In vitro model for producing antigens of equine infectious anemia and bovine immunodeficiency-Zike viruses

L'absence d'un modèle cellulaire adéquat restreint la production d'anti gènes des virus de l'anémie infectieuse des équidés (VAIE) et de l'immuno- déficience bovine (VIB). Dans une première phase, le développement du modèle implique : 1) des cellules d'une lignée continue susceptibles au virus ; 2) une infection permanente ; 3) une production continue d'antigènes en milieu sans sérum. Dans une deuxième phase, les antigènes sont produits en grande quantité et sans interruption dans un bioréacteur. La première phase a été atteinte par l'infection permanente de deux lignées canines par le VAIE et le VIB, mais n'a pas été complétée avec le VIB à cause de l'absence d'épreuves sérologiques détectant les antigènes. La deuxième phase est encore à l'étude pour les deux virus.In vitro antigen production of equine infectious anemia (EIAV) and bovine immunodeficiency-like (BIV) viruses is hampered by the absence of adequate cellular models. The first step required in the development of such models depends on criteria such as : 1) viral permissiveness of cells in a continuous line ; 2) persistent infection ; 3) continuous production of antigen in a serum-free medium. The second step involves the large-scale production of antigen in a bioreator. The first step was achieved by initiating persistent infection of two canine cell lines by EIAV and BIV respectively. However, the method of BIV antigen production has not been completed due to the lack of adequate serological tests for detection of antigens. The second step involving both viruses is under study

Structural characterization and serological specificities of lipopolysaccharides from Salmonella enterica serovar Gallinarum biovar Pullorum standard, intermediate and variant antigenic type strains: Vet.Microbiol.

The structure and serological specificities of the lipopolysaccharides (LPSs) from Salmonella enterica serovar Gallinarum biovar Pullorum were studied to provide an improved basis for the distinction between antigenic types and the development of improved diagnostic tests. The structure of the LPS O-polysaccharide (O-PS) from S. Pullorum standard, intermediate and variant antigenic type strains was determined by mass spectrometry, nuclear magnetic resonance spectroscopy and chemical analysis. The LPS of the three strains shared a common structural repeating oligosaccharide unit containing d-mannose, l-rhamnose, d-galactose and d-tyvelose (1:1:1:1). The O-PS of the variant type LPS contained an additional d-glucose residue linked to the O-4 position of the d-galactose residue. The O-PS of the intermediate type LPS was partially the same as that of the variant LPS, however, the molar ratio of the d-glucose component was lower with respect to the other glycose components. Serological specificities of the three antigenic type LPSs were examined with anti-S. Pullorum LPS monoclonal antibodies (Mabs). On immunoblots, Mabs to the standard type O-PS reacted with high molecular mass (HMM) and low molecular mass (LMM) LPS from the standard strain, and with LMM but not HMM LPS from the variant strain. Monoclonal antibodies to the variant type O-PS reacted with HMM but not LMM LPS from the variant strain, and did not react with HMM or LMM LPS from the standard strain. On ELISA, the standard, intermediate and variant antigenic type strains were differentiated by the relative reactivity with the anti-LPS O-PS Mabs. Several of the anti-LPS O-PS Mabs were specific for S. Pullorum and other serogroup D1 Salmonella, and are potentially useful for the development of improved diagnostic tests for these organismsNRC publication: Ye