Two common nanoparticles exert immunostimulatory and protective effects in Tegillarca granosa against Vibrio parahaemolyticus

There are many studies revealed that metal-based nanoparticles (NPs) possess excellent bactericidal effect on multitudinous bacteria and fungi. However, the control effect of NPs as antimicrobial agents to against Vibrio parahaemolyticus infection remain in poorly understood for blood clam, Tegillarca granosa. In order to evaluate the effect, the changes in six physiological parameters and the immune-related genes expression of clams exposed to V. parahaemolyticus alone or along with NPs (nZnO or nCuO) were investigated in present study. Results showed that both tested NPs exerted prominent redemptive or mitigative effect in an inverse dose-dependent way on physiological indexes of clam, especially in the total counts, phagocytosis and the cell viability of haemocytes, as well as the concentration and activity of lysozymes, when co-exposed with Vibrio. Gene expression analysis showed NPs at a concentration of 0.1 mg/L generally mitigated the downregulation of immune-related genes after clam exposure to V. parahaemolyticus. The combination of 0.1 mg/mL nZnO and nCuO additives has been shown to significantly enhance the humoral immunity of blood clam, suggesting its potential as a protective measure against V. parahaemolyticus infection in T. granosa.

Automated summary

Many studies have shown that metal-based nanoparticles (NPs) have excellent bactericidal effects on various bacteria and fungi. However, the effectiveness of NPs as antimicrobial agents against Vibrio parahaemolyticus infection in blood clam, Tegillarca granosa, is poorly understood. In this study, the effect of NPs (nZnO or nCuO) on physiological parameters and immune-related gene expression in clams exposed to V. parahaemolyticus was investigated. The results showed that both NPs had a dose-dependent effect on physiological indexes of clams, especially in terms of their immune responses, when co-exposed with Vibrio. Gene expression analysis also revealed that NPs at a concentration of 0.1 mg/L mitigated the downregulation of immune-related genes after clam exposure to V. parahaemolyticus. The combination of 0.1 mg/mL nZnO and nCuO additives significantly enhanced the humoral immunity of blood clam, indicating its potential as a protective measure against V. parahaemolyticus infection in T. granosa.