[1] Univ Chicago, Dept Med, Rheumatol Sect, Chicago, IL 60637 USA
[2] Univ Chicago, Comm Immunol, Chicago, IL 60637 USA
[3] Oklahoma Med Res Fdn, Dept Clin Immunol, Oklahoma City, OK 73104 USA
[4] Emory Univ, Sch Med, Emory Vaccine Ctr, Dept Microbiol & Immunol, Atlanta, GA 30322 USA