Oral administration of poly-gamma-glutamic acid significantly enhances the antitumor effect of HPV16 E7-expressing Lactobacillus casei in a TC-1 mouse model.

Oral administration of poly-gamma-glutamic acid significantly enhances the antitumor effect of HPV16 E7-expressing Lactobacillus casei in a TC-1 mouse model. J Microbiol Biotechnol. 2019 Aug 07;: Authors: Kim E, Yang J, Sung MH, Poo H Abstract The conventional prophylactic vaccines for human papillomavirus (HPV) efficiently prevent infection with high-risk HPV types, but they do not promote therapeutic effects against cervical cancer. Previously, we developed HPV16 E7-expressing Lactobacillus casei (L. casei-E7) as a therapeutic vaccine candidate for cervical cancer, which induces antitumor therapeutic effects in a TC-1 murine cancer model. To improve the therapeutic effect of L. casei-E7, we performed co-treatment with poly-gamma-glutamic acid (γ-PGA), a safe and edible biomaterial naturally secreted by Bacillus subtilis. We investigated their synergistic effect to improve antitumor efficacy in a murine cancer model. The treatment with γ-PGA did not show in vitro cytotoxicity against TC-1 tumor cells; however, an enhanced innate immune response including activation of dendritic cells was observed. Mice co-administered with γ-PGA and L. casei-E7 showed significantly suppressed growth of TC-1 tumor cells and an increased survival rate in TC-1 mouse models compared to those of mice vaccinated with L. casei-E7 alone. The administration of γ-PGA markedly enhanced the activation of natural killer (NK) cells but did not increase the E7...
Source: Journal of Microbiology and Biotechnology - Category: Biotechnology Authors: Tags: J Microbiol Biotechnol Source Type: research