Evaluation of the Replication, Pathogenicity, and Immunogenicity of Avian Paramyxovirus (APMV) Serotypes 2, 3, 4, 5, 7, and 9 in Rhesus Macaques

Khattar, Sunil K.; Nayak, Baibaswata; Kim, Shin-Hee; Xiao, Sa; Samal, Sweety; Paldurai, Anandan; Buchholz, Ursula J.; Collins, Peter L.; Samal, Siba K.

(ii) a recombinant derivative of wt APMV-2, called rAPMV-2 (type 1 Africa), in which the natural cleavage site was replaced by the cleavage site RRRRRQF that is present in a APMV type 1 strain isolated in Africa [16] ; (iii) biologically-derived wt APMV-3 strain parakeet/Netherland/449/75 [9] ; (iv) recombinant wt APMV-4 strain duck/Hong Kong/D3/75 [10] ; (v) a derivative of rAPMV-4, called rAPMV-4/Fc-BC, in which its natural cleavage site was replaced by the cleavage site RRQKRQF that is present in mesogenic NDV strain Baudette C [19] ; (vi) biologically-derived wt APMV-5 strain budgerigar/Kunitachi/74 [11] ; (vii) biologically-derived wt APMV-7 strain dove/Tennessee/4/75 [13] ; (viii) a recombinant derivative of wt APMV-7, called rAPMV-7/Fcs-5B in which its natural cleavage site was replaced by the cleavage site RRKKRQFI present in a velogenic NDV strain Nigeria/95, and which includes an amino acid substitution in the +2 position relative to the cleavage site [18] ; and (ix) biologically-derived wt APMV-9 strain duck/New York/22/78 [15] . All the APMV serotypes except serotype 5 were grown in the allantoic cavity of 9day-old specific-pathogen-free (SPF) embryonated chicken eggs. APMV-5 was grown in Vero cells. The allantoic fluids from infected eggs were collected 72 h post-inoculation and virus titers were determined by hemagglutination (HA) assay. Further, the titers of APMVs were determined by plaque assay on DF-1 cells for APMV-2, -3, -4 and -9 and on Vero cells for APMV-5 and -7. The samples were inoculated in triplicate onto 24-well plates of DF-1 or Vero cells at 80% confluency and virus titer was determined by either plaque assay or immunostaining with N specific antibodies.