title: Differential expression of the cytokine receptors for human interleukin (IL)-12 and IL-18 on lymphocytes of both CD45RA and CD45RO phenotype from tonsils, cord and adult peripheral blood.
abstract: The objective of this study was to demonstrate the variable expression of cytokine receptors on naive versus memory human CD4+ T cell subpopulations in tonsillar tissue, cord blood and adult blood. We prove that the receptors for both interleukin (IL)-12 and IL-18 are expressed exclusively on memory T cells. This observation was seen not only on the CD45RO+ memory T cells but also on a significant percentage of the CD45RA+, CD62L-, CD27- and CCR7- populations. Furthermore, CD45RA+ CD62L+, CD27+ or CCR7+ CD4+ T cells that expressed IL-12Rbeta1 and IL-18Ralpha did not express CD31, a marker for recent thymic emigrants. We reveal that cord blood lymphocytes do not express IL-12Rbeta1 whereas IL-18Ralpha expression was detected at low levels. Importantly, the IL-12Rbeta2 signalling chain, which is absent in all resting T cells, was up-regulated in both CD45RA+ and CD45RO+ T cells as a result of stimulation with anti-CD3 and anti-CD28 in vitro. This observed up-regulation was, however, restricted to 80% of the total CD4+ population. Finally, a very small proportion of the CD4+ CD45RO+ tonsillar T cells expressed the IL-12 and IL-18 receptors, thereby establishing the differential expression of these receptors between peripheral and tonsillar memory T cell subpopulations.
authors.affiliation: Institució Catalana de Recerca i Estudis Avançats, Badalona, Spain. mbofill@ns.hugtip.scs.es
authors.forename: M
authors.initials: M
authors.lastname: Bofill
authors.forename: E
authors.initials: E
authors.lastname: Almirall
authors.forename: A
authors.initials: A
authors.lastname: McQuaid
authors.forename: R
authors.initials: R
authors.lastname: Peña
authors.forename: R
authors.initials: R
authors.lastname: Ruiz-Hernandez
authors.forename: M
authors.initials: M
authors.lastname: Naranjo
authors.forename: L
authors.initials: L
authors.lastname: Ruiz
authors.forename: B
authors.initials: B
authors.lastname: Clotet
authors.forename: F E
authors.initials: FE
authors.lastname: Borràs
mesh_terms: D000293:Adolescent; D000328:Adult; D018106:CD28 Antigens / Q000276:immunology; D017252:CD3 Complex / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D005312:Fetal Blood / Q000276:immunology; D006801:Humans; D007156:Immunologic Memory / Q000276:immunology; D016130:Immunophenotyping / Q000379:methods; D018664:Interleukin-12 / Q000276:immunology; D020382:Interleukin-18 / Q000276:immunology; D053727:Interleukin-18 Receptor alpha Subunit; D017493:Leukocyte Common Antigens / Q000276:immunology*; D008213:Lymphocyte Activation / Q000276:immunology; D008264:Macrophages / Q000276:immunology; D014066:Palatine Tonsil / Q000276:immunology*; D018123:Receptors, Interleukin / Q000032:analysis* / Q000276:immunology*; D053707:Receptors, Interleukin-12; D053724:Receptors, Interleukin-18; D015854:Up-Regulation / Q000276:immunology
chemical_list: D018106:CD28 Antigens; D017252:CD3 Complex; C508572:IL18R1 protein, human; D020382:Interleukin-18; D053727:Interleukin-18 Receptor alpha Subunit; D018123:Receptors, Interleukin; D053707:Receptors, Interleukin-12; D053724:Receptors, Interleukin-18; D018664:Interleukin-12; D017493:Leukocyte Common Antigens