RNA in situ hybridization for the detection of feline immunodeficiency virus in infected cells

In the present study, we have applied a novel approach to generate specific digoxigenin- and biotin-labeled RNA probes to detect Feline Immunodeficiency Virus (FIV) gag gene in the FIV-infected feline T-lymphoblastoid cell line (MYA-1). This involved cloning of the FIV gag gene into a PCR Script vector containing both T3 and T7 promoters, followed by amplification of the insert and the two promoter sequences, using specific primer sequences. The FIV RNA probes were more sensitive than FIV DNA probes. This approach should make RNA in situ hybridization more accessible for use in routine diagnosis.