Joint evaluation of type I Sabin strain poliovirus neurovirulence by two different assays

Objective To study the difference between the neurovirulence results of the same type Ⅰ Sabin strain poliovirus using mutant analysis by PCR and restriction enzyme cleavage (MAPREC) and monkey neurovirulence test (MNVT). Methods The MAPREC assay was used to detect the point mutation rate of the amino acids 480 and 525, key sites for the virulence of type Ⅰ Sabin strain poliovirus. The paraffin sections of the MNVT were analyzed to evaluate the neurovirulence of the same virus strain. Results The average mutation rate of 480 and 525 sites in MAPREC assay was 0.460%, which was lower than 1.288% of high mutant virus reference. The paraffin sections results of MNVT showed that the lesion score difference of effective monkeys was qualified. Conclusion The MAPREC result of the same batch of samples is consistent with the MNVT result. Key words: Poliovirus; Vaccines, attenuated; Neurovirulence; Sequence analysis, RNA; Animal experimentation