Novel biotechnological platform based on baculovirus occlusion bodies carrying Babesia bovis small antigenic peptides for the design of a diagnostic enzyme-linked immunosorbent assay (ELISA)

PALLARÉS HORACIO MARTÍN; FARBER MARISA; LOPEZ MARÍA GABRIELA; CARMONA SANTIAGO; WILCOWSKI SILVINA; ALFONSO VICTORIA; TABOGA OSCAR; PALLARÉS HORACIO MARTÍN; FARBER MARISA; LOPEZ MARÍA GABRIELA; CARMONA SANTIAGO; WILCOWSKI SILVINA; ALFONSO VICTORIA; TABOGA OSCAR

APPLIED MICROBIOLOGY AND BIOTECHNOLOGY

SPRINGER

Lugar: Berlin; Año: 2018 vol. 102 p. 885 - 896

0175-7598

Baculoviruses are large DNA virus of insects principally employed in recombinant protein expression. Its ability to form occlusion bodies (OBs), which are composed mainly of polyhedrin protein (polh), make them biotechnologically attractive, as these crystals (polyhedra) can incorporate foreign peptides and can be easily isolated. On the other hand, peptide microarrays allow rapid and inexpensive high-throughput serological screening of new candidates to be incorporated to OBs. To integrate these 2 biotechnological approaches, we worked on Babesia bovis, one of the causative agents of bovine babesiosis. Current molecular diagnosis of infection with B. bovis includes enzyme-linked immunosorbent assay (ELISA) techniques, which use merozoite lysate obtained from infected bovine erythrocytes. However, it is important to produce recombinant antigens that replace the use of crude antigens. Here we describe a new biotechnological platform for the design of indirect ELISAs based on 5 15-mer antigenic peptides of B. bovis (ApBb) selected from a peptide microarray and expressed as a fusion to polyhedrin. An Sf9POLHE44G packaging cell line infected with recombinant baculoviruses carrying POLH-ApBb fusions yielded higher levels of chimeric polyhedra, highlighting the advantage of a trans-contribution of a mutant copy of polh. Finally, the use of dissolved recombinant polyhedra as antigens was successful in an ELISA assay, as B. bovis-positive sera recognized the fusion POLH-ApBb. Thus, the use of this platform resulted in a promising alternative for molecular diagnosis of relevant infectious diseases.