Screening for antibodies against MICA by Luminex flow cytometry

Antibodies against MICA have been found in organ transplant recipients and were found to be associated with decreased survival of kidney allografts. The MICA antibody screening assay is a Luminex-based solid phase immunoassay designed to detect IgG antibodies binding to beads pre-coated with recombinant preparations of MICA alleles. These beads coated with soluble MICA recombinant proteins including 11 common alleles have been produced in our laboratory and similar preparations have been available from commercial sources. Here, we describe the procedure of MICA antibody screening with a prepared kit, in which all the reagents were optimized and standardized. We also review how to document the quality of single MICA antigen beads using MICA-specific monoclonal antibodies, as well as quality control of the procedure and data analysis.