In vivo anti-tumor effect of tumor cell-derived exosomes combined with BCG / 中国肿瘤生物治疗杂志

ABSTRACT

Objective:To study the in vivo anti-tumor effect of exosomes (Exo) combined with bacillus Calmette-Gu?rin vaccine(BCG). Methods:Exo was isolated and purified from culture supernatant of E.G7-OVA tumor cells by density gradient centrifugation. Protein components of Exo were detected by Western blotting. Exo,BCG,Exo combined with BCG (Exo+BCG) or PBS were pre-injected into mice before injection of E.G7-OVA cells,and the anti-tumor effects were observed in each group. Mouse model bearing E.G7-OVA cells was established to examine the immuno-therapy effects of Exo with or without BCG. Cytotoxity of spleen CTL was measured by LDH in different groups. Results:Exo derived from E.G7-OVA cells contained HSP60,OVA,HSC70 and CD63 as detected by Western blotting. Tumor-free rate at 90 d was significantly higher in Exo+BCG vaccinated mice than those in Exo or BCG vaccinated mice as measured by immuno-protective assay (60% vs 20% or 0%,P