title: Phenotypic and functional characterisation of porcine CD4(+)CD25(high) regulatory T cells.
abstract: Over the last years regulatory T cells (Tregs) were defined as CD4(+)CD25(+) T lymphocytes expressing the transcription factor Foxp3 (Forkhead Box P3) with the ability to downregulate various immune responses. In swine the existence of CD4(+)CD25(+) T lymphocytes was described before but nothing is known about the function of this minor cell population to date. Therefore, we studied porcine CD4(+)CD25(+) T cells with regard to major attributes of murine and human Tregs: their phenotype concerning the expression of several T-cell specific antigens, including Foxp3, their IL-10 production and their suppressive capacity. Our results revealed that porcine CD4(+)CD25(+) T cells with high CD25 expression count for about 2-9% of the CD4(+) T-cell subset. They demonstrate a strong Foxp3 expression, a heterogeneous CD45RC-, CD8alpha- and MHC-II-defined phenotype and a moderate IL-10 production. Co-cultivation of increasing numbers of CD4(+)CD25(high) T cells with a constant number of CD4(+)CD25(-) responder-T cells caused a decrease in proliferation of the entire culture. This demonstrates the suppressive capacity of the CD4(+)CD25(high) T-cell subset and - together with their Foxp3 expression - the existence of porcine Tregs.
authors.affiliation: Clinical Immunology, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210 Vienna, Austria.
authors.forename: Tobias
authors.initials: T
authors.lastname: Käser
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Gerner
authors.forename: Sabine E
authors.initials: SE
authors.lastname: Hammer
authors.forename: Martina
authors.initials: M
authors.lastname: Patzl
authors.forename: Armin
authors.initials: A
authors.lastname: Saalmüller
mesh_terms: D000818:Animals; D051858:Forkhead Transcription Factors / Q000032:analysis; D016130:Immunophenotyping; D016753:Interleukin-10 / Q000096:biosynthesis; D013552:Swine / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000502:physiology
chemical_list: D051858:Forkhead Transcription Factors; D016753:Interleukin-10