Immunogenicity of a recombinant infectious hematopoietic necrosis virus glycoprotein produced in insect cells

Diseases of Aquatic Organisms

Bill Shewmaker¹  Kenneth D. Cain¹  Scott E. LaPatra¹  Sandra S. Ristow¹  Jerry Jones¹  Katherine M. Byrne¹ 

关键词: IHNV;    Baculovirus;    Recombinant glycoprotein;    Immunization;    Rainbow trout;   

DOI  :  10.3354/dao036067

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: A recombinant infectious hematopoietic necrosis virus (IHNV) glycoprotein (G protein), produced in Spodoptera frugiperda (Sf9) cells following infection with a baculovirus vector containing the full-length (1.6 kb) glycoproteingene, provided very limited protection in rainbow trout Oncorhynchus mykiss challenged with IHNV. Fish were injected intraperitoneally (i.p.) with Sf9 cells grown at 20°C (RecG_low) or 27°C (RecG_high) expressing theglycoprotein gene. Various antigen (Ag) preparations were administered to adult rainbow trout or rainbow trout fry. Sera collected from adult fish were evaluated for IHNV neutralization activity by a complement-dependent neutralization assay. Anti-IHNVneutralizing activity was observed in sera, but the percent of fish responding was significantly lower (p < 0.05) in comparison to fish immunized with a low virulence strain of IHNV (LV-IHNV). A small number of fish immunized with RecG_low orRecG_high possessed IHNV G protein specific antibodies (Abs) in their serum. Cumulative mortality (CM) of rainbow trout fry (mean weight, 1 g) vaccinated by i.p. injection of freeze/thawed Sf9 cells producing RecG_low was 18% ininitial trials following IHNV challenge. This level of protection was significant (p < 0.05) but was not long lasting, and neutralizing Abs were not detected in pooled serum samples. When trout fry (mean weight, 0.6 g) were vaccinated with supernatantcollected from sonicated Sf9 cells, Sf9 cells producing RecG_low, or Sf9 cells producing RecG_high, CM averaged 46%. Protection was enhanced over negative controls, but not the positive controls (2% CM), suggesting that in the firsttrial soluble cellular proteins may have provided some level of non-specific protection, regardless of recombinant protein expression. Although some immunity was elicited in fish, and RecG_low provided short-term protection from IHNV,Ab-mediated protection could not be demonstrated. The results suggest that recombinant G proteins produced in insect cells lack the immunogenicity associated with vaccination of fish with an attenuated strain of IHNV.

【 授权许可】

Unknown