Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, CA, USA.|Department of Biostatistics and Computational Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.|Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, CA, USA.|Department of Molecular Microbiology and Immunology, Keck School of Medicine, University of Southern California, CA, USA.