Applicability of biosensor technologies in the detection of Coxiella burnetii infection in clinical samples

Abstract

Q fever is a zooantroponoze distributed worldwide; it is caused by obligate intracellular bacterium Coxiella burnetii. Q fever is considered challenging for diagnosis and treatment. Clinical manifestations can vary among patients, which makes differential diagnosis difficult. In addition, in animals, the infection often remains latent, thus, creating a risk of uncontrolled dissemination and transmission to humans. Hence, the need for rapid and accurate identification of the pathogen to take timely and adequate therapeutic and prophylactic measures, including on-site testing. Current strategies for the detection of C. burnetii are molecular assays, e.g. polymerase chain reaction (PCR) or next-generation sequencing (NGS), and traditional serological tests. The conventional pathogen detection methods have serious limitations that make them not suitable for on-site analysis, as it requires level three biosafety laboratory conditions for cultivation in eukaryotic cell culture and poses significant health risks. In this review, we highlight the problems related to the application of biosensors in the detection of C. burnetii infection and their place among the standard diagnostic methods, given the potential of biosensors to provide rapid and quantitative diagnosis. We consider the applicability of surface plasmon resonance (SPR)-based biosensors for C. burnetii detection. The elaboration of an SPR biochip with an immobilized structural C. burnetii protein as a recognition molecule is described. The SPR assay is based on the binding reaction ‘infectious structural protein – anti-C. burnetii antibodies’. We discuss our preliminary results addressing their application in C. burnetii detection.

Keywords:

• Biosensors
• Q-fever
• laboratory diagnostics
• surface plasmon resonance (SPR) assay

Author contributions

PGK and GD, conceptualized and designed the study, wrote the original draft, reviewed and supervised the manuscript; contributed to funding; KS, TV and SK contributed to the study design, experimental studies, interpretation of data and contributed to funding acquisition; PF contributed to manuscript review and editing the data analysis. MB and IT contributed to the clinical studies, manuscript editing, literature research and contributed to funding acquisition. All authors have read and approved the final version of the manuscript and agree to be equally accountable for the integrity of the entire study.

Disclosure statement

The authors declare no conflict of interest.

Data availability statement

The data that support the findings from this study are available from the corresponding author [PGK] upon reasonable request.

Additional information

Funding

This work was supported by the Bulgarian National Science Fund under Grant number KP-06-N33/3, from 13 December 2019, entitled: ‘Molecular-genetic identification and creation of an archive genomic bank of the circulating human and animal C. burnetii genotypes and determination of their role as particularly dangerous infectious agents causing epidemiological outbreaks on the territory of Bulgaria’ and by the Bulgarian Ministry of Education and Science (MES) in the frames of Bulgarian National Recovery and Resilience Plan, Component ‘Innovative Bulgaria’, the Project № BG-RRP-2.004-0006-C02 ‘Development of research and innovation at Trakia University in service of health and sustainable well-being’.