HLA-B and HIV-1 infection: Although HLA-B*57:01, HLA-B*57:03 and HLA-B*58:01 all associate with long-term non-progression of HIV-1 infection to acquired immunodeficiency syndrome21,22, differences in viral load between patients possessing different HLA-B57/58 alleles correlate with differential immunogenicity of identical peptide ligands23.