Application of 4-parameter model and parallel line assay in biological test statistics for antigens of viral vaccines

Objective To compare 4-parameter model with parallel line assay method in the application in biological test statistics for antigens of Sabin inactivated poliovirus vaccine (sIPV) and enterovirus 71 (EV71). Methods The 4-parameter model and parallel line assay were methodologically validated using the detection data of sIPV-D antigen and EV71 antigen. Then, both methods were used to calculate the detection result of samples with different antigen content. Results The 4-parameter model was fit for sIPV-D antigen detection data (coefficient of determination 0.998, residual value ≤0.059), and parallel line analysis was reliable (regression: reference F=727.49, P 0.05). For EV71 antigen, 4-parameter model was appropriate (coefficient of determination 1.000, residual value≤0.025), and parallel line analysis was reliable (regression: reference F=126.63, P 0.05). There was no significant difference between the calculation results of two methods for different antigen content of sIPV and EV71 (t=0.248-1.023, all P>0.05). Conclusion Both 4-parameter model and parallel line assay can be applied in the ELISA detection system of sIPV-D and EV71 antigens. Key words: Models, statistical; Viral vaccines; Antigen, viral; Enzyme-linked immunosorbent assay