Skip to main content
PMC home page
Journal of Clinical Microbiology logoLink to Journal of Clinical Microbiology
. 1995 Jul;33(7):1704–1711. doi: 10.1128/jcm.33.7.1704-1711.1995

Isolation and characterization of a new strain of Ehrlichia chaffeensis from a patient with nearly fatal monocytic ehrlichiosis.

J S Dumler 1, S M Chen 1, K Asanovich 1, E Trigiani 1, V L Popov 1, D H Walker 1
PMCID: PMC228253  PMID: 7665632

Abstract

Ehrlichia chaffeensis is the causative agent of human monocytic ehrlichiosis, a disease that ranges in severity from asymptomatic infection to death. Only one isolate of E. chaffeensis has been made, the Arkansas strain, upon which all characterizations of the agent of human monocytic ehrlichiosis have been based. We report the isolation and characterization of a new strain of E. chaffeensis, the 91HE17 strain, which was cultivated from a patient with a nearly fatal illness. The new isolate grows best in culture with careful control of pH. The two isolates are nearly identical as determined by light and electron microscopy and have significant antigenic identity in fluorescent-antibody and immunoblot assays using polyclonal antisera and the E. chaffeensis-specific monoclonal antibody 1A9. Isolate 91HE17 had 99.9% nucleotide sequence identity with the Arkansas strain in the 16S rRNA gene. Parts of the Escherichia coli GroE operon homologs had identical restriction enzyme digestion patterns, and a 425-bp region of the GroEL gene had at least 99.8% sequence identity between the E. chaffeensis Arkansas and 91HE17 strains. Isolate 91HE17 lacked an epitope identified in E. chaffeensis Arkansas by the monoclonal antibody 6A1. This new E. chaffeensis isolate is very similar to the Arkansas strain and provides the opportunity to substantiate the existence of diversity among ehrlichiae which infect humans. Specific factors which differ among strains may then be compared to assess their potential contributions toward cellular pathogenicity and ultimately toward the development of disease in humans.

Full Text

The Full Text of this article is available as a PDF (2.2 MB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Anderson B. E., Dawson J. E., Jones D. C., Wilson K. H. Ehrlichia chaffeensis, a new species associated with human ehrlichiosis. J Clin Microbiol. 1991 Dec;29(12):2838–2842. doi: 10.1128/jcm.29.12.2838-2842.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Anderson B. E., Sumner J. W., Dawson J. E., Tzianabos T., Greene C. R., Olson J. G., Fishbein D. B., Olsen-Rasmussen M., Holloway B. P., George E. H. Detection of the etiologic agent of human ehrlichiosis by polymerase chain reaction. J Clin Microbiol. 1992 Apr;30(4):775–780. doi: 10.1128/jcm.30.4.775-780.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Brouqui P., Birg M. L., Raoult D. Cytopathic effect, plaque formation, and lysis of Ehrlichia chaffeensis grown on continuous cell lines. Infect Immun. 1994 Feb;62(2):405–411. doi: 10.1128/iai.62.2.405-411.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Brouqui P., Dumler J. S., Raoult D., Walker D. H. Antigenic characterization of ehrlichiae: protein immunoblotting of Ehrlichia canis, Ehrlichia sennetsu, and Ehrlichia risticii. J Clin Microbiol. 1992 May;30(5):1062–1066. doi: 10.1128/jcm.30.5.1062-1066.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Chen S. M., Dumler J. S., Bakken J. S., Walker D. H. Identification of a granulocytotropic Ehrlichia species as the etiologic agent of human disease. J Clin Microbiol. 1994 Mar;32(3):589–595. doi: 10.1128/jcm.32.3.589-595.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Chen S. M., Dumler J. S., Feng H. M., Walker D. H. Identification of the antigenic constituents of Ehrlichia chaffeensis. Am J Trop Med Hyg. 1994 Jan;50(1):52–58. [PubMed] [Google Scholar]
  7. Chen S. M., Popov V. L., Feng H. M., Wen J., Walker D. H. Cultivation of Ehrlichia chaffeensis in mouse embryo, Vero, BGM, and L929 cells and study of Ehrlichia-induced cytopathic effect and plaque formation. Infect Immun. 1995 Feb;63(2):647–655. doi: 10.1128/iai.63.2.647-655.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Dawson J. E., Anderson B. E., Fishbein D. B., Sanchez J. L., Goldsmith C. S., Wilson K. H., Duntley C. W. Isolation and characterization of an Ehrlichia sp. from a patient diagnosed with human ehrlichiosis. J Clin Microbiol. 1991 Dec;29(12):2741–2745. doi: 10.1128/jcm.29.12.2741-2745.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Dawson J. E., Candal F. J., George V. G., Ades E. W. Human endothelial cells as an alternative to DH82 cells for isolation of Ehrlichia chaffeensis, E. canis, and Rickettsia rickettsii. Pathobiology. 1993;61(5-6):293–296. doi: 10.1159/000163808. [DOI] [PubMed] [Google Scholar]
  10. Dumler J. S., Dawson J. E., Walker D. H. Human ehrlichiosis: hematopathology and immunohistologic detection of Ehrlichia chaffeensis. Hum Pathol. 1993 Apr;24(4):391–396. doi: 10.1016/0046-8177(93)90087-w. [DOI] [PubMed] [Google Scholar]
  11. Dumler J. S., Sutker W. L., Walker D. H. Persistent infection with Ehrlichia chaffeensis. Clin Infect Dis. 1993 Nov;17(5):903–905. doi: 10.1093/clinids/17.5.903. [DOI] [PubMed] [Google Scholar]
  12. Dunn B. E., Monson T. P., Dumler J. S., Morris C. C., Westbrook A. B., Duncan J. L., Dawson J. E., Sims K. G., Anderson B. E. Identification of Ehrlichia chaffeensis morulae in cerebrospinal fluid mononuclear cells. J Clin Microbiol. 1992 Aug;30(8):2207–2210. doi: 10.1128/jcm.30.8.2207-2210.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Everett E. D., Evans K. A., Henry R. B., McDonald G. Human ehrlichiosis in adults after tick exposure. Diagnosis using polymerase chain reaction. Ann Intern Med. 1994 May 1;120(9):730–735. doi: 10.7326/0003-4819-120-9-199405010-00002. [DOI] [PubMed] [Google Scholar]
  14. Fichtenbaum C. J., Peterson L. R., Weil G. J. Ehrlichiosis presenting as a life-threatening illness with features of the toxic shock syndrome. Am J Med. 1993 Oct;95(4):351–357. doi: 10.1016/0002-9343(93)90302-6. [DOI] [PubMed] [Google Scholar]
  15. Fishbein D. B., Dawson J. E., Robinson L. E. Human ehrlichiosis in the United States, 1985 to 1990. Ann Intern Med. 1994 May 1;120(9):736–743. doi: 10.7326/0003-4819-120-9-199405010-00003. [DOI] [PubMed] [Google Scholar]
  16. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  17. Maeda K., Markowitz N., Hawley R. C., Ristic M., Cox D., McDade J. E. Human infection with Ehrlichia canis, a leukocytic rickettsia. N Engl J Med. 1987 Apr 2;316(14):853–856. doi: 10.1056/NEJM198704023161406. [DOI] [PubMed] [Google Scholar]
  18. Meier A., Persing D. H., Finken M., Böttger E. C. Elimination of contaminating DNA within polymerase chain reaction reagents: implications for a general approach to detection of uncultured pathogens. J Clin Microbiol. 1993 Mar;31(3):646–652. doi: 10.1128/jcm.31.3.646-652.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Petersen L. R., Sawyer L. A., Fishbein D. B., Kelley P. W., Thomas R. J., Magnarelli L. A., Redus M., Dawson J. E. An outbreak of ehrlichiosis in members of an Army Reserve unit exposed to ticks. J Infect Dis. 1989 Mar;159(3):562–568. doi: 10.1093/infdis/159.3.562. [DOI] [PubMed] [Google Scholar]
  20. Rikihisa Y. The tribe Ehrlichieae and ehrlichial diseases. Clin Microbiol Rev. 1991 Jul;4(3):286–308. doi: 10.1128/cmr.4.3.286. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Sumner J. W., Sims K. G., Jones D. C., Anderson B. E. Ehrlichia chaffeensis expresses an immunoreactive protein homologous to the Escherichia coli GroEL protein. Infect Immun. 1993 Aug;61(8):3536–3539. doi: 10.1128/iai.61.8.3536-3539.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Towbin H., Staehelin T., Gordon J. Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications. Proc Natl Acad Sci U S A. 1979 Sep;76(9):4350–4354. doi: 10.1073/pnas.76.9.4350. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Walker D. H., Dumler J. S. Emerging and reemerging rickettsial diseases. N Engl J Med. 1994 Dec 15;331(24):1651–1652. doi: 10.1056/NEJM199412153312410. [DOI] [PubMed] [Google Scholar]
  24. Wilson K. H., Blitchington R. B., Greene R. C. Amplification of bacterial 16S ribosomal DNA with polymerase chain reaction. J Clin Microbiol. 1990 Sep;28(9):1942–1946. doi: 10.1128/jcm.28.9.1942-1946.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Yu X., Brouqui P., Dumler J. S., Raoult D. Detection of Ehrlichia chaffeensis in human tissue by using a species-specific monoclonal antibody. J Clin Microbiol. 1993 Dec;31(12):3284–3288. doi: 10.1128/jcm.31.12.3284-3288.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Journal of Clinical Microbiology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES