Bacterial nanocellulose vaccine loaded with glycoprotein can potentially protect Channa argus against SHVV

Snakehead vesiculovirus (SHVV) is a pathogen that causes severe economic losses in snakehead aquaculture, and effective control measures remain limited but are urgently needed. Vaccination, as a primary strategy for preventing aquatic diseases, has attracted broad interest. The glycoprotein of SHVV, a key virulence factor with high immunogenicity, represents a promising candidate for genetically engineered vaccines. This study used bacterial nanocellulose (BNC) as a new vaccine delivery carrier, and used a chemical linkage reaction to connect oxidatively modified BNC to a recombinant protein (rG) to construct the nanocarrier subunit vaccine BNC-rG. The prepared vaccine immunized snakehead via immersion, and the immune effect was evaluated through specific antibody levels, non-specific enzyme activity, and immune-related gene expression levels, combined with post-challenge viral load and relative percent survival (RPS). Compared to the control, the BNC-rG group exhibited significantly higher antibody levels in serum and mucus, as well as enhanced activities of acid phosphatase (ACP), alkaline phosphatase (AKP), and total antioxidant capacity (T-AOC). Furthermore, the expression of immune-related genes ( IFN-γ , IgM , IL-1β , IL-8 , MHC-I , and TNF-α ) in the spleen and head kidney of the BNC-rG vaccinated snakehead was significantly elevated. Additionally, the viral load in the BNC-rG group was considerably reduced 24 h post-challenge, and their RPS was 80.0%. The results show that BNC-rG can induce protective immunity in snakehead through immersion immunization, reduce the mortality of snakehead infected with SHVV, and help the healthy development of the snakehead breeding industry.