title: Partial change of the ts-phenotype of cold-adapted influenza virus strain grown in canine kidney cells in the presence of trypsin.
abstract: The cold-adapted temperature-sensitive (ts) influenza virus strain A/Leningrad/134/17/57 (H2N2) multiplied well at 32 degrees C (optimal temperature); lower titres of infectious virus were obtained in developing chick embryos at 40 degrees C. In a canine kidney (MDCK) cell line and in primary calf kidney (CK) cells an increased reproduction of the virus was found at 40 degrees C especially in the presence of trypsin. The ratios of virus titres obtained at optimal versus higher temperatures (RCT40) were by 1,000 times lower than those found in chick embryos. Polyacrylamide gel electrophoresis revealed a comparable synthesis of the cold-adapted influenza virus strain polypeptides HA, NP, M and NS in MDCK cells, regardless whether they were incubated at optimal or non-permissive temperatures.
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D002417:Cattle; D002460:Cell Line; D002478:Cells, Cultured; D002642:Chick Embryo; D003080:Cold Temperature; D004285:Dogs; D009980:Influenza A virus / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D007668:Kidney; D014357:Trypsin / Q000494:pharmacology*; D014764:Viral Proteins / Q000096:biosynthesis; D014779:Virus Replication / Q000187:drug effects
chemical_list: D014764:Viral Proteins; D014357:Trypsin