A point mutation in beta(2)-microglobulin results in loss of epitope expression

A common tool in studying the structure and function of major histocompatib ility complex: (MHC) class I is the generation and analysis of beta (2)-mic roglobulin (beta (2)m) mutations. beta (2)m has been shown to affect proper class I antigen presentation at the level of structural functionality. Man y studies characterizing beta (2)m function in class I presentation have us ed antibody-based assays. Monitoring the effect of beta (2)m mutation on an tibody epitope expression, therefore, is essential in being able to truly c haracterize the impact of a mutant interaction between beta (2)m and class I. Here we describe a mutant beta (2)m molecule, beta (2)m #32, that in ass ociation with class I loses reactivity with the human beta (2)m-specific mo noclonal antibody, BBM.1. However, the BBM.1 epitope remains intact when be ta (2)m #32 is free from class I association.