Dendritic cells fused with mastocytoma cells elicit therapeutic antitumor immunity

Abstract

Characterization of the spontaneous immune response that frequently occurs in tumor‐bearing animals, as well as immunization using dendritic cells pulsed with tumor antigens, suggests that a limiting factor of the tumor‐specific immune response may be a defect in the co‐stimulatory signal that is required for optimal activation of T cells. In this work, we describe a new approach to improve the antigen‐presenting capacity of tumor cells, which does not require a source of purified tumor‐associated antigen. We fused P815 mastocytoma cells with bone marrow‐derived dendritic cells. We obtained one hybrid that displayed the phenotypic and functional properties of dendritic cells and expressed mRNA coding for the tumor‐associated antigen P815 A/B. Injections of irradiated hybrid cells prevented the growth of pre‐implanted mastocytoma and induced long‐lasting tumor resistance. Int. J. Cancer76:250–258, 1998.