Bu--a new antigen at the HLA-B locus

Area of Science:

• Immunogenetics
• Human Leukocyte Antigen (HLA) system
• Population genetics

Background:

• The Human Leukocyte Antigen (HLA) system plays a crucial role in immune response and transplantation.
• The HLA-B locus is highly polymorphic and associated with various immune functions and diseases.
• Characterization of novel HLA alleles is essential for understanding immune diversity and compatibility.

Purpose of the Study:

• To report the discovery and initial characterization of a new HLA-B allele.
• To define a novel antigen, designated Bu, at the HLA-B locus.
• To investigate the population frequency, inheritance, and serological properties of the Bu antigen.

Main Methods:

• Population studies were conducted on English Caucasian individuals.
• Family studies involving at least three generations were performed to establish inheritance.
• Platelet absorption studies and analysis of multispecific HLA-B antisera were utilized for serological characterization.

Main Results:

• A new allele at the HLA-B locus defining the Bu antigen was identified.
• The gene frequency of the Bu antigen was determined to be 0.0043 in English Caucasians.
• Inheritance of Bu was confirmed in three informative families; no HLA-B locus triplets involving Bu were observed, and serological analysis suggested it is intermediate between Bw15 and Bw21.

Conclusions:

• The discovery of the Bu antigen expands the known allelic diversity of the HLA-B locus.
• The Bu antigen exhibits a specific gene frequency and inheritance pattern.
• Its serological profile suggests a close antigenic relationship with Bw15 and Bw21, contributing to HLA-B typing resolution.