Enhanced immune responses to an adenovirus CEA vaccine in CD4⁺CD25⁺ regulatory T-cell inactivated mice

Abstract

Evaluation of: Elia L, Aurisicchio L, Facciabene A et al. CD4⁺CD25⁺ regulatory T-cell inactivation in combination with adenovirus vaccines enhances T-cell responses and protects mice from tumor challenge. Cancer Gene Ther. DOI: 10.1038/sj.cgt.7701004 (2006) (Epub ahead of print).

Numerous cancer vaccine clinical trials have been carried out using various antigen-delivery systems and adjuvants. However, the therapeutic outcomes in patients have been minimal. There are numerous reasons for this and one of the current hypotheses is the inhibitory effects of regulatory T cells (T_reg) on T-cell effectors. Since most tumor antigens are self antigens, antitumor responses to these antigens are dampened by T_reg that are present to prevent autoreactive T cells from damaging healthy tissue. The paper by Elia and colleagues describes an alternative strategy to overcome the suppressive effects of T_reg cells and generate enhanced cellular responses.

Keywords::

• adenovirus
• anti-CD25
• carcinoembryonic antigen
• gene therapy
• regulatory T cell
• vaccine

Acknowledgements

I would like to thank the Susan Komen Breast Cancer Foundation for providing funding for development of breast cancer vaccines.