Figure 3.

Maraba mutants retain their killing potency in cancer cells yet are attenuated on normal cells. (a) Mutations in the M and G protein attenuate the ability of Maraba to kill GM38 cells. Viability assays were performed in GM38 cells at 72 hours postinfection with Maraba, and the indicated Maraba mutants. (b) Maraba and Maraba variants are highly lytic in a variety of tumor cell lines. Cells infected with rMaraba WT and the Maraba variants were assayed for viability using resazurin. (c) Engineering L123W mutation into Q242R Maraba mutant reverts plaque sizes to a wild-type phenotype on tumor cells. (d) Time course of viral protein induction. Immunoblots of OVCAR4 mock-infected and MR, rMaraba wild type, Q242R-, L123W-, and MG1-infected cells. WT, wild type.