Enterobacter cloacae inhibits human norovirus infectivity in gnotobiotic pigs.
Human noroviruses (HuNoVs) are the leading cause of epidemic gastroenteritis worldwide. Study of HuNoV biology has been hampered by the lack of an efficient cell culture system. Recently, enteric commensal bacteria Enterobacter cloacae has been recognized as a helper in HuNoV infection of B cells in vitro. To test the influences of E. cloacae on HuNoV infectivity and to determine whether HuNoV infects B cells in vivo, we colonized gnotobiotic pigs with E. cloacae and inoculated pigs with 2.74 × 10(4) genome copies of HuNoV. Compared to control pigs, reduced HuNoV shedding was observed in E. cloacae colonized pigs, characterized by significantly shorter duration of shedding in post-inoculation day 10 subgroup and lower cumulative shedding and peak shedding in individual pigs. Colonization of E. cloacae also reduced HuNoV titers in intestinal tissues and in blood. In both control and E. cloacae colonized pigs, HuNoV infection of enterocytes was confirmed, however infection of B cells was not observed in ileum, and the entire lamina propria in sections of duodenum, jejunum, and ileum were HuNoV-negative. In summary, E. cloacae inhibited HuNoV infectivity, and B cells were not a target cell type for HuNoV in gnotobiotic pigs, with or without E. cloacae colonization.
Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA.
Shaohua
S
Lei
Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA.
Helen
H
Samuel
Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA.
Erica
E
Twitchell
Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA.
Tammy
T
Bui
Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA.
Ashwin
A
Ramesh
Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA.
Ke
K
Wen
Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA.
Mariah
M
Weiss
Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA.
Guohua
G
Li
Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA.
Xingdong
X
Yang
Division of Infectious Diseases, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.
Xi
X
Jiang
Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA.
Lijuan
L
Yuan
D000818:Animals; D001402:B-Lymphocytes / Q000382:microbiology / Q000821:virology; D001769:Blood / Q000382:microbiology / Q000821:virology; D017250:Caliciviridae Infections / Q000097:blood* / Q000382:microbiology; D016972:Enterobacter cloacae / Q000502:physiology*; D005759:Gastroenteritis / Q000097:blood / Q000382:microbiology / Q000821:virology*; D016679:Genome, Viral; D005856:Germ-Free Life; D006801:Humans; D007422:Intestines / Q000382:microbiology / Q000821:virology; D029322:Norovirus / Q000235:genetics / Q000472:pathogenicity*; D034421:Sus scrofa; D013552:Swine; D019562:Viral Load; D017201:Virus Shedding