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Nunes, J.S. et al. Morphologic and cytokine profile characterization of Salmonella enterica serovar typhimurium infection in calves with bovine leukocyte adhesion deficiency. Vet. Pathol. 47, 322-333

Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, Texas, USA.
Veterinary Pathology (Impact Factor: 2.04). 03/2010; 47(2):322-33. DOI: 10.1177/0300985809358037
Source: PubMed

ABSTRACT The role of neutrophils in the pathogenesis of Salmonella enterica Typhimurium-induced ruminant and human enteritis and diarrhea has yet to be characterized with in vivo models. To address this question, the in vivo bovine ligated ileal loop model of nontyphoidal salmonellosis was used in calves with the naturally occurring bovine leukocyte adhesion deficiency (BLAD) mutation whose neutrophils are unable to extravasate and infiltrate the extravascular matrix. Data obtained from 4 BLAD Holstein calves homozygous for BLAD (CD18-), 1 to 5 weeks of age, were compared with 4 controls, age-matched Holstein calves negative for BLAD (CD18+). Morphologic studies revealed that infection of CD18- calves with S Typhimurium resulted in no significant tissue infiltration by neutrophils, less tissue damage, reduced luminal fluid accumulation, and increased bacterial invasion, when compared with CD18+ calves. Ultrastructurally, lesions in enterocytes induced by S Typhimurium infection in CD18- calves--including attachment and disruption of the brush border, apical membrane ruffling formation, and cellular degeneration--were similar to the ones reported in the literature for CD18- calves. Study of cytokine gene expression by quantitative real-time polymerase chain reaction revealed that early stages of acute infection (4-8 hours postinfection) were associated with increased interleukin 8 gene expression in the absence of tissue influx of neutrophils in CD18- calves, whereas later stages of infection (12 hours postinfection) were associated with increased expression of growth-related oncogene alpha in the presence of neutrophil influx in CD18+ calves. In contrast, the proinflammatory cytokines interleukin 1beta and tumor necrosis factor alpha were poorly correlated with the presence or absence of tissue neutrophils.

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    • "As a component of the innate host immune response, the inflammatory process should be seen as a host mechanism for preventing the spread of infection, which to some extent is completely correct, since in the absence of a neutrophilic response, Salmonella tends to spread more efficiently to systemic sites of infection, both in the mouse (53) as well as in cattle (54). These experimental observations parallel clinical disease since serotype Typhi that causes systemic infections does not elicit a significant intestinal neutrophilic response (10). "
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    • "). S. Typhimurium infection of CD18- deficient calves, whose neutrophils are unable to extravasate, does not result in this severe epithelial damage (Nunes et al., 2010). This finding suggests that neutrophils are largely responsible for the collateral tissue damage accompanying exudative inflammation, thereby contributing to intestinal fluid accumulation and diarrhea. "
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    • "Similar results have been reported in Egypt (Moussa et al., 2010) and other countries of the world (Davies et al., 2004; Threlfal et al., 2006; Nunes et al., 2010). "
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