8 cells and was specifically found in the CD45RO+RA population. Activation of T cells with PHA resulted in an increased percentage of GD3+ cells. This increase was evident by the first day and was observed in the CD45RO (naive cell) population; by 2 days, GD3 was expressed heterogeneously in a large population of CD45RO+RA+ cells. Further activation of T cells with PHA or anti-CD3 monoclonal antibody (OKT3) resulted in a further increase in GD3-expressing cells, and the increase in GD3 density correlated with increased CD45RO and loss of CD45RA. In contrast, increases in GD3 and interleukin-2 receptor (CD25) expression in response to PHA or OKT3 occurred independently, indicating that the GD3/ CD45RO coexpression observed was not a general consequence of cell activation. The results provide evidence for specific comodulation of GD3 and CD45RO during T cell mitogenesis, and thus suggest that these molecules may colocalize on the T cell surface.
authors.affiliation: Center for Cancer and Transplantation Biology, Children's Research Institute, Washington, DC 20010, USA.
authors.forename: W D
authors.initials: WD
authors.lastname: Merritt
authors.forename: B J
authors.initials: BJ
authors.lastname: Taylor
authors.forename: V
authors.initials: V
authors.lastname: Der-Minassian
authors.forename: G H
authors.initials: GH
authors.lastname: Reaman
mesh_terms: D000328:Adult; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D005732:Gangliosides / Q000276:immunology*; D018740:Genetic Heterogeneity; D006801:Humans; D017493:Leukocyte Common Antigens / Q000276:immunology*; D008213:Lymphocyte Activation; D016853:Muromonab-CD3 / Q000276:immunology; D010835:Phytohemagglutinins / Q000494:pharmacology; D015375:Receptors, Interleukin-2 / Q000276:immunology
chemical_list: D005732:Gangliosides; D016853:Muromonab-CD3; D010835:Phytohemagglutinins; D015375:Receptors, Interleukin-2; C026226:ganglioside, GD3; D017493:Leukocyte Common Antigens