title: Characterization of rabbit antithymocyte globulins-induced CD25+ regulatory T cells from cells of patients with end-stage renal disease.
abstract: BACKGROUND.: Rabbit antithymocyte globulins (rATGs) are known to convert CD4CD25FoxP3 T cells from healthy individuals to CD4CD25FoxP3 T cells. In this study, we investigated the effect of rATG on the induction of regulatory T cells (Tregs) from blood cells of patients with end-stage renal disease who are candidates for transplantation and rATG-induction therapy. The induced Tregs were analyzed and compared with naturally occurring CD4CD25FoxP3T cells. METHODS.: The CD25 T cells of pretransplant patients (n=7) and healthy controls (n=4) were stimulated with rATG or control rabbit immunoglobulins for 24 hr. The phenotype of induced Tregs was examined by flow cytometry, and their function was studied in the conventional suppression assay. Further characterization was performed by mRNA analyses. RESULTS.: After 24 hr, the percentage of CD4CD25FoxP3CD127 T cells and CD8CD25FoxP3CD127 T cells became higher in the rATG-treated samples compared with the rabbit immunoglobulin-treated samples (P<0.01). The rATG-induced CD25T cells, whether CD4 or CD8 inhibited the allogeneic responses of CD25 effector T cells as vigorously as natural CD25T cells. However, the proportion of FoxP3 within the top 2% rATG-induced CD4CD25T-cells was lower than within the natural CD4CD25T-cells (11%+/-2% vs. 95%+/-5%, P<0.01). The mRNA-expression levels of interleukin-27, interleukin-10, interferon-gamma, perforin, and granzyme B were markedly higher compared with natural CD25T-cells (all P=0.03), whereas CTLA4 (P=0.03), transforming growth factor-beta (P=0.02), and RORgammat (P=0.04) were lower. CONCLUSION.: rATG allows the induction of Tregs from patient peripheral blood mononuclear cell in vitro. In comparison with natural Tregs, the rATG-induced Tregs are phenotypically distinct but have similar regulatory activities. rATG may beneficially contribute to the mechanisms that control alloreactivity.
authors.affiliation: Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands. v.sewgobind@erasmusmc.nl
authors.forename: Varsha D K D
authors.initials: VD
authors.lastname: Sewgobind
authors.forename: Luc J W
authors.initials: LJ
authors.lastname: van der Laan
authors.forename: Marcia M L
authors.initials: MM
authors.lastname: Kho
authors.forename: Rens
authors.initials: R
authors.lastname: Kraaijeveld
authors.forename: Sander S
authors.initials: SS
authors.lastname: Korevaar
authors.forename: Thea
authors.initials: T
authors.lastname: van Dam
authors.forename: Jan N M
authors.initials: JN
authors.lastname: Ijzermans
authors.forename: Willem
authors.initials: W
authors.lastname: Weimar
authors.forename: Carla C
authors.initials: CC
authors.lastname: Baan
mesh_terms: D000818:Animals; D000961:Antilymphocyte Serum / Q000276:immunology*; D016022:Case-Control Studies; D002478:Cells, Cultured; D016207:Cytokines / Q000235:genetics; D003602:Cytotoxicity, Immunologic; D004306:Dose-Response Relationship, Immunologic; D005434:Flow Cytometry; D051858:Forkhead Transcription Factors / Q000378:metabolism*; D053804:Granzymes / Q000235:genetics; D006801:Humans; D016130:Immunophenotyping / Q000379:methods; D053645:Interleukin-2 Receptor alpha Subunit / Q000378:metabolism*; D053699:Interleukin-7 Receptor alpha Subunit / Q000378:metabolism; D007676:Kidney Failure, Chronic / Q000276:immunology* / Q000601:surgery; D016030:Kidney Transplantation; D007963:Leukocytes, Mononuclear / Q000276:immunology*; D054353:Perforin / Q000235:genetics; D010641:Phenotype; D011485:Protein Binding; D012333:RNA, Messenger / Q000378:metabolism; D011817:Rabbits; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D013997:Time Factors
chemical_list: D000961:Antilymphocyte Serum; D016207:Cytokines; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; C508017:IL2RA protein, human; D053645:Interleukin-2 Receptor alpha Subunit; D053699:Interleukin-7 Receptor alpha Subunit; D012333:RNA, Messenger; D054353:Perforin; C509213:GZMB protein, human; D053804:Granzymes