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.