Amplification of Enterocytozoon hepatopenaei in Penaeus vannamei Hepatopancreas Primary Culture and Immunofluorescence Assay for Detection of Enterocytozoon hepatopenaei

Abstract

Hepatopancreatic microsporidiosis (HPM) disease leads to retarded growth in shrimp resulting in a major loss for the shrimp industry worldwide. The causative agent of HPM is a microsporidian known as Enterocytozoon hepatopenaei (EHP). It is little understood how EHP infects its host and hijacks its cellular machinery to replicate more organisms. Lack of an immortal cell line is a bottleneck in studying the cellular and molecular basis of EHP infection in shrimp. For this reason, EHP cannot be propagated in in vitro culture and must be propagated in live shrimp. The use of live EHP-infected shrimp remains the only way to study EHP infectivity. It was hypothesized that supplementing EHP with fresh host cells will aid the propagation of EHP in vitro. Further research must be done but with the data collected at this point, this hypothesis is rejected. In addition to the challenges in amplifying EHP in in vitro culture, there is no antibody-based detection method for EHP. EHP infection in a shrimp is examined by Hematoxylin and Eosin (H&E) histology and real-time polymerase chain reaction based detection methods. Monoclonal antibodies that were previously characterized by Riggs and colleagues to detect Cryptosporidium parvum (C. parvum), successfully detected other parasites. Based on this, it was hypothesized that monoclonal antibodies against C. parvum may also detect EHP.