PCT No. PCT / CA95 / 00483 Sec. 371 Date Jun. 2, 1997 Sec. 102(e) Date Jun. 2, 1997 PCT Filed Aug. 15, 1995 PCT Pub. No. WO96 / 05292 PCT Pub. Date Feb. 22, 1996The present invention is concerned with the ability to differentiate between infection by HIV and immunization with an immunogenic preparation. Accordingly, the present invention provides a non-infectious, non-replicating, HIV
retrovirus-like particle containing a
heterologous antigenic marker, comprising an
assembly of (a) an env
gene product; (b) a pol
gene product; (c) a gag
gene product; and, (d) at least one non-retroviral, non-mammalian antigenic marker. The antigenic marker may have between 10 and 75
amino acid residues. In one embodiment, the
amino acid sequence contains a
tobacco mosaic virus (TMV)
epitope obtained from the
coat protein. In another embodiment, the marker is inserted into the gag
gene product at an antigenically-active
insertion site. The presence of the antigenic marker enables recognition that
antiserum containing anti-HIV antibodies has been generated by
exposure to the non-infectious
retrovirus-like particles, as opposed to wild-type HIV infection, by testing for antibodies specific to the antigenic marker.