title: Application of a focus formation assay for detection and titration of porcine epidemic diarrhea virus.
abstract: A focus formation assay (FFA) for detection and titration of porcine epidemic diarrhea virus (PEDV) in a micro-culture system using Vero cells and PAP staining technique was evaluated. A linear correlation between the virus dilution and virus titer determined by FFA was observed between the range of 10 and 30 foci per well. Comparative analysis between FFA and plaque assay showed no significant difference in estimating the titer of cell adapted PEDV. However, the culture time required for detecting the virus was considerably shorter for FFA. In addition, FFA had higher sensitivity for detecting field isolates of PEDV as well as positive identification of the virus with the antibody specific reaction. A broader range of dilutions and number of replicates may be used for titration. A FFA may be applied as an alternative method for detection and titration of PEDV.
authors.affiliation: College of Veterinary Medicine, Chungnam National University, 220 Gung-Dong, Yuseong-Gu, Daejeon 305-764, Republic of Korea.
authors.forename: Deu John M
authors.initials: DJ
authors.lastname: Cruz
authors.forename: Hyun-Jin
authors.initials: HJ
authors.lastname: Shin
mesh_terms: D000818:Animals; D001681:Biological Assay / Q000379:methods*; D002522:Chlorocebus aethiops; D018352:Coronavirus Infections / Q000662:veterinary / Q000821:virology; D053485:Porcine epidemic diarrhea virus / Q000254:growth & development / Q000302:isolation & purification*; D013552:Swine; D013553:Swine Diseases / Q000821:virology; D014709:Vero Cells; D010948:Viral Plaque Assay