Hacking J, Gwenin V V, Dacombe R J, Baird M S, Frimpong M, Phillips R O, Gwenin C D
School of Natural Sciences, Bangor University, Bangor, Gwynedd, Wales.
Liverpool School of Tropical Medicine, Liverpool, UK.
Public Health Action. 2023 Dec;13(4):173-178. doi: 10.5588/pha.23.0038. Epub 2023 Dec 7.
The diagnosis of Buruli ulcer (BU) is frequently made by experienced health workers in rural regions. This leads to long turnaround times to confirm the diagnosis as it requires specialised laboratory infrastructure to perform confirmatory testing.
Given the lack of success with protein antigens to detect BU in human sera, the aim of this study was to evaluate a range of single synthetic lipid antigens using an enzyme-linked immunosorbent assay (ELISA). The ELISA system used was initially developed to detect TB using single synthetic lipid antigens.
Thirty polymerase chain reaction (PCR) positive BU samples and 30 PCR-negative healthy contact samples collected from Asante Akim North and Ahafo Ano North Districts, Ghana, that are endemic for BU between 2013 and 2016 were used to evaluate the synthetic lipid antigen ELISA. A Quantikine ELISA was also conducted on a randomly blinded sub-set of 30 samples.
The synthetic lipid ELISA evaluated here outperforms all other ELISA tests using protein antigens to detect BU to date and has shown potential as a fast (2 h) test for BU which may be adapted for use at the point of care. A sensitivity of 63% and specificity of 80% was observed for 30 BU-positive and 30 BU-negative samples, with significantly reduced interleukin-8 (IL-8) levels in a subset of patients with BU.
A single lipid was shown for the first time to have the ability to distinguish between PCR-positive BU and negative sera using ELISA. The low lipid antibody load detected may be a result of immune suppression caused by the presence of mycolactone in patients with BU, given that levels of IL-8 were significantly reduced in patients with BU compared to the control serum samples.
布氏溃疡（BU）的诊断通常由农村地区经验丰富的卫生工作者进行。这导致确诊时间较长，因为需要专门的实验室基础设施来进行确诊检测。
鉴于使用蛋白质抗原检测人血清中布氏溃疡的效果不佳，本研究的目的是使用酶联免疫吸附测定（ELISA）评估一系列单一合成脂质抗原。所使用的ELISA系统最初是为使用单一合成脂质抗原检测结核病而开发的。
从2013年至2016年布氏溃疡流行的加纳阿桑特阿基姆北区和阿哈福阿诺北区收集了30份聚合酶链反应（PCR）阳性的布氏溃疡样本和30份PCR阴性的健康对照样本，用于评估合成脂质抗原ELISA。还对30个样本的随机盲选子集进行了定量ELISA检测。
此处评估的合成脂质ELISA在使用蛋白质抗原检测布氏溃疡方面优于目前所有其他ELISA检测，并且已显示出作为布氏溃疡快速（2小时）检测的潜力，该检测可能适用于即时检测。对于30份布氏溃疡阳性和30份布氏溃疡阴性样本，观察到灵敏度为63%，特异性为80%，布氏溃疡患者亚组中的白细胞介素-8（IL-8）水平显著降低。
首次证明单一脂质能够使用ELISA区分PCR阳性的布氏溃疡和阴性血清。检测到的低脂质抗体负荷可能是布氏溃疡患者中存在的分枝杆菌内酯引起免疫抑制的结果，因为与对照血清样本相比，布氏溃疡患者的IL-8水平显著降低。
