A point mutation in beta2-microglobulin results in loss of epitope expression

C Dimaano1, T Nguyen, A Ahmed

  • 1Department of Biological Sciences, California State University, Hayward 94542, USA.

Tissue Antigens
|January 6, 2001
PubMed

A common tool in studying the structure and function of major histocompatibility complex: (MHC) class I is the generation and analysis of beta2-microglobulin (beta2m) mutations. beta2m has been shown to affect proper class I antigen presentation at the level of structural functionality. Many studies characterizing beta2m function in class I presentation have used antibody-based assays. Monitoring the effect of beta2m mutation on antibody epitope expression, therefore, is essential in being able to truly characterize the impact of a mutant interaction between beta2m and class I. Here we describe a mutant beta2m molecule, beta2m #32, that in association with class I loses reactivity with the human beta2m-specific monoclonal antibody, BBM.1. However, the BBM.1 epitope remains intact when beta2m #32 is free from class I association.

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