Characterization of an Experimental Vaccine for Bovine Respiratory Syncytial Virus

Abstract

Bovine respiratory syncytial virus (BRSV) and human respiratory syncytial virus (HRSV) are major causes of respiratory disease in calves and children, respectively, and are priorities for vaccine development. We previously demonstrated that an experimental vaccine, BRSV-immunostimulating complex (ISCOM), is effective in calves with maternal antibodies. The present study focuses on the antigenic characterization of this vaccine for the design of new-generation subunit vaccines. The results of our study confirmed the presence of membrane glycoprotein (G), fusion glycoprotein (F), and nucleoprotein (N) proteins in the ISCOMs, and this knowledge was extended by the identification of matrix (M), M2-1, phosphoprotein (P), small hydrophobic protein (SH) and of cellular membrane proteins, such as the integrins ␣ V ␤ 1 , ␣ V ␤ 3 , and ␣ 3 ␤ 1 . The quantity of the major protein F was 4-to 5-fold greater than that of N (ϳ77 g versus ϳ17 g/calf dose), whereas G, M, M2-1, P, and SH were likely present in smaller amounts. The polymerase (L), M2-2, nonstructural 1 (NS1), and NS2 proteins were not detected, suggesting that they are not essential for protection. Sera from the BRSV-ISCOM-immunized calves contained high titers of IgG antibody specific for F, G, N, and SH. Antibody responses against M and P were not detected; however, this does not exclude their role in protective T-cell responses. The absence of immunopathological effects of the cellular proteins, such as integrins, needs to be further confirmed, and their possible contribution to adjuvant functions requires elucidation. This work suggests that a combination of several surface and internal proteins should be included in subunit RSV vaccines and identifies absent proteins as potential candidates for differentiating infected from vaccinated animals.

Use of Genomic Tools to Improve Cattle Health in the Context of Infectious Diseases

“…Such a systematic approach culminated in the development of a live virus BRSV vaccine that showed pronounced protection of calves from subsequent infection. Detailed analysis of immunogenic and functional characteristics of the virus was followed by genetic engineering to develop a recombinant virus with a deletion of one of its pathogenicity genes ( Blodorn et al, 2014 ; Hagglund et al, 2014 ). An even more intricate approach was undertaken in the development of a novel BHV-1 vaccine where, based on past knowledge, the authors deleted three genes known to be responsible for anterograde neuronal transfer of the virus as well as avoidance of the host immune response.…”

Transplacental Antibody Transfer of Respiratory Syncytial Virus Specific IgG in Non-Human Primate Mother-Infant Pairs

“…Mice [82,83], cotton rats [84,85], cows [86], sheep [87], in vitro cell and tissue systems and even mathematical modelling [88] have provided insight into maternal immunization [89][90][91]. We know from clinical studies that Nab levels correlate with protection from RSV disease [92,93].…”

Proteome analysis of bronchoalveolar lavage from calves infected with bovine respiratory syncytial virus—Insights in pathogenesis and perspectives for new treatments

“…Larsen, DTU, Denmark), 6 days previously, and were either a) non-vaccinated and showed clinical signs of disease and shed high quantities of virus (n = 5, called susceptible_I), or b) BRSV-ISCOM-vaccinated and showed little or no clinical signs of disease and shed little or no virus (n = 5, called vaccinated) ( Table 1 ) [ 9 ]. As described in detail previously [ 11 ], this vaccine consisted of pleomorphic nanoparticles that contained purified, solubilized proteins from BRSV-infected cell culture, as well as lipids and Quillaja saponin.…”

“…Dotblots and Western blots were carried out as described previously [ 11 ], using polyclonal rabbit antibodies against myeloperoxidase or histone H3 citrulline 2+8+17 peptide (ab14323 and ab5103, Abcam,) and polyclonal HRP-conjugated sheep antibodies against rabbit IgG (Star 54, Bio-Rad). Controls using BAL antigen and the secondary antibodies alone were included.…”