Strengthened tumor antigen immune recognition by inclusion of a recombinant Eimeria antigen in therapeutic cancer vaccination

In this report, we investigated whether rAd5-rEA could promote and/or alter cytotoxic memory responses toward carcinoembryonic antigen (CEA), a colorectal cancer-related TAA. We found that the addition of rAd5-rEA to an Ad-based CEA vaccine induced a dose-dependent increase in several anti-CEA T and B cell responses. Moreover, inclusion of rAd5-rEA increased the number of CEA-derived antigenic epitopes that elicited significant cell-mediated and IgG-mediated recognition. These enhanced anti-CEA immune responses also translated into superior CEA-targeted cell killing, as evaluated by an in vivo cytotoxic T lymphocyte assay. Overall, these results suggest that co-administration of rAd5-rEA with a tumor antigen vaccine can substantially boost and broaden the TAA-specific adaptive memory response, thereby validating the potential of rAd5-rEA to be a beneficial adjuvant during therapeutic cancer vaccination.
Source: Cancer Immunology, Immunotherapy - Category: Cancer & Oncology Source Type: research