title: Co-inoculation of DNA and protein vaccines induces antigen-specific T cell suppression.
abstract: Immunization can sometimes lead to antigen-specific immune suppression. In this study, we investigated this phenomenon by testing several combinations of DNA and protein vaccines directed against various viruses. We find that co-inoculation of mice with combined DNA and protein vaccines induces immune suppression if the two vaccines are "matched" by targeting the same antigen. Conversely, vaccine combinations never lead to immune suppression if they are derived from different viruses and, thus, mismatched antigenically. We have further identified CD4+CD25- T cells as the type of regulatory T cells induced by and are responsible for suppressing T cell activities in an antigen-specific manner in immunized animals. These regulatory T cells are phenotypically unique in their expression of Foxp3, IL-10, and IFN-gamma. Our study thus shows for the first time that co-administration of antigen-matched DNA and protein vaccines can generate this type of adaptive regulatory T cells.
authors.affiliation: State Key Laboratory for Agro-Biotechnology, Department of Microbiology and Immunology, College of Biological Science, China Agricultural University, Beijing 100094, China.
authors.forename: Youmin
authors.initials: Y
authors.lastname: Kang
authors.forename: Huali
authors.initials: H
authors.lastname: Jin
authors.forename: Guoxing
authors.initials: G
authors.lastname: Zheng
authors.forename: Xiaogang
authors.initials: X
authors.lastname: Du
authors.forename: Chong
authors.initials: C
authors.lastname: Xiao
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Zhang
authors.forename: Shuang
authors.initials: S
authors.lastname: Geng
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Li
authors.forename: Junpeng
authors.initials: J
authors.lastname: Wang
authors.forename: Aoshuang
authors.initials: A
authors.lastname: Chen
authors.forename: Bin
authors.initials: B
authors.lastname: Wang
mesh_terms: D000818:Animals; D000956:Antigens, Viral / Q000276:immunology*; D015704:CD4 Antigens / Q000032:analysis; D016827:CD8 Antigens / Q000032:analysis; D049109:Cell Proliferation; D005260:Female; D005434:Flow Cytometry; D051858:Forkhead Transcription Factors / Q000032:analysis; D007371:Interferon-gamma / Q000032:analysis; D016753:Interleukin-10 / Q000032:analysis; D053645:Interleukin-2 Receptor alpha Subunit / Q000032:analysis; D015847:Interleukin-4 / Q000032:analysis; D007959:Lymphocyte Culture Test, Mixed; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000235:genetics; D014611:Vaccination / Q000379:methods; D019444:Vaccines, DNA / Q000008:administration & dosage / Q000276:immunology*; D014764:Viral Proteins / Q000235:genetics / Q000276:immunology*; D014765:Viral Vaccines / Q000008:administration & dosage / Q000276:immunology*
chemical_list: D000956:Antigens, Viral; D015704:CD4 Antigens; D016827:CD8 Antigens; D051858:Forkhead Transcription Factors; C498833:Foxp3 protein, mouse; D053645:Interleukin-2 Receptor alpha Subunit; D016212:Transforming Growth Factor beta; D019444:Vaccines, DNA; D014764:Viral Proteins; D014765:Viral Vaccines; D016753:Interleukin-10; D015847:Interleukin-4; D007371:Interferon-gamma