[1] London Res Inst, S Mimms EN6 3LD, Herts, England
[2] Mem Sloan Kettering Canc Ctr, Program Immunol, New York, NY 10021 USA
[3] Univ Calif San Francisco, Dept Obstet Gynecol & Reprod Sci, San Francisco, CA 94158 USA
[4] Univ Michigan, Sch Med, Dept Human Genet, Howard Hughes Med Inst, Ann Arbor, MI 48109 USA
[5] Univ Michigan, Sch Med, Dept Internal Med, Howard Hughes Med Inst, Ann Arbor, MI 48109 USA