Mesoporous silica nanocarriers loaded with ribavirin against largemouth bass virus

Abstract

Largemouth bass virus (LMBV) has caused massive mortality in marine and freshwater animals worldwide, resulting in huge economic losses in aquaculture. Currently, rare methods for the treatment of LMBV are available for the lack of specific drugs and the restriction of biofilm barrier. Hence, developing alternative medications and efficient drug delivery strategies for the treatment of LMBV-related diseases is in demand. In this research, the anti-LMBV activity of ribavirin and mesoporous silica nanocarriers loaded with ribavirin (MSNs-R) was evaluated in vitro and in vivo. Ribavirin can efficiently protect EPC cells against LMBV infection, with half inhibitory concentration (IC50) values of 7.16 μM after 48 h of exposure. Similarly, ribavirin demonstrated potent anti-LMBV activity in largemouth bass, with 68.4% inhibition rate of LMBV after 7 days of continuous treatment. Furthermore, MSNs were exploited as drug carriers to enhance the anti-LMBV activity of ribavirin. An intelligent drug delivery system based on MSNs loaded with ribavirin was constructed and characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). MSNs-R was internalized in EPC cells and showed systemic dispersion in zebrafish larvae. And the cumulative survival rate of larvae treated with MSNs-R was 63.3% on the 7th day after infection, while that of the control group and naked ribavirin group was 3.3% and 40.0% respectively. The results to date demonstrated that ribavirin was an effective anti-LMBV drug and that MSNs could be promising candidate drug carriers for the treatment of LMBV-related diseases in aquaculture.