Enhancement of feline immunodeficiency virus infection after immunization with envelope glycoprotein subunit vaccines

• Published in: Journal of Virology Vol. 69; no. 6; pp. 3704 - 3711
• Main Authors: Siebelink, K.H.J. (Erasmus University Rotterdam, Rotterdam, The Netherlands.), Tijhaar, E, Huisman, R.C, Huisman, W, Ronde, A. de, Darby, I.H, Francis, M.J, Rimmelzwaan, G.F, Osterhaus, A.D.M.E
• Format: Journal Article
• Language: English
• Published: United States American Society for Microbiology 01.06.1995
• Subjects: AIDS/HIV; Animals; Antibodies, Viral - biosynthesis; Antibodies, Viral - blood; ANTIGENE; ANTIGENOS; Cats; Cell Line; CHAT; CULTIVO DE CELULAS; CULTURE DE CELLULE; Feline Acquired Immunodeficiency Syndrome - immunology; feline immunodeficiency virus; GATO; GLICOPROTEINAS; GLYCOPROTEINE; Glycoproteins - immunology; IMMUNISATION; IMMUNITE PASSIVE; Immunization; Immunodeficiency Virus, Feline - immunology; INFECCION; INFECTION; INMUNIDAD PASIVA; INMUNIZACION; Kinetics; LENTIVIRINAE; LINFOCITOS; LYMPHOCYTE; Monocytes - virology; PODER PATOGENO; POUVOIR PATHOGENE; PROTEINAS; PROTEINE; REACCION ANTIGENO-ANTICUERPO; REACTION ANTIGENE ANTICORPS; REIN; REPONSE IMMUNITAIRE; RESPUESTA INMUNOLOGICA; RINONES; VACCIN SYNTHETIQUE; VACCINATION; vaccinia virus; VACUNA SINTETICA; VACUNACION; Viral Envelope Proteins - immunology; Viral Vaccines - immunology; VIRUS DE LOS ANIMALES; VIRUS DES ANIMAUX
• ISSN: 0022-538X; 1098-5514
• DOI: 10.1128/jvi.69.6.3704-3711.1995

Cats were immunized three times with different recombinant feline immunodeficiency virus (FIV) candidate vaccines. Recombinant vaccinia virus (rVV)-expressed envelope glycoprotein with (vGR657) or without (vGR657x15) the cleavage site and an FIV envelope bacterial fusion protein (beta-Galactosidase-Env) were incorporated into immune stimulating complexes or adjuvanted with Quil A. Although all immunized cats developed antibodies against the envelope protein, only the cats vaccinated with the rVV-expressed envelope glycoproteins developed antibodies which neutralized FIV infection of Crandell feline kidney cells. These antibodies failed to neutralize infection of thymocytes with a molecularly cloned homologous FIV. After the third immunization the cats were challenged with homologous FIV. Two weeks after challenge the cell-associated viral load proved to be significantly higher in the cats immunized with vGRC57 and vGR657x15 than in the other cats. The cats immunized with vGR657 and vGR657x15 also developed antibodies against the Gag proteins more rapidly than the cats immunized with beta-Galactosidase-Env or the control cats. This suggested that immunization with rVV-expressed glycoprotein of FIV results in enhanced infectivity of FIV. It was shown that the observed enhancement could be transferred to naive cats with plasma collected at the day of challenge