Rabies virus viability after short-term cryopreservation using cryoprotectant agents

Costa , Edmara ChavesTeixeira, Maria Fátima da SilvaAguiar, Tereza D’Ávila de FreitasRolim, Benedito NeilsonRomijn, Phyllis CatharinaRocha, Marcos Fábio Gadelha

Rabies virus cryopreservation has been succinctly described in the scientific literature. The major researches about viral conservation emphasize the rabies diagnosis in decomposed samples. For now few information has been available concerning the use of cryoprotectants for rabies virus cryopreservation. This study aimed at assessing the viability of rabies virus after freezing/thawing procedures and investigating the effect of different concentrations of dimethyl sulphoxide (DMSO), glycerol (GLY), polyethyleneglycol (PEG) and sucrose (SUC) on rabies virus cryopreservation. Virus viability was assessed by virus isolation based on mouse inoculation test, titration and immunofluorescent antibody assay before and after 30 days of freezing procedures. The rabies virus samples after being exposed to cryopreservation without adding a cryoprotectant, its viability showed to be lower than that observed in samples exposed to other treatments. After 30 days of freezing procedure, the viability of cryopreserved samples using DMSO, GLY or PEG was lower than that observedin fresh samples. In addition, the use of sucrose at 10 or 68 concentrations induced positive effects on the viral particles viability after a short-term cryopreservation.(AU)

1. Challenge virus standard