Expression of the potyvirus coat protein mediated by recombinant vaccinia virus and assembly of potyvirus-like particles in mammalian cells

CSIRO, Australian Animal Health Laboratory, Geelong, Victoria, Australia.
Archives of Virology (Impact Factor: 2.39). 02/1998; 143(7):1433-9. DOI: 10.1007/s007050050387
Source: PubMed


The coat protein of the potyvirus, Johnsongrass mosaic virus (JGMV), was expressed using a recombinant vaccinia virus (VV) system. Ultra-thin section electron microscopy demonstrated that the coat protein assembled into potyvirus-like particles (PVLPs) in recombinant VV infected cells. Infection of cells with two additional VV recombinants expressing coat protein plus N-terminal and N- and C-terminal extensions also resulted in the formation of PVLPs. These results suggest that the ability of VV to express the potyvirus coat protein at sufficient levels to allow PVLP formation in vitro, could make VV a suitable vector for the delivery of PVLPs displaying vaccine antigens in vivo without the need for particle purification and/or inclusion of adjuvant. Use of such a vaccine strategy would also benefit from the proven advantages of poxviruses as vaccines such as stability in a freeze dried form, resistance to environmental factors and the potential for oral administration.

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    • "A " ring " -like aggregate was also observed and it was suggested to be an intermediate in the reassembly of potyviruses . Potyviral CP has been expressed in Escherichia coli, yeast, insect, and mammalian systems (Edwards et al., 1994; Hammond et al., 1998; Jagadish et al., 1991; Joseph and Savithri, 1999) and in all the systems the formation of heterogeneous length filamentous virus-like particles (VLPs) were reported. One interesting feature of the potyviruses and their VLPs in general is that the amino-and carboxy-terminal regions of the CPs are surface exposed and they can be removed by limited trypsin treatment without affecting the assembly status (Jagdish et al., 1993). "
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