Comparison of Rotavirus RF Strain and HSV-۱ Titration by CCID۵۰% and Plaque Assays

Objective: Titration of viruses is important to determine the quantity of virus in vaccine development, master virus seed stock preparation, viral vector studies and virus replication. In this study, we compared the CCID۵۰% and plaque assay as a standard titration method for rotavirus (RF) and HSV-۱.   Methods: The MA۱۰۴ and Vero cells were inoculated by RF and HSV-۱ in ۶- and ۹۶-well plates. Following infection and adsorption, the optimal time for the cytopathic effect caused by the viruses was noted and the results compared. Results: The CPE (Cytopathic Effect) of RF was observed in less than ۱۸ hours, which increased until ۷۲ hours after inoculation. In HSV-۱, the CPE was observed ۲۴ and ۷۲ hours after inoculation. The virus titration in the plaque assay was monitored at ۹۶ hours post-infection for RF and at ۷۲ hours post-infection for HSV-۱. In both viruses the plaque titer method was lower than the CCID۵۰ method, since the results indicated that ۱ CCID۵۰% was equal to ۰.۷ PFU. Conclusion: The plaque assay is one of the most accurate methods for viral titration. For the plaque assay, individual lesions may be isolated, which the plaques can be counted. The CCID۵۰% method is not applicable for purification of homogenous viruses, nor is this technique reproducible.

کلیدواژه ها:

CCID۵۰% ، CCID۵۰% ، Plaque Assay ، Rotavirus ، HSV-۱ ، روش پلاک ، روتاویروس ، هرپس ویروس