TGPVR21 MICE FOR TESTING TYPE-3 ORAL POLIOVIRUS VACCINES - ROLE OF CLINICAL OBSERVATION AND HISTOLOGICAL EXAMINATION

Transgenic mice susceptible to poliovirus (TgPVR mice) have been used to study poliovirus neurovirulence and attenuation. It was shown recen tly that mouse line TgPVR21 may be a suitable model to evaluate neurov irulence safety of oral poliovirus vaccine. It was important to determ ine whether TgPVR21 mice are sensitive enough to discriminate between type-3 reference and 'marginal' vaccines, i.e. those that failed the m onkey test while containing only slightly increased amounts of neurovi rulent revertants at position 472 of the viral genome as measured by a molecular assay MAPREC. Data presented here demonstrate that TgPVR21 mice are not less sensitive than monkeys in the detection of marginal vaccines. In contrast to the monkey neurovirulence test, which is base d on histological examination of the CNS, the TgPVR21 mouse neurovirul ence test revealed marginal vaccines by simple analysis of clinical si gns without requiring a laborious histological examination. Published by Elsevier Science Ltd.