ABSTRACT
Following inactivated virus vaccination trials, the surface glycoprotein gp120 of the feline immunodeficiency virus (FIV) was considered as one of the determinants for protection. However, several vaccination trials using recombinant Env protein or some peptides failed to induce protection. To understand the role of the gp120 protein in vivo, we vaccinated cats with naked DNA coding for FIV structural proteins gp120 and p10. We analyzed the ability of these vaccinations to induce immune protection and to influence the onset of infection. Injection in cat muscles of expression vectors coding for the FIV gp120 protein induced a humoral response. Cats immunized twice with the gp120 gene showed different patterns after challenge. Two cats were, like the control cats, infected from the second week after infection onwards. The two others maintained a low proviral load with no modification of their antibody pattern. The immune response induced by gp120 DNA injection could control the level of viral replication. This protective-like immune response was not correlated to the humoral response. All the cats immunized with the gp120 gene followed by the p10 gene were infected, like the control cats, from the second week but they developed a complete humoral response against viral proteins after challenge. Furthermore, they showed a sudden but transient drop of the proviral load at 4 weeks after infection. Under these conditions, one injection of the p10 gene after one injection of the gp120 gene was not sufficient to stimulate protection. On the contrary, after a period, it seems to facilitate virus replication.
Subject(s)
Genes, Viral , Immunodeficiency Virus, Feline/genetics , Immunodeficiency Virus, Feline/immunology , Vaccines, DNA/pharmacology , Viral Structural Proteins/genetics , Viral Vaccines/pharmacology , Animals , Antibodies, Viral/biosynthesis , Cats , Feline Acquired Immunodeficiency Syndrome/immunology , Feline Acquired Immunodeficiency Syndrome/prevention & control , Gene Products, env/genetics , Gene Products, env/immunology , Gene Products, gag/genetics , Gene Products, gag/immunology , Genetic Vectors , Immunodeficiency Virus, Feline/physiology , Proviruses/genetics , Vaccines, DNA/genetics , Viral Vaccines/genetics , Virus ReplicationABSTRACT
Serum protein, immunoglobulins, complement, lysozyme, serum bactericidal activity and blast transformation of peripheral blood lymphocytes were tested in beef cattle in different herds and age groups. These parameters were evaluated in their time-kinetics, in comparison with age-matched groups of dairy cattle. Like dairy calves, beef calves up to 4 months of age were shown to have low levels of serum bactericidal activity and haemolytic complement; besides, a worse profile was detected in serum protein and gamma 2 globulin levels. Al(OH)3 and oil-adjuvanted vaccines had a favourable influence on immunoglobulin and lysozyme synthesis. An acute stressing event like transportation was shown to decrease mitogen-driven lymphocyte stimulation for at least 10 days after arrival.
Subject(s)
Cattle/immunology , Animals , Blood Bactericidal Activity , Blood Proteins/analysis , Complement System Proteins/analysis , Female , Immunity, Innate , Immunoglobulins/analysis , Lymphocyte Activation , Muramidase/blood , Reference ValuesABSTRACT
Canine retinal S antigen has been purified to study the retinal progressive atrophy of the dog. The purified antigen will be used to detect, by the ELISA technique, specific autoantibody in dogs with ocular diseases.
