Recombinant adenovirus expressing ICP47 gene suppresses the ability of dendritic cells by restricting specific T cell responses

• Adenovirus vector which encoded ICP47 gene was constructed.
• Abilities of ICP47 to reduce immunogenicity of gene-modified DCs were evaluated.
• Evidences for long-term persistence of DC-based immunotherapy were proposed.

Adenoviral vectors have been demonstrated to be one of the most effective vehicles to deliver foreign DNA into dendritic cells (DCs). However, the response of host immune systems against foreign gene products is a major obstacle to successful gene therapy. Infected cell protein 47 (ICP47) inhibits MHC Ⅰ antigen presentation pathway by binding to host transporter associated with antigen presentation (TAP), and thereby attenuates of specific cytotoxic T lymphocytes (CTLs) responses and evades the host immune clearance. This subject was designed to construct a recombinant adenovirus expressing His-tag-ICP47 fusion protein to investigate further the role of ICP47 in the elimination of transgene expression. Consequently, a recombinant adenovirus expressing the His-tag-ICP47 fusion protein was successfully constructed and it had the abilities of attenuating the stimulatory capacity of DCs by reducing the proliferation of lymphocytes and cytokine production of perforin compared with those of the r-track group and the control group. Our observations provide the first evidence of the regulation mechanism of ICP47 on DC-based immunotherapy for long-term persistence.