This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Doyle, C. K. Articles by McBride, J. W. Search for Related Content PubMed PubMed Citation Articles by Doyle, C. K. Articles by McBride, J. W.

JMD 2005, Vol. 7, No. 4
Copyright © 2005 American Society for Investigative Pathology & Association for Molecular Pathology

Detection of Medically Important Ehrlichia by Quantitative Multicolor TaqMan Real-Time Polymerase Chain Reaction of the dsb Gene

C. Kuyler Doyle^*, Marcelo B. Labruna, Edward B. Breitschwerdt, Yi-Wei Tang^||, Richard E. Corstvet^||, Barbara C. Hegarty, Karen C. Bloch^**, Ping Li, David H. Walker^* and Jere W. McBride^*

From the Departments of Pathology * and Microbiology and Immunology, Sealy Center for Vaccine Development, and Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, Texas; the Departmento de Medicina Veterinaria Preventiva e Saude Animal, Faculdade de Medicina Veterinaria e Zootecnia, University of Sao Paulo, Sao, Paulo, Brazil; the Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina; the Departments of Medicine, Pathology, ^|| and Preventive Medicine, ** Vanderbilt University Medical Center, Nashville, Tennessee; and the Department of Pathobiological Sciences, ^|| School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana

Ehrlichia species are the etiological agents of emerging and life-threatening tick-borne human zoonoses, in addition to causing serious and fatal infections in companion animals and livestock. We developed the first tricolor TaqMan real-time polymerase chain reaction assay capable of simultaneously detecting and discriminating medically important ehrlichiae in a single reaction. Analytical sensitivity of 50 copies per reaction was attained with templates from Ehrlichia chaffeensis, Ehrlichia ewingii, and Ehrlichia canis by amplifying the genus-specific disulfide bond formation protein gene (dsb). Ehrlichia genus-specific dsb primers amplified DNA from all known Ehrlichia species but not from other rickettsial organisms including Anaplasma platys, Anaplasma phagocytophilum, Rickettsia conorii, or Rickettsia typhi. High species specificity was attained as each species-specific TaqMan probe (E. chaffeensis, E. ewingii, and E. canis) identified homologous templates but did not cross-hybridize with heterologous Ehrlichia templates at concentrations as high as 10⁸ copies. Identification of E. chaffeensis, E. ewingii, and E. canis from natural and experimental infections, previously confirmed by polymerase chain reaction and serological or microscopic evidence, demonstrated the comparable specificity and sensitivity of the dsb real-time assay. This assay provides a powerful tool for prospective medical diagnosis for human and canine ehrlichioses and for ecologic and epidemiological studies involving arthropod and mammalian hosts.

This article has been cited by other articles:

				J. Dong, J. P. Olano, J. W. McBride, and D. H. Walker Emerging Pathogens: Challenges and Successes of Molecular Diagnostics J. Mol. Diagn., May 1, 2008; 10(3): 185 - 197. [Abstract] [Full Text] [PDF]