Canine parvovirus empty capsids produced by expression in a baculovirus vector: use in analysis of viral properties and immunization of dogs

Abstract

The VP-2 genes of canine parvovirus (CPV) and a recombinant consisting of CPV and feline panleukopenia virus (FPV) sequences were cloned into baculovirus expression vectors, fused to the baculovirus polyhedrin promoter. Recombinant baculoviruses were prepared and the properties of the parvovirus proteins expressed in insect cells examined. The proteins produced were the same size as the authentic CPV VP-2 protein, and were produced late after infection; the quantity of proteins recovered from the insect cell cultures was similar to those produced in CPV infections. Parvovirus particles formed had the haemagglutination (HA), sedimentation and buoyant density properties of authentic CPV capsids. Both the CPV capsids and the CPV-FPV recombinant capsids from the baculovirus system expressed the same epitopes as those seen in the viable parvoviruses when tested with a panel of antiparvovirus monoclonal antibodies. Lysates of recombinant baculovirus-infected cells were inoculated into dogs, giving rise to serum neutralizing and HAinhibiting antibodies, and the immunized dogs were protected from clinical disease upon challenge with a virulent isolate of the most recent antigenic type of CPV.

Minute Virus of Mice, a Parvovirus, in Complex with the Fab Fragment of a Neutralizing Monoclonal Antibody

“…VP3, a proteolytic cleavage product of VP2, has been observed only in DNAcontaining particles (1,13,51,67). Empty, recombinant viruslike particles (VLPs), self-assembled from MVMp VP2, are morphologically and immunologically similar to native, empty MVMp particles (11,23,35,56), as demonstrated previously for other parvoviral VLPs (29,38,39,57).…”

Serodiagnosis of Mice Minute Virus and Mouse Parvovirus Infections in Mice by Enzyme-Linked Immunosorbent Assay with Baculovirus-Expressed Recombinant VP2 Proteins

“…These vectors were used to express the recombinant capsid proteins MMV rVP2 and MPV rVP2 in insect cells. It is known that many parvovirus recombinant VP2 proteins, including MMV rVP2, assemble into virus-like particles (VLPs) when expressed in baculovirus expression systems (6,8,16,24,27). To determine if baculovirus-expressed MMV rVP2 or MPV rVP2 proteins self-assembled into VLPs, we subjected clarified supernatants of insect cells infected with the MMV-rVP2 Bac vector or the MPV-rVP2 Bac vector to CsCl gradient ultracentrifugation.…”

Assembled baculovirus-expressed human papillomavirus type 11 L1 capsid protein virus-like particles are recognized by neutralizing monoclonal antibodies and induce high titres of neutralizing antibodies

“…One such strategy to generate the correct surface topography of viruses synthetically is to produce artificial virus-like particles (VLPs) by overexpression of the viral coat proteins in various expression systems (Urakawa et al, 1989;Saliki et al, 1992;Brown et al, 1991 ;Kajigaya et aI., 1991;Montross et al, 1991;French et al, 1990;Spehner et al, 1991 ;Zhou et al, 1991Zhou et al, , 1992Haffar et al, 1990;Rumenapf et al, 1991;Jones et al, 1990;Martinez et al, 1992;Kirnbauer et al, 1993). The production of VLPs for some viruses such as polyomavirus and parvovirus has even been accomplished successfully by expression of the major coat protein alone (Montross et al, 1991;Brown et al, 1991;Martinez et al, 1992).…”