title: Differential expressions of heme oxygenase-1 gene in CD25- and CD25+ subsets of human CD4+ T cells.
abstract: Growing evidence suggests that the immunomodulatory heme oxygenase-1 (HO-1) may have an important role in regulating T-cell responses. In this study, we investigated whether CD4(+)CD25(-) and CD4(+)CD25(+) T cells of human CD4(+) subpopulation could differentially express HO-1. Our results obtained from qualitative reverse transcriptase-polymerase chain reaction and quantitative flow cytometry analyses revealed that the CD4(+)CD25(+) T cells constitutively express HO-1 and that T cell stimulation with plate-bound anti-CD3 in combination with soluble anti-CD28 not only induced HO-1 gene expression in the CD4(+)CD25(-) T cells but also up-regulated HO-1 gene expression in the CD4(+)CD25(+) T cells. Our further studies showed that CD28 signal alone was enough to induce HO-1 expression and CD3 signal, of which signal alone did not induce HO-1 expression, was required at least for full HO-1 expression in both CD25(-) and CD25(+) subsets of human CD4(+) T cells. In addition, transfection of human Jurkat T cells with HO-1 suppressed the cellular proliferation, and this effect was reversed by zinc protoporphyrin, a specific HO competitive inhibitor. Taken together, we have first reported that human CD4(+)CD25(+) regulatory T cells constitutively express HO-1 and that HO-1 inhibits Jurkat T cell proliferation.
authors.affiliation: Medicinal Resources Research Center (MRRC), Wonkwang University, Iksan, 570-749, Chonbuk, Republic of Korea.
authors.forename: Hyun-Ock
authors.initials: HO
authors.lastname: Pae
authors.forename: Gi-Su
authors.initials: GS
authors.lastname: Oh
authors.forename: Byung-Min
authors.initials: BM
authors.lastname: Choi
authors.forename: Soo-Cheon
authors.initials: SC
authors.lastname: Chae
authors.forename: Hun-Taeg
authors.initials: HT
authors.lastname: Chung
mesh_terms: D018106:CD28 Antigens / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000201:enzymology* / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D015971:Gene Expression Regulation, Enzymologic; D006419:Heme Oxygenase (Decyclizing) / Q000235:genetics* / Q000378:metabolism*; D051547:Heme Oxygenase-1; D006801:Humans; D018189:Immunomagnetic Separation; D019169:Jurkat Cells; D008565:Membrane Proteins; D015375:Receptors, Interleukin-2 / Q000378:metabolism*; D016176:T-Lymphocyte Subsets / Q000201:enzymology*
chemical_list: D018106:CD28 Antigens; D008565:Membrane Proteins; D015375:Receptors, Interleukin-2; C496541:HMOX1 protein, human; D006419:Heme Oxygenase (Decyclizing); D051547:Heme Oxygenase-1