Isolation of Rotavirus C from Bovine Feces by Spheroid Culture Method

Abstract

Spheroids are three-dimensional cell colonies, and spheroid culture enables cell culture in an environment that resembles an in vivo environment more closely than adhesion cell culture. In the field of veterinary medicine, there have been no reports on the application of spheroid culture for the isolation of viruses. We verified the possibility of using this culture technique for virus isolation by comparing the results obtained from the isolation of viruses in adherent culture and spheroid culture, using five bovine stool samples that tested positive for rotavirus C (RVC) based on the detection of a specific gene. As a result, RVC was successfully isolated from three of the five samples by spheroid culture method. In addition, it was possible to isolate the virus at a higher rate when it was inoculated before spheroid formation. Therefore, inoculation of the specimen before spheroid formation was considered important for implementing this method. There are only two cases of RVC isolation reported in Japan, and improvement of the virus isolation rate can be expected by using spheroid cultures. Moreover, this spheroid culture method can be beneficial for studying virus species that are difficult to isolate.