[1] Howard Hughes Medical Institute,Department of Comparative Medicine
[2] ,Immunology Division
[3] Department of Immunology,undefined
[4] ,undefined
[5] University of Washington,undefined
[6] Seattle,undefined
[7] Washington 98195,undefined
[8] USA,undefined
[9] The Walter and Eliza Hall Institute,undefined
[10] Institute for Cancer Genetics and Herbert Irving Comprehensive Cancer Center,undefined
[11] Columbia University,undefined
[12] New York,undefined
[13] New York 10032,undefined
[14] USA,undefined
[15] Present address: Department of Immunology,undefined
[16] Memorial Sloan-Kettering Cancer Center,undefined
[17] New York,undefined
[18] New York 10021,undefined
[19] USA.,undefined