Comparative analysis of HLA-B 8101 by serology, isoelectric focusing, and sequence-based typing

We describe a bone marrow donor evaluation on a twenty-four-year-old patient from Honduras, Central America. The patient's phenotype included a HLA-B7v, with serologic reactivity to HLA- B7, 8101, and 48, and was consistent with, HLA-B*8101. One-dimensional isoelectric focusing (IEF) identified HLA-B 7.1, a low frequency isotype that has previously been associated with the HLA-B7 variant, B*0705. To further classify this allele, sequence based typing (SBT) was performed, confirming HLA-B*8101 sequence homology. The diagnostic evaluation of this case illustrates the correlation of sequenced based typing and isoelectric focusing in defining HLA Class I antigen characteristics and the use of IEF in screening for rare and novel alleles.