Table of Contents Author Guidelines Submit a Manuscript
Clinical and Developmental Immunology
Volume 2012 (2012), Article ID 478052, 6 pages
Research Article

The Average IFN-γ Secreting Capacity of Specific CD8+ T Cells Is Compromised While Increasing Copies of a Single T Cell Epitope Encoded by DNA Vaccine

1Shanghai Public Health Clinical Center, Fudan University, Shanghai 201508, China
2Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
3Key Laboratory of Medical Molecular Virology of Ministry of Education/Health, Fudan University, Shanghai 200032, China
4School of Biology and Basic Medical Sciences, Soochow University, Suzhou 215123, China

Received 20 July 2012; Revised 24 September 2012; Accepted 25 September 2012

Academic Editor: Bapi Pahar

Copyright © 2012 Yanmin Wan et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Previous studies suggested that both the frequency and the mean fluorescence intensity (MFI) of cytokine secreting T cells could be of great value for immunogenicity evaluation of a vaccine. In this study, by constructing epitope-based DNA vaccines encoding a previously identified CD8+ T cell epitope, we investigated the influence of multiplying epitope copies on both the frequency and the MFI of specific IFN-γ secreting CD8+ T cells. We found that frequencies of specific CD8+ T cell could be improved by multiplying epitope copies, while the MFI of IFN-γ secreted by epitope-specific CD8+ T cells decreased synchronously. And further analysis showed that the decrease of MFI was not caused by the functional avidity variation of CD8+ T cell receptor.