title: Interleukin-dependent modulation of HLA-DR expression on CD4and CD8 activated T cells.
abstract: Summary Interleukins (IL) regulate different T-cell surface Ag known as activation markers that have distinct functional roles. In this paper, while studying the influence of some cytokines(IL-12, IL-2 and IL-4) on the expression of several markers [CD69,CD25, CD26, CD3, human leukocyte antigen (HLA-DR), CD45R0] in in vitro activated human T lymphocytes, we observed two groups of donors responding to phytohaemagglutinin (PHA) activation with high or low HLA-DRAg expression. We also found that CD4 and CD8 populations had different HLA-DR densities under PHA activation (particularly the high HLA-DR-expressing group). Interleukins, in a dose-dependent manner (IL-2 partially),upregulated these HLA-DR levels. In 5 day cultures, IL-12 and IL-2 enhanced the CD8/CD4 ratio of activated T cells,which was responsible, in part, for the IL-dependent HLA-DR upregulation.IL-12 and IL-2 also upregulated the HLA-DR expression at the molecular level on CD8, and IL-12 downregulated it on CD4 cells. It seems that IL-4 upregulated HLA-DR by shortening the mitogen-dependent regulation kinetics. We hypothesize that the different effect of each IL on HLA-DR expression might be related to the regulation of the dose of antigenic peptide presentation and, thus, also influence TH1/TH2 dominance.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Santiago de Compostela, Spain.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Salgado
authors.forename: Juan
authors.initials: J
authors.lastname: Lojo
authors.forename: Carmen M
authors.initials: CM
authors.lastname: Fernández-Alonso
authors.forename: JuanE
authors.initials: J
authors.lastname: Viñuela
authors.forename: Oscar J
authors.initials: OJ
authors.lastname: Cordero
authors.forename: Montserrat
authors.initials: M
authors.lastname: Nogueira
mesh_terms: D017252:CD3 Complex / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D005434:Flow Cytometry; D006684:HLA-DR Antigens / Q000096:biosynthesis*; D006801:Humans; D018664:Interleukin-12 / Q000494:pharmacology; D007376:Interleukin-2 / Q000494:pharmacology; D015847:Interleukin-4 / Q000494:pharmacology; D007378:Interleukins / Q000494:pharmacology*; D008213:Lymphocyte Activation
chemical_list: D017252:CD3 Complex; D006684:HLA-DR Antigens; D007376:Interleukin-2; D007378:Interleukins; D018664:Interleukin-12; D015847:Interleukin-4