The Clinical Laboratory of Tianjin Chest Hospital, Tianjin, P.R. China.
Department of Medical Ultrasound, Tianjin Medical University General Hospital, Tianjin, P.R. China.
Expert Rev Mol Diagn. 2024 Jun;24(6):533-540. doi: 10.1080/14737159.2024.2369243. Epub 2024 Jun 19.
Cryptococcosis is a global invasive mycosis associated with significant morbidity and mortality. Cryptococcal antigen (CrAg) testing from serum and cerebrospinal fluid (CSF) has been regarded as a gold standard for early diagnosis. This study aimed to develop and validate a rapid and sensitive sandwich chemiluminescent magnetic microparticle immunoassay (CMIA) for quantitative detection of CrAg in sera.
CMIA is based on magnetic beads modified with capture antibodies and biotinylated antibodies and Streptavidin-polyHRP, where biotinylated antibodies functioned as the recognition element and Streptavidin-polyHRP as the signal component. Assay parameters were first optimized, and then assay performances were evaluated.
Under optimized conditions, the total runtime of the CMIA was 22 min. The assay had a wide linear range (2 -10,000 ng/mL) and high analytical sensitivity (0.24 ng/mL), together with acceptable reproducibility, accuracy, and stability. Besides, it exhibited no cross-reactivity with other pathogens. Importantly, the assay showed 92.91% (95% CI, 80.97-93.02%) overall qualitative agreement with a commercial ELISA kit in a retrospective cohort of 55 cases with confirmed cryptococcal infection, and 72 controls without evidence of invasive fungal disease (IFD).
These results demonstrated that the present study paved a novel strategy for reliable quantitative detection of CrAg in sera.
cryptococcosis 是一种全球性的侵袭性真菌病，与高发病率和死亡率相关。血清和脑脊液（CSF）中的 cryptococcal 抗原（CrAg）检测已被认为是早期诊断的金标准。本研究旨在开发和验证一种用于定量检测血清中 CrAg 的快速灵敏的夹心化学发光磁微粒免疫分析（CMIA）。
CMIA 基于磁珠修饰的捕获抗体和生物素化抗体以及 Streptavidin-polyHRP，其中生物素化抗体作为识别元件，Streptavidin-polyHRP 作为信号成分。首先优化了测定参数，然后评估了测定性能。
在优化条件下，CMIA 的总运行时间为 22 分钟。该测定具有宽线性范围（2-10000ng/mL）和高分析灵敏度（0.24ng/mL），同时具有可接受的重现性、准确性和稳定性。此外，它与其他病原体无交叉反应。重要的是，该测定在一个回顾性队列的 55 例确诊 cryptococcal 感染病例和 72 例无侵袭性真菌病（IFD）证据的对照中，与商业 ELISA 试剂盒的总体定性一致性为 92.91%（95%CI，80.97-93.02%）。
这些结果表明，本研究为血清中 CrAg 的可靠定量检测开辟了新的策略。
