In vitro neutralization by monoclonal antibodies against yellow grouper nervous necrosis virus (YGNNV) and immunolocalization of virus infection in yellow grouper, Epinephelus awoara (Temminck & Schlegel)

Mouse monoclonal antibodies (MAbs) were produced by using yellow grouper ne rvous necrosis virus (YGNNV) as an immunogen, isolated from infected yellow grouper, Epinephelus awoara (Temminck & Schlegel), and propagated in GB ce lls. In enzyme linked immunosorbent assay (ELISA), 43 hybridoma clones secr eting MAbs strongly reacted with the purified virus. Ten of them showed a h igher neutralization index (NI) value between 6.5 and 4.5 (log(10) NI) than the other 33 MAbs against YGNNV infection in cell culture. All 10 MAbs bel onged to the IgG isotype with a kappa light chain and recognized the 42 kDa coat protein of YGNNV by Western blot analysis. Immunohistochemical result s demonstrated that the viral signals co-located with pathological lesions observed in retina, brain and spinal cord. These results indicate that the MAbs are useful for confirmative diagnosis of YGNNV infection.