Demonstration of infectious salmon anaemia (ISA) viral antigens in cell cultures and tissue sections.

Rabbit polyclonal antibodies and mouse monoclonal antibodies (MAb) directed against infectious salmon anaemia virus (ISAV) were produced using a virus prepared in a newly established cell line culture developed from Atlantic salmon head kidney (SHK-1) cells. These antibodies were used to establish an indirect fluorescent antibody test for the detection of viral antigens in cell cultures and tissue cryosections. Specific fluorescence was detected in ISAV-infected cell cultures using rabbit polyclonal and MAb. One selected MAb produced specific staining for ISAV in the tissue sections from all the examined organs of ISAV-infected Atlantic salmon 20 d post infection. Fluorescence was mainly found in the endothelial cells and in single cells scattered throughout the parenchyma of the organs.