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古市 好宏
Department School of Medicine(Tokyo Women's Medical University Adachi Medical Center), School of Medicine Position Associate Professor |
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| Article types | Original article |
| Language | English |
| Peer review | Peer reviewed |
| Title | Depletion of CD25+CD4+T cells (Tregs) enhances the HBV-specific CD8+ T cell response primed by DNA immunization. |
| Journal | Formal name：World journal of gastroenterology Abbreviation：World J Gastroenterol ISSN code：10079327/10079327 |
| Domestic / Foregin | Foregin |
| Volume, Issue, Page | 11(24),pp.3772-7 |
| Author and coauthor | Furuichi Yoshihiro, Tokuyama Hirotake, Ueha Satoshi, Kurachi Makoto, Moriyasu Fuminori, Kakimi Kazuhiro |
| Publication date | 2005/06 |
| Summary | AIM:Persistent hepatitis B virus (HBV) infection is characterized by a weak CD8(+) T cell response to HBV. Immunotherapeutic strategies that overcome tolerance and boost these suboptimal responses may facilitate viral clearance in chronically infected individuals. Therefore, we examined whether CD25(+)CD4(+) regulatory T (Treg) cells might be involved in a inhibition of CD8(+) T cell priming or in the modulation of the magnitude of the 'peak' antiviral CD8(+) T cell response primed by DNA immunization.METHODS:B10.D2 mice were immunized once with plasmid pCMV-S. Mice received 500 microg of anti-CD25 mAb injected intraperitoneally 3 d before DNA immunization to deplete CD25(+) cells. Induction of HBV-specific CD8(+) T cells in peripheral blood mononuclear cells (PBMCs) was measured by S28-39 peptide loaded DimerX staining and their function was analyzed by intracellular IFN-gamma staining.RESULTS:DNA immunization induced HBV-specific CD8(+) T cells. At the peak T cell response (d 10), 7.1+/-2.0% of CD8(+) T cells were HBV-specific after DNA immunization, whereas 12.7+/-3.2% of CD8(+) T cells were HBV-specific in Treg-depleted mice, suggesting that DNA immunization induced more antigen-specific CD8(+) T cells in the absence of CD25(+) Treg cells (n = 6, P<0.05). Similarly, fewer HBV-specific memory T cells were detected in the presence of these cells (1.3+/-0.4%) in comparison to Treg-depleted mice (2.6+/-0.9%) on d 30 after DNA immunization (n = 6, P<0.01). Both IFN-gamma production and the avidity of the HBV-specific CD8(+) T cell response to antigen were higher in HBV-specific CD8(+) T cells induced in the absence of Treg cells.CONCLUSION:CD25(+) Treg cells suppress priming and/or expansion of antigen-specific CD8(+) T cells during DNA immunization and the peak CD8(+) T cell response is enhanced by depleting this cell population. Furthermore, Treg cells appear to be involved in the contraction phase of the CD8(+) T cell response and may affect the quality of memory |
| DOI | 10.3748/wjg.v11.i24.3772 |
| PMID | 15968737 |