Assessment of DNA vaccine potential for juvenile Japanese flounderParalichthys olivaceus, through the introduction of reporter genes byparticle bombardment and histopathology

摘要

Genetic immunisation potential, following DNA bombardment for juvenile Japanese flounder, Paralichthys olivaceus was examined. GFP plasmids bombarded at two pressures, 150 and 300psi were sampled at 1, 7, 14 and 28 days, greater immunofluorescence was observed at the higher bombardment pressure. Histopathology, at 3 h post bombardment showed considerable damage to fish epithelial and dermal tissues when bombarded at pressures greater than 200 psi, with many DNA-coated gold particles present. At 150psi there was little pathology and no DNA-coated particles. Histopathology, up to 28 days again showed little pathology at 150 psi with few DNA-coated particles, whereas at 300 psi there was significant pathology observed with many DNA-coaled particles seen in conjunction with the cytoplasm of inflammatory cells. By day 28 epithelial coverage was observed with tissue damage restricted to the dermal layer. Chloramphenicol acetyltransferase (CAT) assay showed long term and stable expression of the CAT protein from day 1 to day 60. The transcription activity of two promoters; pCMV-CAT and pSV2-CAT showed greater activity in the former. It was concluded that DNA vaccination potential for juvenile flounder is a viable option.