RT Journal Article
SR Electronic
T1 <em>Salmonella</em>-Induced Cell Death Is Not Required  for Enteritis in Calves
JF Infection and Immunity
JO Infect. Immun.
FD American Society for Microbiology
SP 4610
OP 4617
DO 10.1128/IAI.69.7.4610-4617.2001
VO 69
IS 7
A1 Santos, Renato L.
A1 Tsolis, Renée M.
A1 Zhang, Shuping
A1 Ficht, Thomas A.
A1 Bäumler, Andreas J.
A1 Adams, L. Garry
YR 2001
UL http://iai.asm.org/content/69/7/4610.abstract
AB Salmonella enterica serovar Typhimurium causes cell death in bovine monocyte-derived and murine macrophages in vitro by asipB-dependent mechanism. During this process, SipB binds and activates caspase-1, which in turn activates the proinflammatory cytokine interleukin-1β through cleavage. We used bovine ileal ligated loops to address the role of serovar Typhimurium-induced cell death in induction of fluid accumulation and inflammation in this diarrhea model. Twelve perinatal calves had 6- to 9-cm loops prepared in the terminal ileum. They were divided into three groups: one group received an intralumen injection of Luria-Bertani broth as a control in 12 loops. The other two groups (four calves each) were inoculated with 0.75 × 109 CFU of either wild-type serovar Typhimurium (strain IR715) or a sopB mutant per loop in 12 loops. Hematoxylin and eosin-stained sections were scored for inflammation, and terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL)-positive cells were detected in situ. Fluid accumulation began at 3 h postinfection (PI). Inflammation was detected in all infected loops at 1 h PI. The area of TUNEL-labeled cells in the wild-type infected loops was significantly higher than that of the controls at 12 h PI, when a severe inflammatory response and tissue damage had already developed. ThesopB mutant induced the same amount of TUNEL-positive cells as the wild type, but it was attenuated for induction of fluid secretion and inflammation. Our results indicate that serovar Typhimurium-induced cell death is not required to trigger an early inflammatory response and fluid accumulation in the ileum.