Sensitive multiplex PCR assay to differentiate Lyme spirochetes and emerging pathogens Anaplasma phagocytophilum and Babesia microti

BMC Microbiology

Nikhat Parveen²  Salvatore AE Marras¹  Kamfai Chan² 

[1] Public Health Research Institute, 225 Warren Street, Newark, NJ 07103-3535, USA;Department of Microbiology and Molecular Genetics, Rutgers-New Jersey Medical School, 225 Warren Street, Newark, NJ 07103-3535, USA

关键词: Anaplasmosis;    Babesiosis;    Lyme disease;    Multiplex assay;    Molecular beacons;    Real-time PCR;    Tick-borne emerging pathogens;    Babesia microti;    Anaplasma phagocytophilum;    Borrelia burgdorferi;   

Others  :  1142289
DOI  :  10.1186/1471-2180-13-295

 received in 2013-09-06, accepted in 2013-12-12,  发布年份 2013

【 摘 要 】

Background

The infection with Borrelia burgdorferi can result in acute to chronic Lyme disease. In addition, coinfection with tick-borne pathogens, Babesia species and Anaplasma phagocytophilum has been increasing in endemic regions of the USA and Europe. The currently used serological diagnostic tests are often difficult to interpret and, moreover, antibodies against the pathogens persist for a long time making it difficult to confirm the cure of the disease. In addition, these tests cannot be used for diagnosis of early disease state before the adaptive immune response is established. Since nucleic acids of the pathogens do not persist after the cure, DNA-based diagnostic tests are becoming highly useful for detecting infectious diseases.

Results

In this study, we describe a real-time multiplex PCR assay to detect the presence of B. burgdorferi, B. microti and A. phagocytophilum simultaneously even when they are present in very low copy numbers. Interestingly, this quantitative PCR technique is also able to differentiate all three major Lyme spirochete species, B. burgdorferi, B. afzelii, and B. garinii by utilizing a post-PCR denaturation profile analysis and a single molecular beacon probe. This could be very useful for diagnosis and discrimination of various Lyme spirochetes in European countries where all three Lyme spirochete species are prevalent. As proof of the principle for patient samples, we detected the presence of low number of Lyme spirochetes spiked in the human blood using our assay. Finally, our multiplex assay can detect all three tick-borne pathogens in a sensitive and specific manner irrespective of the level of each pathogen present in the sample. We anticipate that this novel diagnostic method will be able to simultaneously diagnose early to chronic stages of Lyme disease, babesiosis and anaplasmosis using the patients’ blood samples.

Conclusion

Real-time quantitative PCR using specific primers and molecular beacon probes for the selected amplicon described in this study can detect three tick-borne pathogens simultaneously in an accurate manner.

【 授权许可】

   
2013 Chan et al.; licensee BioMed Central Ltd.

【 图 表 】

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