title: Immunomodulation of human CD8⁺ T cells by thymoglobulin in vitro.
abstract: The major mechanism of thymoglobulin in inhibiting allograft rejection involves lymphocyte depletion. However, its role in modulating CD8(+) cells has remained unclear. This study evaluated the immunologic effects of thymoglobulin on human CD8(+) cells. Purified CD8(+) cells were pretreated with thymoglobulin followed by incubation for 72 hours. The culture supernates and cells were analyzed using real-time quantitative polymerase chain reaction (RT-PCR), multiplex cytokine detection assay, and flow cytometry. RT-PCR showed that thymoglobulin-treated CD8(+) cells up-regulated transcripts for CD25, CTLA-4, OX40, GITR, Foxp3, IFN-γ, interleukin (IL)-10, and IL-2 when compared with isotype control immunoglobulin (Ig). The expression for GITR and IL-2 transcripts was down-regulated at 72 hours after incubation. The release of IFN-γ, IL-10, and IL-2 from thymoglobulin-pretreated CD8(+) cells was detected using multiplex assay after 24-hour incubation, and these cytokine levels were decreased after incubation for 48 and 72 hours. Flow cytometry demonstrated up-regulation of CD69 and CD25 expression after treatment. The surface CTLA-4 and intracellular Foxp3 expression was not increased in thymoglobulin-treated cells. Our results demonstrated that thymoglobulin-treated CD8(+) cells up-regulate CD25, and multiple costimulatory molecules at the transcriptional level. The up-regulation of transcripts of immune regulatory cytokines accompanies the release of these cytokines. The unique effects of thymoglobulin on CD8(+) cells may be an important mechanism for its action in inducing immunosuppression and immunomodulation.
authors.affiliation: Department of Anesthesiology, Jinan Central Hospital affiliated with Shandong University, Jinan, People's Republic of China.
authors.forename: L-Z
authors.initials: LZ
authors.lastname: Yu
authors.forename: Y
authors.initials: Y
authors.lastname: Fang
authors.forename: L
authors.initials: L
authors.lastname: Zhu
authors.forename: Z-G
authors.initials: ZG
authors.lastname: Sun
authors.forename: H
authors.initials: H
authors.lastname: Xu
mesh_terms: D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism; D000945:Antigens, Differentiation, T-Lymphocyte / Q000235:genetics / Q000378:metabolism; D000961:Antilymphocyte Serum / Q000494:pharmacology*; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D060908:CTLA-4 Antigen / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D005434:Flow Cytometry; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D053450:Glucocorticoid-Induced TNFR-Related Protein / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D053645:Interleukin-2 Receptor alpha Subunit / Q000235:genetics / Q000378:metabolism; D037181:Lectins, C-Type / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D053262:Receptors, OX40 / Q000235:genetics / Q000378:metabolism; D013997:Time Factors; D014158:Transcription, Genetic / Q000187:drug effects; D015854:Up-Regulation; D000099192:CD69 Antigens
chemical_list: D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D000961:Antilymphocyte Serum; D060908:CTLA-4 Antigen; D016207:Cytokines; D051858:Forkhead Transcription Factors; D053450:Glucocorticoid-Induced TNFR-Related Protein; D007166:Immunosuppressive Agents; D053645:Interleukin-2 Receptor alpha Subunit; D037181:Lectins, C-Type; D012333:RNA, Messenger; D053262:Receptors, OX40; D000099192:CD69 Antigens; C556706:CTLA4 protein, human; C418974:FOXP3 protein, human; C508017:IL2RA protein, human; C491405:TNFRSF18 protein, human; C505716:TNFRSF4 protein, human; C512542:thymoglobulin