title: [Study of biological properties of cold-adapted reassortant strain of influenza virus subtype H7N3].
abstract: For the development of live attenuated influenza vaccine (LAIV) against influenza virus strains with pandemic potential, method of classic genetic reassortment of donor of attenuation A/Leningrad/134/17/57 (H2N2) [Len/17] with avian apathogenic influenza viruses of different subtypes was used. Strain with genome formula 6:2, which contains HA and NA genes from avian apathogenic virus A/wild duck/Netherlands/12/00 (H7N3) [N7N3-wt] and 6 other genes--from Len/17, was studied. Reassortant strain A/17/ wild duck/Netherlands/00/84 (H7N3) [Lenl7/ H7] exhibited ts- and ca- phenotype specific for cold-adapted strains. Reassortant was identical on antigenic profile to parent avian virus H7N3-wt. Like cold-adapted donor strain Len/17, Len17/H7 was attenuated for chickens, whereas wild-type parent strain was lethal in 60% of birds after its intravenous challenge. Reassortant strain Len17/H7 was attenuated during intranasal inoculation of 6 EID50 to white mice, which was confirmed by absence of its isolation from the lungs, actively reproduced on nasal mucosa and stimulated specific systemic and local antibody response.
authors.forename: Iu A
authors.initials: IuA
authors.lastname: Desheva
authors.forename: T A
authors.initials: TA
authors.lastname: Smolonogina
authors.forename: M V
authors.initials: MV
authors.lastname: Sergeeva
authors.forename: A R
authors.initials: AR
authors.lastname: Rekstin
authors.forename: D
authors.initials: D
authors.lastname: Swayne
authors.forename: A I
authors.initials: AI
authors.lastname: Klimov
authors.forename: L G
authors.initials: LG
authors.lastname: Rudenko