A method of immunizing against HTLV-1 is disclosed. The method may include preparing a DNA sequence corresponding to a chimeric peptide which may have immunogenic epitopes of HTLV-1. These epitopes can include a Tax epitope, a gp21 epitope, a gp46 epitope, and/or a gag epitope. The method also includes production of the chimeric peptide using the DNA sequence and purifying the produced chimeric peptide. The purified chimeric peptide can be employed for immunization against HTLV-1.

This invention relates to the identification of peptide binding to ligands, and in particular to identification of epitopes expressed by microorganisms and by mammalian cells. The present invention provides polypeptides comprising the epitopes, and vaccines, antibodies and diagnostic products that utilize or are developed using the epitopes.

Described herein are Bovine immunodeficiency virus gag protein (Bgag) recombinant virus like particles (VLPs) comprising one or more different types of target pathogen proteins. Also described, are compositions comprising the novel Bgag VLPs and the methods of making and using the novel Bgag VLPs.

An object of the present invention is to provide a novel non-replicating bovine leukemia virus (BLV) and a producing cell thereof. According to the present invention, there is provided a bovine leukemia virus (BLV) in which at least a part of the function of a pol gene is deficient. Also, according to the present invention, there is provided a non-replicating BLV-producing cell comprising a gene of a BLV in which at least a part of the function of a pol gene is deficient. The present invention is advantageous in that it can provide a BLV vaccine which is highly immunogenic, and is highly safe without replicating in an infected subject.