Efficacy of DNA vaccine encoding koi herpesvirus glycoprotein GP-25in common carp juvenile by immersion

Abstract

<p class="Default">Koi herpesvirus (KHV) is a herpesvirus that particularly infects and causes mass mortality to koi and common carp. Therefore, the protection of common carp from KHV infection is urgently needed. In this study, we developed an application of DNA vaccine encoding KHV glycoprotein-25 by immersion method to increase survival of common carp against KHV infection. A total of 400 common carp juveniles at 30-day-old were immersed in 1-L water containing 1.3×10<sup>8</sup>CFU/mL of the killed <em>Escherichia coli</em> cells carrying DNA vaccine. Three frequencies and three duration of fish immersion were tested, namely: 1×30 minutes, 1×60 minutes, 1× 90 minutes, 2×90 minutes and 3×90 minutes by interval of 24 hours. Reversetranscription polymerase chain reaction analysis showed that DNA vaccine was successfully expressed in the vaccinated fish. Fish at twenty eight days post vaccination were challenged by injecting 10<sup>-4</sup> mL of KHV per fish. The result showed that vaccination by 1×30 minutes immersion allowed 61% of fish survived, and this was significantly higher (p<0.05) compared to control (without vaccination), but it was similar among vaccination treatments (p>0.05). The relative percent survival of vaccinated fish were also similar among treatments (p>0.05). DNA vaccination has increased fish survival about two fold higher compared to unvaccinated fish control (26.67%). Thus, DNA vaccination was effectively delivered by immersion for 1×30 minutes, and this technique can be useful to level up the resistance of common carp juveniles against KHV infection.</p> <p class="Default">Keywords: DNA vaccine, KHV, glycoprotein, immersion, common carp</p>

Efficacy of koi herpesvirus DNA vaccine administration by immersion method onCyprinus carpiofield scale culture

“…These results completed the previous studies, in which the expression of GP25 DNA vaccine through immersion method was observed up to 28 dpv (Nuswantoro et al . ). Specific antibody response formed is important parameter of vaccination effect.…”

“…The immersion was performed for 30 min (Nuswantoro et al . ). The experimental fish were re‐stocked and reared in aquariums according to vaccination densities for 30 days (water temperature at 28 ± 1°C).…”

“…The challenged test was performed by intramuscular (IM) route injection of 0.1 mL KHV filtrate with a concentration of 10 −3 (Nuswantoro et al . ). As a negative control (K − ), fish without vaccination were injected with PBS and as the positive control (K + ), fish without vaccination were injected with 0.1 mL of KHV filtrate.…”

“…Research and development of DNA vaccine against KHV infection showed promising results. Application of DNA vaccine is capable in inducing specific antibody production on common carp against KHV and decreasing mortality rate during the challenge test (Nuryati, Alimuddin, Sukenda, Soejoedono, Santika, Pasaribu & Sumantadinata ; Nuswantoro, Alimuddin, Yuhana, Santika, Nuryati, Zainun & Mawardi ; Nuryati, Yuliyanti & Alimuddin ; Zhou, Wang, Li, Lu & Zhang ; Zhou, Xue, Wang, Zhu, Li, Wenliang & Zhang ). Construction of KHV DNA vaccine encoding glycoprotein‐25 (GP25) has been developed in our laboratory through some tests.…”

“…), immersion (Nuswantoro et al . ) and oral (Nuryati & Alimuddin ). Injection method has generally been done and has higher effectiveness, but immersion vaccination is more applicable method and can be used on fish fingerlings in the mass scale.…”