Development of an interferon-γ release assay (IGRA) for detection of Brucella abortus and clinical diagnosis of brucellosis

  • Yu Feng Shandong Agricultural University, Taian, Shandong, China
  • Liangquan Zhu China Institute of Veterinary Drug Control, Beijing, China
  • Xiaowei Peng China Institute of Veterinary Drug Control, Beijing, China
  • Hui Jiang China Institute of Veterinary Drug Control, Beijing, China
  • Ge Zhang China Institute of Veterinary Drug Control, Beijing, China
  • Youxiang Diao China Institute of Veterinary Drug Control, Beijing, China
  • Jiabo Ding China Institute of Veterinary Drug Control, Beijing, China
Keywords: Brucella, , IGRA, diagnosis, brucellosis, IFN-γ, diagnostics

Abstract

Introduction: Brucellosis, caused by Brucella abortus (B. abortus), is an important zoonosis posing a great risk to both livestock and humans. Currently, most assays for clinical diagnosis of brucellosis have been developed based on serological principles; however, these assays have a number of limitations and disadvantages.

Methodology: To address this concern, the aim of this study was to develop a gamma interferon (IFN-γ) release assay (IGRA) for the diagnosis of brucellosis. Towards this end, the stimulating effect induced by different somatic antigens of B. abortus on the secretion of IFN-γ was evaluated.

Results: The best antigen candidate, B. abortus strain 2308, able to induce high levels of IFN-γ expression in peripheral blood (PB) cells from cattle, was used for the development of the IGRA. The optimal concentration for stimulation was determined as 1.0×107 CFU/mL. This study demonstrated that IFN-γ was detectable on day 5 post infection (p.i.) and peaked on day 14 p.i.. Finally, the IGRA developed was used for detection of B. abortus in clinical samples, and a higher level of IFN-γ was detected in Brucella-infected samples compared to vaccination samples and negative controls.

Conclusions: The optimal somatic antigen for B. abortus was identified and used to establish a robust IGRA. The IGRA developed is suitable for clinical diagnosis of brucellosis, especially in the early stages of infection.

Author Biographies

Yu Feng, Shandong Agricultural University, Taian, Shandong, China

College of Animal Science and Veterinary Medicine

Youxiang Diao, China Institute of Veterinary Drug Control, Beijing, China

College of Animal Science and Veterinary Medicine

Published
2017-12-10
How to Cite
1.
Feng Y, Zhu L, Peng X, Jiang H, Zhang G, Diao Y, Ding J (2017) Development of an interferon-γ release assay (IGRA) for detection of Brucella abortus and clinical diagnosis of brucellosis. J Infect Dev Ctries 11:847-853. doi: 10.3855/jidc.9265
Section
Original Articles