作者单位:Division of Immunology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA[1]Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE 68198-5660, USA[2]Department of Cancer Biology, Dana-Farber Cancer Institute, 44 Binney Street, Boston, MA 02115, USA[3]