Year-end Sale % OFF 
Abstract
BackgroundField-applicable tests detecting asymptomatic Mycobacterium leprae (M. leprae) infection or predicting progression to leprosy, are urgently required. Since the outcome of M. leprae infection is determined by cellular- and humoral immunity, we aim to develop diagnostic tests detecting pro-/anti-inflammatory and regulatory cytokines as well as antibodies against M. leprae. Previously, we developed lateral flow assays (LFA) for detection of cytokines and anti-PGL-I antibodies. Here we evaluate progress of newly developed LFAs for applications in resource-poor settings.MethodsThe combined diagnostic value of IP-10, IL-10 and anti-PGL-I antibodies was tested using M. leprae-stimulated blood of leprosy patients and endemic controls (EC). For reduction of the overall test-to-result time the minimal whole blood assay time required to detect distinctive responses was investigated. To accommodate LFAs for field settings, dry-format LFAs for IP-10 and anti-PGL-I antibodies were developed allowing storage and shipment at ambient temperatures. Additionally, a multiplex LFA-format was applied for simultaneous detection of anti-PGL-I antibodies and IP-10. For improved sensitivity and quantitation upconverting phosphor (UCP) reporter technology was applied in all LFAs.ResultsSingle and multiplex UCP-LFAs correlated well with ELISAs. The performance of dry reagent assays and portable, lightweight UCP-LF strip readers indicated excellent field-robustness. Notably, detection of IP-10 levels in stimulated samples allowed a reduction of the whole blood assay time from 24 h to 6 h. Moreover, IP-10/IL-10 ratios in unstimulated plasma differed significantly between patients and EC, indicating the feasibility to identify M. leprae infection in endemic areas.ConclusionsDry-format UCP-LFAs are low-tech, robust assays allowing detection of relevant cytokines and antibodies in response to M. leprae in the field. The high levels of IP-10 and the required shorter whole blood assay time, render this cytokine useful to discriminate between leprosy patients and EC.
Highlights
Leprosy, a curable infectious disease caused by Mycobacterium leprae (M. leprae) that affects the skin and peripheral nerves, is one of the six diseases considered by the WHO as a major threat in developing countries [1]
We developed lateral flow assays (LFA) for detection of pro-inflammatory (IP-10) vs. anti-inflammatory/regulatory (IL-10) cellular immunity as well as antibodies against M. leprae and evaluated these in a field setting in Ethiopia using lightweight, portable readers
To evaluate the combined diagnostic value of IL-10, induced protein 10 (IP-10) and IFN-c, we first determined their concentrations by ELISAs in 24 h Whole blood assays (WBA) of Ethiopian leprosy patients (9 BL, 2 BT) and endemic controls (EC)
Summary
A curable infectious disease caused by Mycobacterium leprae (M. leprae) that affects the skin and peripheral nerves, is one of the six diseases considered by the WHO as a major threat in developing countries [1]. Early detection of M. leprae infection, followed by effective interventions, is considered vital to interrupt transmission as highlighted by the WHO 2011–2015 global strategy [3]. Despite this pressing need, field-friendly tests that detect asymptomatic M. leprae infection are lacking, nor are there any biomarkers known that predict progression to disease in infected individuals. Field-applicable tests detecting asymptomatic Mycobacterium leprae (M. leprae) infection or predicting progression to leprosy, are urgently required. Since the outcome of M. leprae infection is determined by cellular- and humoral immunity, we aim to develop diagnostic tests detecting pro-/anti-inflammatory and regulatory cytokines as well as antibodies against M. leprae. We evaluate progress of newly developed LFAs for applications in resource-poor settings
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
