Limits...
Back to the future: studying cholera pathogenesis using infant rabbits.

Ritchie JM, Rui H, Bronson RT, Waldor MK - MBio (2010)

Bottom Line: CT induced extensive exocytosis of mucin from intestinal goblet cells, and wild-type V. cholerae was predominantly found in close association with mucin.These findings suggest that CT-dependent mucin secretion significantly influences V. cholerae's association with the host intestine and its exit from the intestinal tract.Our model should facilitate identification and analyses of factors that may govern V. cholerae infection, survival, and transmission, such as mucin.

View Article: PubMed Central - PubMed

Affiliation: Channing Laboratory, Brigham and Women’s Hospital, Boston, Massachusetts, USA.

ABSTRACT
Cholera is a severe diarrheal disease, caused by Vibrio cholerae, for which there has been no reproducible, nonsurgical animal model. Here, we report that orogastric inoculation of V. cholerae into 3-day-old rabbits pretreated with cimetidine led to lethal, watery diarrhea in virtually all rabbits. The appearance and chemical composition of the rabbit diarrheal fluid were comparable to those of the "rice-water stool" produced by cholera patients. As in humans, V. cholerae mutants that do not produce cholera toxin (CT) and toxin-coregulated pilus (TCP) did not induce cholera-like disease in rabbits. CT induced extensive exocytosis of mucin from intestinal goblet cells, and wild-type V. cholerae was predominantly found in close association with mucin. Large aggregates of mucin-embedded V. cholerae were observed, both attached to the epithelium and floating within the diarrheal fluid. These findings suggest that CT-dependent mucin secretion significantly influences V. cholerae's association with the host intestine and its exit from the intestinal tract. Our model should facilitate identification and analyses of factors that may govern V. cholerae infection, survival, and transmission, such as mucin. In addition, our results using nontoxigenic V. cholerae suggest that infant rabbits will be useful for study of the reactogenicity of live attenuated-V. cholerae vaccines.

No MeSH data available.


Related in: MedlinePlus

Scanning electron micrographs of the distal small intestines of rabbits inoculated with wild-type V. cholerae (A, C, and E) or the ctxAB mutant (B, D, and F). (A and B) Low-magnification images showing macroscopic material (arrow) on the villi in rabbits inoculated with the wild type (A) but not the ctxAB mutant (B). (C to F) Higher magnification reveals that this material contains numerous V. cholerae organisms (C and E), whereas the ctxAB mutant has a patchy distribution and is in direct apposition to the brush border microvilli (D [arrows] and F). Goblet cells, identified by their shorter, darker microvilli, are seen in panel F. Tissue samples from at least five rabbits were examined.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC2912669&req=5

f7: Scanning electron micrographs of the distal small intestines of rabbits inoculated with wild-type V. cholerae (A, C, and E) or the ctxAB mutant (B, D, and F). (A and B) Low-magnification images showing macroscopic material (arrow) on the villi in rabbits inoculated with the wild type (A) but not the ctxAB mutant (B). (C to F) Higher magnification reveals that this material contains numerous V. cholerae organisms (C and E), whereas the ctxAB mutant has a patchy distribution and is in direct apposition to the brush border microvilli (D [arrows] and F). Goblet cells, identified by their shorter, darker microvilli, are seen in panel F. Tissue samples from at least five rabbits were examined.

Mentions: Scanning electron microscopy (SEM) images of tissue from rabbits infected with wild-type V. cholerae or the ctxAB mutant support this model. Low-magnification SEM images revealed striking differences between rabbits infected with wild-type V. cholerae and those infected with the ctxAB mutant. In samples from rabbits inoculated with wild-type V. cholerae, significant quantities of macroscopic material partially covered the villi (Fig. 7A and C, arrows). This material was not observed in samples from rabbits infected with the ctxAB mutant (compare Fig. 7A and B). Higher-magnification analyses revealed that this material corresponds to a dense matrix, presumably containing mucin as well as bacteria (Fig. 7E). These images also suggest that this matrix is only loosely adherent to the underlying tissue; numerous sites where it appeared to be detaching from the epithelium were detected. In contrast, high-magnification SEM images of intestines containing the V. cholerae ctxAB mutant reveal that these bacteria were not surrounded by an adherent matrix but instead are in direct contact with the brush border microvilli (Fig. 7D and F). Thus, these studies reveal a profound difference between the means by which wild-type V. cholerae and the ctxAB mutant adhere to epithelial tissue, which presumably reflects their differential effects on the exocytosis of mucin from goblet cells.


Back to the future: studying cholera pathogenesis using infant rabbits.

Ritchie JM, Rui H, Bronson RT, Waldor MK - MBio (2010)

Scanning electron micrographs of the distal small intestines of rabbits inoculated with wild-type V. cholerae (A, C, and E) or the ctxAB mutant (B, D, and F). (A and B) Low-magnification images showing macroscopic material (arrow) on the villi in rabbits inoculated with the wild type (A) but not the ctxAB mutant (B). (C to F) Higher magnification reveals that this material contains numerous V. cholerae organisms (C and E), whereas the ctxAB mutant has a patchy distribution and is in direct apposition to the brush border microvilli (D [arrows] and F). Goblet cells, identified by their shorter, darker microvilli, are seen in panel F. Tissue samples from at least five rabbits were examined.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2912669&req=5

f7: Scanning electron micrographs of the distal small intestines of rabbits inoculated with wild-type V. cholerae (A, C, and E) or the ctxAB mutant (B, D, and F). (A and B) Low-magnification images showing macroscopic material (arrow) on the villi in rabbits inoculated with the wild type (A) but not the ctxAB mutant (B). (C to F) Higher magnification reveals that this material contains numerous V. cholerae organisms (C and E), whereas the ctxAB mutant has a patchy distribution and is in direct apposition to the brush border microvilli (D [arrows] and F). Goblet cells, identified by their shorter, darker microvilli, are seen in panel F. Tissue samples from at least five rabbits were examined.
Mentions: Scanning electron microscopy (SEM) images of tissue from rabbits infected with wild-type V. cholerae or the ctxAB mutant support this model. Low-magnification SEM images revealed striking differences between rabbits infected with wild-type V. cholerae and those infected with the ctxAB mutant. In samples from rabbits inoculated with wild-type V. cholerae, significant quantities of macroscopic material partially covered the villi (Fig. 7A and C, arrows). This material was not observed in samples from rabbits infected with the ctxAB mutant (compare Fig. 7A and B). Higher-magnification analyses revealed that this material corresponds to a dense matrix, presumably containing mucin as well as bacteria (Fig. 7E). These images also suggest that this matrix is only loosely adherent to the underlying tissue; numerous sites where it appeared to be detaching from the epithelium were detected. In contrast, high-magnification SEM images of intestines containing the V. cholerae ctxAB mutant reveal that these bacteria were not surrounded by an adherent matrix but instead are in direct contact with the brush border microvilli (Fig. 7D and F). Thus, these studies reveal a profound difference between the means by which wild-type V. cholerae and the ctxAB mutant adhere to epithelial tissue, which presumably reflects their differential effects on the exocytosis of mucin from goblet cells.

Bottom Line: CT induced extensive exocytosis of mucin from intestinal goblet cells, and wild-type V. cholerae was predominantly found in close association with mucin.These findings suggest that CT-dependent mucin secretion significantly influences V. cholerae's association with the host intestine and its exit from the intestinal tract.Our model should facilitate identification and analyses of factors that may govern V. cholerae infection, survival, and transmission, such as mucin.

View Article: PubMed Central - PubMed

Affiliation: Channing Laboratory, Brigham and Women’s Hospital, Boston, Massachusetts, USA.

ABSTRACT
Cholera is a severe diarrheal disease, caused by Vibrio cholerae, for which there has been no reproducible, nonsurgical animal model. Here, we report that orogastric inoculation of V. cholerae into 3-day-old rabbits pretreated with cimetidine led to lethal, watery diarrhea in virtually all rabbits. The appearance and chemical composition of the rabbit diarrheal fluid were comparable to those of the "rice-water stool" produced by cholera patients. As in humans, V. cholerae mutants that do not produce cholera toxin (CT) and toxin-coregulated pilus (TCP) did not induce cholera-like disease in rabbits. CT induced extensive exocytosis of mucin from intestinal goblet cells, and wild-type V. cholerae was predominantly found in close association with mucin. Large aggregates of mucin-embedded V. cholerae were observed, both attached to the epithelium and floating within the diarrheal fluid. These findings suggest that CT-dependent mucin secretion significantly influences V. cholerae's association with the host intestine and its exit from the intestinal tract. Our model should facilitate identification and analyses of factors that may govern V. cholerae infection, survival, and transmission, such as mucin. In addition, our results using nontoxigenic V. cholerae suggest that infant rabbits will be useful for study of the reactogenicity of live attenuated-V. cholerae vaccines.

No MeSH data available.


Related in: MedlinePlus