[Establishment of a chemiluminescent immunoassay(CLIA) and its application]

Objective To establish a chemiluminescent immunoassay(CLIA) for the detection of soluble CD100 (sCD100) and evaluate its preliminary clinical application for the detection of sCD100 in clinical cerebrospinal fluid samples. Methods Ascites were prepared using two hybridomas secreting monoclonal antibody (mAb) to CD100, and the antibodies were purified. Based on sandwich ELISA, the experiment conditions were optimized and the CLIA for detecting sCD100 was established. The sensitivity and stability of CLIA were evaluated. The level of sCD100 in cerebrospinal fluid samples of patients (n=18) was detected. Results CLIA exhibited high performance within a dynamic range 0.098-12.5 ng/mL, and the limit of detection (LOD) was 0.12 ng/mL. The intra-assay coefficient variations (CV) were between 3.8%-6.6% and inter-assay CV were 6.2%-14.1%. Using CLIA, we examined the level of sCD100 in cerebrospinal fluid of viral encephalitis patients. The results showed the level of sCD100 in the patients were higher than that in normal controls. Two cases of them were 9.4 and 13.8 times higher than the normal mean value of control group. Conclusion A rapid, sensitive and stable CLIA for detecting sCD100 has been successfully established, which can be used for the quantitative detection of trace sCD100 in cerebrospinal fluid samples.