1. Departments of Surgical and Radiological Sciences, and
2. Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis;
3. Department of Neurosurgery, Brain Tumor Research Center, University of California, San Francisco;
4. Hermes Biosciences, Inc., San Francisco; and
5. University of California at San Francisco Comprehensive Cancer Center, San Francisco, California