C2 and autoimmune hepatitis: Because HLA-Cw5 molecules belong to KIR ligand group C2 and HLA-B18 molecules are classified as Bw6, AIH patients carrying the HLA-B18, Cw5, DR3 three-loci haplotype will obviously display marked differences with respect to the control population for the C1, C2, Bw4 and Bw6 ligand groups.