title: Attenuation of type A7 and A21 coxsackie viruses by transfection of cells with viral RNA.
abstract: Coxsackie viruses of types A7 and A21 were produced in HEp-2 cells and concentrated by precipitation with polyethylene glycol. The viral RNA was extracted by means of the hot phenol-SDS method and used for transfection of Hep-2 cells. Transfection was greatly enhanced by the addition of DEAE-dextran. 8 of 11 (72.7 per cent) coxsackie viruses obtained after 1 to 3 transfections were found to have drastically reduced pathogenicity in suckling mice in comparison to the corresponding viruses produced by infection. Attenuation was generally obtained after the first transfection and could be improved by further transfections in one experiment, only.
authors.forename: W
authors.initials: W
authors.lastname: Verhagen
authors.forename: S
authors.initials: S
authors.lastname: Matthei
mesh_terms: D000818:Animals; D000833:Animals, Suckling; D002294:Carcinoma, Squamous Cell; D002460:Cell Line; D003637:DEAE-Dextran / Q000494:pharmacology; D004770:Enterovirus / Q000235:genetics / Q000276:immunology / Q000472:pathogenicity*; D007822:Laryngeal Neoplasms; D051379:Mice; D009500:Neutralization Tests; D012367:RNA, Viral; D014162:Transfection; D014774:Virulence
chemical_list: D012367:RNA, Viral; D003637:DEAE-Dextran