Project: Rapid detection of Mycobaterium ulcerans infection by recombinase polymerase amplification

Acronym	BU-RPA (Reference Number: TMA 2015 CDF - 979)
Duration	01/06/2017 - 31/05/2020
Project Topic	Buruli ulcer (BU) is a neglected tropical disease, principally in West African countries, that causes large disfiguring ulcers. It is caused by infection with Mycobacterium ulcerans (M. ulcerans) in the subcutaneous layer of the skin. There are no proven preventive strategies against BU, so early diagnosis and treatment is crucial to avoid physical disabilities that occur if not managed early. Polymerase chain reaction (PCR) for the IS2404 repeat sequence of M. ulcerans plasmid DNA is regarded as the gold standard for case confirmation due to its high sensitivity and specificity but its use is limited by high cost and the need for a sophisticated laboratory setup, not usually available in resource-poor endemic communities. The need to carry diagnostic samples to specialised laboratories for case confirmation results in delays in treating patients and high cost of case management. Thus research in developing a point of care diagnostic test is a major research priority. The purpose of my proposed research is to explore the potential of using recombinase polymerase amplification (RPA) as a tool for BU diagnosis. RPA has emerged as a novel isothermal technology for use in molecular diagnosis of infectious diseases. The key goals will be to: (1) To optimise an RPA assay for the diagnosis of Buruli ulcer. (2) Test its sensitivity and specificity in clinical samples by comparison with the PCR for IS2404 as gold standard. (3) To assess the feasibility and acceptability of using the technique in terms of its implementation in resourcelimited health facilities / laboratories by health staff (4) Explore and initiate development of a lateral flow RPA detection system My preliminary investigations in the laboratory have shown great promise using RPA to detect M. ulcerans DNA by targeting the IS2404 insertion sequence, the same target used in PCR diagnostics. Initial results have shown that we can accurately detect DNA from multiple strains of M. ulcerans (Mu1082, Mu5114, Mu912, and Mu560) but not from other mycobacteria (e.g. M. tuberculosis, M. chelonae, M. avium, M. marinum, M. celatum and M. vaccae) using this assay. Taking account of the preliminary laboratory development work and testing the practical application in the field, I predict that the project time frame will be 36 months. The expected output will be to develop a point of care RPA assay for the detection of M. ulcerans in clinical samples.
Network	EDCTP2
Call	Training and Mobility Awards: Career Development Fellowships

Project partner

Number	Name	Role	Country
1	Kwame Nkrumah University of Science and Technology	Coordinator	Ghana