Lumazine synthase displayed poly-nanobodies for detection of soluble PD-L1 in human serum
10.3760/cma.j.cn121382-20211119-00304
- VernacularTitle:基于二氧四氢喋啶合酶多聚纳米抗体的血清中可溶性PD-L1蛋白检测方法
- Author:
Yuan XIE
1
;
Chang LIU
;
Xinlan XU
;
Xin ZHANG
;
Qianqian HU
;
Jiangwei LI
Author Information
1. 新疆大学生命科学与技术学院，新疆生物资源基因工程重点实验室，乌鲁木齐 830046
- Keywords:
Lumazine synthase;
Poly-nanobodies;
Sandwich ELISA;
Soluble PD-L1
- From:
International Journal of Biomedical Engineering
2022;45(3):213-219
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To established a method for the detection of soluble programmed death ligand 1 (PD-L1) protein in serum based on the poly nanoantibody of lumazine synthase(LS).Methods:A dual nanobody-based sandwich ELISA was established with a competitive ELISA to screen nanobodies recognizing different epitopes of PD-L1 as paired antibodies. To improve sensitivity, PD-L1 nanobody P3C8 and lumazine synthase(LS) were fused, and nanobodies were obtained in polymeric forms as sPD-L1 protein captures, so as to develop an LS-displayed polymeric nanobody-based sandwich ELISA (LSNbs-ELISA) method to detect sPD-L1.Results:Compared with the Nbs-ELISA method, the LSNbs-ELISA method is approximately 11-fold more sensitive for sPD-L1 detection. The limit of detections (LODs) of Nbs-ELISA and LSNbs-ELISA for sPD-L1 in serum were 2.87 ng/ml and 0.255 ng/ml, respectively. Both assays were highly specific for the detection of sPD-L1 and did not react with structure-related proteins PD-1, CD27, CD70, CD137, and CD147 when spiked into the human serum.Conclusions:The Nbs-ELISA and LSNbs-ELISA assays both have high sensitivity and specificity for detecting sPD-L1 in serum and could have potential clinical applications.
