The near epidemic occurrence of fibropapilloma in green sea turtle (Chelonia my das) (Figure 1) significantly threatens the survival of this species which is protected under the U.S. Endangered Species Act. Although collective evidence suggests a viral etiology, the causative virus of green sea turtle fibropapilloma has not been isolated. To facilitate the isolation and characterization of the causative virus(es), we established 13 cell lines from multiple organs/tissues (tumor, kidney, lung, heart, gall bladder, testis, and skin) of green sea turtles with fibropapilloma. Serial subcultivation of cell lines derived from lungs, testis, eye soft tissues and tumors resulted in the formation of tumor-like aggregates, which attained sizes of 1-2 mm in diameter within two weeks (Figure 2). Media from such cultures, when inoculated onto cells derived from healthy turtle embryos, produced similar tumor-like aggregates, suggesting the presence of a transmissible agent.
Isolation and characterization of mutant cell lines defective in transforming growth factor beta signaling.
