0000000000190081
AUTHOR
Jacqueline Gelfi
Myxoma virus Leukemia-associated protein is responsible for major histocompatibility complex class I and Fas-CD95 down-regulation and defines scrapins, a new group of surface cellular receptor abductor proteins
ABSTRACTDown-modulation of major histocompatibility class I (MHC-I) molecules is a viral strategy for survival in the host.Myxoma virus, a member of thePoxviridaefamily responsible for rabbit myxomatosis, can down-modulate the expression of MHC-I molecules, but the viral factor(s) has not been described. We cloned and characterized a gene coding for an endoplasmic reticulum (ER)-resident protein containing an atypical zinc finger and two transmembrane domains, which we called myxoma virus leukemia-associated protein (MV-LAP). MV-LAP down-regulated surface MHC-I and Fas-CD95 molecules upon transfection; the mechanism probably involves an exacerbation of endocytosis and was lost when the ER r…
Protection of rabbits against rabbit viral haemorrhagic disease with a vaccinia-RHDV recombinant virus
In order to protect domestic and wild rabbits against RVHD, we constructed a recombinant vaccinia-RHDV virus, using the Copenhagen strain of the vaccinia virus. This recombinant virus expressed the RHDV capsid protein (VP60). Analysis of the expressed product showed that the recombinant protein, which is 60 kDa in size, was antigenic as revealed by its reactions in immunoprecipitation and indirect immunofluorescence with the antibodies raised against RHDV. The recombinant virus induced high level of RHDV specific antibodies in rabbits following immunization. Inoculations by both the intradermal and oral routes allow protection of animals against a challenge with virulent RHDV.
Determinants essential for the transmissible gastroenteritis virus-receptor interaction reside within a domain of aminopeptidase-N that is distinct from the enzymatic site
The swine-specific coronavirus transmissible gastroenteritis virus (TGEV) uses pig aminopeptidase-N (pAPN) as a cellular receptor. We showed that the human aminopeptidase-N (hAPN) cannot substitute for pAPN in this respect, although the two enzymes have 80% amino acid sequence identity. In order to map the TGEV binding site on pAPN, we constructed a series of APN cDNA chimeras between pAPN and hAPN and analyzed them for their capacity to confer infectivity. The region between residues 717 and 813 was found to be essential for infectivity. This region also contains the epitopes for three TGEV-blocking monoclonal antibodies directed against pAPN. These data support the view that the catalytic…
Protection against myxomatosis and rabbit viral hemorrhagic disease with recombinant myxoma viruses expressing rabbit hemorrhagic disease virus capsid protein
Two myxoma virus-rabbit hemorrhagic disease virus (RHDV) recombinant viruses were constructed with the SG33 strain of myxoma virus to protect rabbits against myxomatosis and rabbit viral hemorrhagic disease. These recombinant viruses expressed the RHDV capsid protein (VP60). The recombinant protein, which is 60 kDa in size, was antigenic, as revealed by its reaction in immunoprecipitation with antibodies raised against RHDV. Both recombinant viruses induced high levels of RHDV- and myxoma virus-specific antibodies in rabbits after immunization. Inoculations by the intradermal route protected animals against virulent RHDV and myxoma virus challenges.