Study of adjuvant effect of fosprenil on immunogenicity of vaccines against parvovirus enteritis and rabies in experiment

To prevent most common viral diseases of small pets, vaccines are most often used that stimulate animal immune system and provide specific protection. Data on the adjuvant properties of well-known and widely used immunomodulator of natural origin, fosprenil, used in veterinary practice as an immunomodulator with antiviral activity for the correction of the immune response in various viral infections, during experimental immunization of BALB/mouse vaccines against dog parvovirus enteritis and rabies are presented in the article. It was shown that fosprenil use in animals at immunostimulating dose (5 pg/mouse) significantly enhances the effect of immunization with both vaccines. So, fosprenil significantly increases the titer of post-vaccination antibodies to standard liquid inactivated vaccine against parvovirus enteritis in dogs. In experiments with the rabies vaccine, it was found that the administration of fosprenil in animals along with vaccine not only contributes to significant increase in the titer of specific antibodies, but also to significant increase in coefficient of protective activity of rabies vaccine. Thus, fosprenil exerts an adjuvant effect on post-vaccination immunity caused by vaccination of mice with rabies and parvovirus enteritis vaccines.

Analysis of experimental mouse PRNP genetic polymorphisms and their susceptibility to prion diseases

Research studies showed that the polymorphisms in prion protein gene (PRNP) were associated with susceptibility to prion diseases in several animals, including humans and mouse. Several mouse strains carried natural PRNP mutations which had been identified and these could provide as animal models for human prion diseases. In this study, the genetic polymorphisms of PRNP in six common mouse strains were investigated. The experimental mice included KM mouse, ICR mouse, DBA mouse, C3H/He mouse, C57BL mouse and BALB mouse. The results showed only one new polymorphism was identified compared with the reference sequence. The identified new mutation site was C564T and it was homozygous, but this locus did not result in amino acid change. Sequence analyses suggested that these six mouse strains were susceptible to prion diseases and are suitable as susceptibility models of prion diseases.

A new differentiation antigen (FT-1) shared with fetal thymocytes and leukemic cells in the mouse.

A mouse monoclonal antibody (IgM) was obtained by cell hybridization between X63-Ag8.653 myeloma cells and spleen cells from a BALB mouse that was immunized with GRSL leukemia cells of the GR strain. This antibody identified a unique fetal antigen, which is expressed exclusively on embryonic thymocytes of all strains tested. Therefore, the antigen defined was named fetal thymus antigen-1, FT-1. The proportion of FT-1+ fetal thymocytes detected by immunofluorescence assay sharply decreases as gestation time increases, and finally they disappear from the thymus. On the other hand, Thy-1+ cells increase in inverse proportion. The immunofluorescence studies and absorption tests showed that FT-1 antigen is not detectable on brain, liver, kidney, or lymphoid tissue cells of adult mice. However, it is expressed on some leukemia cells of various mouse strains, which demonstrated that this is the first example of an oncofetal antigen of a mouse leukemia. The molecular weight of FT-1 antigen on leukemia cells was estimated to be 130,000 by means of biosynthetic labeling with [3H]galactose and [35S]methionine. The two-dimensional gel electrophoresis pattern of FT-1 antigen shows a family of glycoproteins with extensive charge heterogeneity. It was also shown that the FT-1 antigen molecule carries the receptor for DBA lectin.