Effect of VP28 DNA vaccine on white spot syndrome virus in Litopenaeus vannamei

Abstract

White spot syndrome virus (WSSV) occurs worldwide and causes high mortality and considerable economic damage to the shrimp farming industry. Considering the global environmental, the economic and sociological importance of shrimp farming, and the constraints of high intensity cultivation, development of novel control measures against the outbreak of WSSV become inevitable. In this study, we have explored the protective efficacy of DNA vaccination and tissue distribution of the recombinant plasmid in immunized Litopenaeus vannamei. The VP28 gene was cloned in the eukaryotic expression vector pVAX1, and the construct vector was named as lpv28. The protective effect of lpv28 against WSSV was evaluated in L. vannamei by injecting lpv28 construct and later challenging with WSSV. Expression of these proteins from the recombinant plasmids was confirmed in vitro by RT-PCR and Western blot analysis. The result of vaccination trials showed that a survival rate in shrimp vaccinated with lpv28 was 52.5% at most compared to control groups (100% mortality). The immunological parameters analyzed in the vaccinated and control groups showed that the vaccinated groups owned a high level of lysozyme, alkaline phosphatase, and total superoxide dismutase when compared to the control group. Furthermore, protein expression analysis indicated that VP28 can be detected in gill, muscle and head soft tissue of the shrimps in the immunized group after 14th day injection. Thus, the result indicated that DNA vaccination strategy has a potential utility against WSSV.

Immune responses and immunoprotection in crustaceans with special reference to shrimp

“…Similar attempts to vaccinate shrimps against WSSV using DNA vaccines have been carried out by Kumar et al (2008), Kono et al (2009), and Li et al (2010). Among these studies, Kumar et al (2008) showed a convincing survival of 66.6 % in shrimp injected with a plasmid expressing VP28 followed by WSSV challenge on 21 days postimmunization.…”

Challenges and prospects of Viral Envelope protein VP28‐based control strategies to combat white spot syndrome virus in penaeid shrimps: a review

“…However, the intensity of DNA vaccine‐lpv28 expression declined and thus the protection of L. vannamei against WSSV infection, as the RPS value decreased significanlty after 14th day compared to that of 7th day (Li et al . 2010). VP28 transcripts obtained from expression vector was detected in haemocyte, hepatopancreas, muscle, stomach, gill, intestine, eyestalk, heart, epidermis, lymph organ, ventral nerve cord, testis and ovary at 1, 3 and 7 days post vaccination, while the survival rate of the vaccinated was 60% above the control group.…”

Creation of recombinant Chlamydomonas reinhardtii strains expressing codon optimized vp28 gene from white spot symdrome virus

“…WSSV chứa 5 loại protein cấu trúc chính là VP28, VP26, VP24, VP19 và VP15; trong đó VP28 và VP26 là hai protein biểu hiện trên vỏ virus. Do tính kháng nguyên cao và khả năng kích thích hệ thống miễn dịch của tôm, VP26 và VP28 thường được sử dụng làm marker chẩn đoán virus hoặc kháng nguyên đích cho vaccine phòng WSSV (van Hulten et al, 2001;Witteveldt et al, 2004;Rout et al, 2007;Li X et al, 2010;Syed et al, 2011). rVP28 đã được nghiên cứu biểu hiện ở nhiều hệ thống khác nhau như E. coli, nấm men, baculovirus (Rajeev et al, 2005;Syedet al, 2009;Hou et al, 2011).…”