This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Lu, S.
Right arrow Articles by Riley, L. W.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Lu, S.
Right arrow Articles by Riley, L. W.

 Previous Article  |  Next Article 

Infection and Immunity, November 1999, p. 5651-5657, Vol. 67, No. 11
0019-9567/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.

Analysis of Virulence of Clinical Isolates of Salmonella enteritidis In Vivo and In Vitro

Sangwei Lu,1 Amee R. Manges,1 Yisheng Xu,2 Ferric C. Fang,2 and Lee W. Riley1,*

Program in Infectious Diseases and Immunity, School of Public Health, University of California at Berkeley, Berkeley, California,1 and Department of Medicine, Division of Infectious Diseases, University of Colorado Health Sciences Center, Denver, Colorado2

Received 17 May 1999/Returned for modification 5 August 1999/Accepted 9 August 1999

Salmonella enterica serotype Enteritidis (S. enteritidis) is a major food-borne pathogen, and its incidence among all Salmonella serotypes has increased dramatically in the last two decades. To study the virulence characteristics of clinical isolates of S. enteritidis, we determined the 50% lethal doses (LD50) in mice of isolates of two major phage types (4 and 8). Isolates of both phage types showed a wide range of LD50 after oral inoculation, varying from under 102 organisms to over 108 organisms. No significant difference in LD50 was observed between the phage types. These observations indicated that clinical isolates of S. enteritidis are highly heterogeneous in their ability to cause death in mice. We compared the LD50s of these isolates to the results observed from in vitro pathogenicity assays. We also analyzed these isolates for recognized Salmonella virulence loci (spv, sodCI, sopE, and sef). The in vitro phenotypes of the isolates showed no obvious correlation with their LD50 in any given assay, and the virulence genes tested were present in all isolates. However, the isolate with the lowest LD50 (isolate 97A 2472) was resistant to acidified sodium nitrite (ASN). Moreover, the most acid-susceptible, macrophage-susceptible, and ASN-susceptible isolates were attenuated for virulence in mice. These results, based on extensive analysis of clinical isolates of S. enteritidis, demonstrate the complex nature of Salmonella pathogenesis in mice. Our results also indicate the limitation of in vitro assays in predicting in vivo virulence.


* Corresponding author. Mailing address: 140 Warren Hall, School of Public Health, University of California at Berkeley, Berkeley, CA 94720. Phone: (510) 642-9200. Fax: (510) 642-6350. E-mail: lwriley{at}uclink4.berkeley.edu.


Infection and Immunity, November 1999, p. 5651-5657, Vol. 67, No. 11
0019-9567/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.



This article has been cited by other articles:

  • Su, J., Gong, H., Lai, J., Main, A., Lu, S. (2009). The Potassium Transporter Trk and External Potassium Modulate Salmonella enterica Protein Secretion and Virulence. Infect. Immun. 77: 667-675 [Abstract] [Full Text]  
  • Foley, S. L., Lynne, A. M. (2008). Food animal-associated Salmonella challenges: Pathogenicity and antimicrobial resistance. J ANIM SCI 86: E173-E187 [Abstract] [Full Text]  
  • Heithoff, D. M., Shimp, W. R., Lau, P. W., Badie, G., Enioutina, E. Y., Daynes, R. A., Byrne, B. A., House, J. K., Mahan, M. J. (2008). Human Salmonella Clinical Isolates Distinct from Those of Animal Origin. Appl. Environ. Microbiol. 74: 1757-1766 [Abstract] [Full Text]  
  • Ghebremicael, S. B., Hasenstein, J. R., Lamont, S. J. (2008). Association of Interleukin-10 Cluster Genes and Salmonella Response in the Chicken. Poult. Sci. 87: 22-26 [Abstract] [Full Text]  
  • Clavijo, R. I., Loui, C., Andersen, G. L., Riley, L. W., Lu, S. (2006). Identification of Genes Associated with Survival of Salmonella enterica Serovar Enteritidis in Chicken Egg Albumen. Appl. Environ. Microbiol. 72: 1055-1064 [Abstract] [Full Text]  
  • Lu, S., Killoran, P. B., Riley, L. W. (2003). Association of Salmonella enterica Serovar Enteritidis YafD with Resistance to Chicken Egg Albumen. Infect. Immun. 71: 6734-6741 [Abstract] [Full Text]  
  • Fernandez, J., Fica, A., Ebensperger, G., Calfullan, H., Prat, S., Fernandez, A., Alexandre, M., Heitmann, I. (2003). Analysis of Molecular Epidemiology of Chilean Salmonella enterica Serotype Enteritidis Isolates by Pulsed-Field Gel Electrophoresis and Bacteriophage Typing. J. Clin. Microbiol. 41: 1617-1622 [Abstract] [Full Text]  
  • Iankov, I. D., Petrov, D. P., Mladenov, I. V., Haralambieva, I. H., Mitov, I. G. (2002). Lipopolysaccharide-Specific but Not Anti-Flagellar Immunoglobulin A Monoclonal Antibodies Prevent Salmonella enterica Serotype Enteritidis Invasion and Replication within HEp-2 Cell Monolayers. Infect. Immun. 70: 1615-1618 [Abstract] [Full Text]  
  • Lu, S., Killoran, P. B., Fang, F. C., Riley, L. W. (2002). The Global Regulator ArcA Controls Resistance to Reactive Nitrogen and Oxygen Intermediates in Salmonella enterica Serovar Enteritidis. Infect. Immun. 70: 451-461 [Abstract] [Full Text]  
  • Allen, C. A., Fedorka-Cray, P. J., Vazquez-Torres, A., Suyemoto, M., Altier, C., Ryder, L. R., Fang, F. C., Libby, S. J. (2001). In Vitro and In Vivo Assessment of Salmonella enterica Serovar Typhimurium DT104 Virulence. Infect. Immun. 69: 4673-4677 [Abstract] [Full Text]