Optimization and validation of a real-time polymerase chain reaction protocol for the diagnosis of human brucellosis

Zeybek H., Acikgoz Z., Dal T., Durmaz R.

Folia Microbiologica, cilt.65, sa.2, ss.353-361, 2020 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 65 Sayı: 2
  • Basım Tarihi: 2020
  • Doi Numarası: 10.1007/s12223-019-00731-1
  • Dergi Adı: Folia Microbiologica
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Agricultural & Environmental Science Database, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, CAB Abstracts, EMBASE, MEDLINE, Veterinary Science Database
  • Sayfa Sayıları: ss.353-361
  • Ankara Yıldırım Beyazıt Üniversitesi Adresli: Evet

Özet

Due to limitations in commercial diagnostic methods, this study aimed to develop a reliable real-time polymerase chain reaction (Rt-PCR) assay for early diagnosis of brucellosis. Optimization of the Rt-PCR method was performed on serum samples spiked by Brucella melitensis with different densities ranging from 101 to 108 colony-forming units (cfu)/mL; each density was prepared in ten samples. The limit of detection was investigated by using Thermo DNA extraction kit with Maxima SYBR Green Rt-PCR and two TaqMan probe-based Rt-PCR protocols performed by QuantiTect and TEMPase multiplex PCR master mixes in two thermal cyclers, which were Rotor-Gene and Bio-Rad. The validation of the optimized protocol was carried on 20 brucellosis-negative samples and 20 samples spiked with B. melitensis by using a combination of Thermo DNA extraction kit with TEMPase PCR master mix. SYBR Green Rt-PCR yielded positive results on all samples having ≥ 104 cfu/mL of B. melitensis in both thermal cyclers. Its limit of detection was 112 DNA copies per reaction. The positivity of both probe-based Rt-PCR protocols was 100% and 80% on the samples having 103 cfu/mL and 102 cfu/mL of B. melitensis, respectively. The limit of detection of probe-based protocols was defined as 4 DNA copies per reaction. The optimized Rt-PCR protocol showed high-level accuracy, precision, specificity, and sensitivity, each having a rate of 100%. The current study indicated that the TaqMan probe-based Rt-PCR protocol optimized and validated with serum samples can be reliably used for early diagnosis of brucellosis.