Oral administration of white spot syndrome virus surface proteins VP24 and VP28 modulates immune gene expression in Penaeus monodon juveniles.

Being primitive organisms, crustaceans such as shrimp and crab rely on innate immunity to defend pathogens. White spot syndrome virus is a deadly pathogen that causes total mortality in farmed shrimp. Although shrimps do not possess an adaptive immune system and immune memory, there are efforts to prevent mass mortality due to WSSV through the administration of antigenic proteins derived from the virus. In this paper, we describe the effectiveness of the two major WSSV antigenic proteins, VP24 and VP28, in eliciting an immune response in shrimp. Recombinant proteins rVP28 and rVP24 were mass‐produced in E. coli and orally administered to Penaeus monodon juveniles. During the administration of recombinant antigens, differential expression analysis of shrimp biodefense genes was carried out. Among the genes analyzed, transcripts of TLR, Syntenin, PmRACK, Rab7, SOD and C‐type Lectin exhibited upregulation during the administration of both rVP28 and rVP24 at least at a one‐time point. Independently, rVP28 administration upregulated Lectin, PmRACK, Rab7, SOD, STAT, TLR and Syntenin genes at least at one‐time point. Penaeidin and Crustin are either downregulated or similar to that of control. The rVP24 administration upregulated Crustin, Lectin, Penaeidin, PmRACK, Rab7, SOD, TLR and Syntenin. The STAT was either downregulated or similar to that of the control at least at one‐time point. The results revealed the extent of the antigenic property and the ability of rVP28 and rVP24 to elicit an immune response after oral administration. [ABSTRACT FROM AUTHOR]