[1] Univ Calif Irvine, Sch Med, Dept Ophthalmol, Irvine, CA 92717 USA
[2] Cedars Sinai Med Ctr, Burns & Allen Res Inst, Dept Surg, Los Angeles, CA 90048 USA
[3] Oregon State Univ, Coll Vet Med, Dept Biol Sci, Corvallis, OR 97331 USA
[4] Univ Penn, Dept Microbiol, Philadelphia, PA 19104 USA
[5] Univ Nebraska, Dept Vet & Biomed Sci, Lincoln, NE USA