The utility of cells as vehicles for oncolytic virus therapies.

Oncolytic viruses are emerging as promising anticancer agents, but efficient delivery and dispersal at sites of tumor growth remain a significant challenge. Viruses can be efficiently neutralized by antiviral antibodies in the blood stream or sequestered by phagocytic cells in the liver and spleen, and they often fail to extravasate and migrate in tumor deposits or in the tissues to which tumors metastasize. As an alternative to the administration of naked viruses, virus-infected carrier cells are currently under investigation as vehicles to deliver oncolytic viruses more reliably, uniformly and efficiently to sites of tumor growth in the body, even in virus-immune individuals. Aside from their virus chaperoning capabilities, certain carrier cell types may exert additional antitumor activities that operate in synergy with the oncolytic virus infection to mediate tumor regression.