HLA-B and HIV-1 infection: For example, coexpression of KIR3DS1 and its ligand HLA-B Bw4-80Ile alleles was associated with a delayed progression to AIDS in HIV-1-infected individuals, whereas the expression of KIR3DS1 in the absence of the HLA-B Bw4-80Ile alleles was not associated with a delayed clinical progression following HIV-1 infection [12].