In vivo therapeutic efficacy of recombinant Penaeus monodon antiviral protein (rPmAV) administered in three different forms to WSSV infected Penaeus monodon

PmAV is the first antiviral gene identified from Penaeus monodon. The present study was performed to evaluate the therapeutic role of rPmAV in combating WSSV in P. monodon. The protective efficacy of rPmAV was tested in three different forms viz., purified rPmAV protein expressed in a fish cell line, plasmid DNA construct constitutively expressing rPmAV (pCMV-His-PmAV) and rPmAV expressing plasmid DNA encapsulated with chitosan nanoparticles. The challenge studies showed that pCMV-His-PmAV, chitosan-pCMV-His-PmAV nanoparticles and rPmAV protein (23.5 kD) injected intramuscularly into P. monodon gave survival rates of 27.8, 83.3 and 66.7%, respectively on fifteenth day post-WSSV challenge. The tissue distribution of the plasmid conjugate (chitosan-pcDNA-His-PmAV), which was injected intramuscularly at the ventral side of the shrimp, was traced at periodical intervals (2, 4, 8, 12 and 16 days post-injection) by PCR. The cmv fragment (830 bp) could be amplified from genomic DNA isolated from all the above tissues except gills up to 16th day which was the last day of testing. With this it can be concluded that rPmAV is an effective therapeutic molecule to control WSSV in shrimp provided that detailed studies regarding the best delivery strategy and optimum dosage are carried out.

► The protective efficacy of rPmAV (3 forms) in WSSV infected P. monodon was tested.
► Chitosan-pCMV-His-PmAV nanoparticles gave survival rate of 83.3% on 15th d.p.i.
► rPmAV protein expressed in FHM cell line gave survival rate of 66.7%.
► rPmAV can be used as therapeutic molecule in vivo in WSSV infected shrimp.