ABSTRACT
Leptospirosis can cause severe disease and probable death in humans. Antigenic epitopes from pathogenic strains of
the bacteria have shown potential for serving as vaccine candidates and play a key role in the sensitivity and
specificity of immunodiagnostic tests. This in-vitro analysis was undertaken to develop a prototype recombinant
DNA vaccine using in-silico epitope prediction method. Epitope prediction software programs predicted the most
antigenic linear B-cell epitopes of OmpL1, LipL32, LipL41, Loa22, and LigA. Thirteen epitopes were predicted,
connected by the Gly-Ser linker, and synthesized. The purity of the concentrated recombinant multi-epitope protein
was assessed by restriction enzyme digestion and gel electrophoresis. In-vitro expression on mammalian Chinese
Hamster Ovary cell line indicated strong cytoplasmic fluorescence produced based on an indirect
immunofluorescence antibody test. The green color of the cytoplasm indicates successful transcribed and translated
DNA as against the blue-stained nucleus observed in the un-transfected control group based on the indirect
immunofluorescence antibody test. The findings of the current study showed high antibody binding potentials of the
vaccine constructs, which could be used for diagnostic applications or as polyvalent vaccine candidates.