Biochemical and cellular identification of HLA-Bw44 subtypes

Biochemical analysis of HLA-Bw44 antigens by two-dimensional gelelectrophoresis and one-dimensional isoelectric focusing (IEF) from serologically heterozygous and homozygous donors allows the identification of two distinct types of HLA-Bw44 molecules, designated as Bw44-I and Bw44-II. These results are in concordance with the data obtained by CML-typing where at least two types of Bw44 target cells can be distinguished clearly as well. The antigen of type I has a more acidic isoelectric point (IEP) than that of type II. The difference in IEP are not due to differences in sialic acid content.