Bacteria Biohybrid Oral Vaccines For Colorectal Cancer Treatment Reduce Tumor Growth And Increase Immune Infiltration

Bacteria biohybrid-based vaccine delivery systems, which integrate a vaccine carrier with live non-pathogenic bacteria, are hypothesized to have improved immunostimulating potential. The aim of this study was to develop oral bacteria biohybrid-based vaccines to treat a mouse model of colorectal cancer. E. coli were combined with tumor antigen-and adjuvant-containing emulsions or liposomes. Emulsion and liposome biohybrid vaccines demonstrated in vitro and in vivo therapeutic potential. Bacteria biohy-brid vaccines significantly increased the expression of CD40(+), CD80(+) and CD86(+) on murine bone marrow-derived dendritic cells. Mice vaccinated with emulsion biohybrid vaccines had an increased CD8(+) T cell infiltration into tumors and developed three-fold smaller tumors compared to the mice that received emulsion vaccine without E. coli. (C) 2021 Elsevier Ltd. All rights reserved.