title: Isolation and characterization of plaque-purified strains of Malacosoma disstria Nucleopolyhedrovirus.
abstract: Seven plaque-purified genotypic variants or strains, derived from a previously described field isolate of the Malacosoma disstria Nucleopolyhedrovirus (MadiNPV) from Alberta populations of forest tent caterpillar, were characterized based on distinctive restriction endonuclease fragment patterns. Two strains, MadiNPV-pp3 and MadiNPV-pp11, were selected for further characterization, as they represented strains producing high and low budded virus (BV) titres, respectively, in the M. disstria cell line UA-Md203. Analysis of restriction endonuclease fragment profiles indicated the genomes differed significantly in size, 133.8 +/- 2.4 kb for MadiNPV-pp3 and 118.1 +/- 3.5 kb for MadiNPV-pp11. These strains were characterized based on their BV production in three different cell lines derived from M. disstria haemocytes. Compared with MadiNPV-pp11, MadiNPV-pp3 produced two- to three-fold more BVs in UA-Md203 and 210 other cell lines; however, BV production was only marginally higher for MadiNPV-pp3 in the UA-Md221 cell line. Similarly, the yield of polyhedral inclusion bodies was significantly higher for MadiNPV-pp3 in UA-Md203 and 210 cell lines than for MadiNPV-pp11 but not in the UA-Md221 cell line. This data, although derived from a limited number of cell lines, suggested MadiNPV-pp3 may have a broader tissue tropism than MadiNPV-pp11.
authors.affiliation: Agriculture and Agri-Food Canada, Saskatoon Research Centre, Canada. erlandsonm@agr.gc.ca
authors.forename: Martin A
authors.initials: MA
authors.lastname: Erlandson
authors.forename: Doug
authors.initials: D
authors.lastname: Baldwin
authors.forename: Melissa
authors.initials: M
authors.lastname: Haveroen
authors.forename: B Andrew
authors.initials: BA
authors.lastname: Keddie
mesh_terms: D000818:Animals; D007915:Lepidoptera / Q000821:virology*; D017924:Nucleopolyhedroviruses / Q000145:classification / Q000302:isolation & purification* / Q000472:pathogenicity; D015183:Restriction Mapping / Q000379:methods; D010948:Viral Plaque Assay