MICA Polymorphism, Linkage Disequilibrium with HLA-B and MICA Antibodies in Thai Kidney Transplant Recipients
Panpimon Luangtrakool MSc1, Sasijit Vejbaesya MD1, Komon Luangtrakool PhD1, Chutima Sermduangprateep MSc1
Affiliation : 1 Department of Transfusion Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
Background : The major histocompatibility complex class I chain-related gene A (MICA) is located in MHC class I region near HLA-B.
MICA is one of the polymorphic non-HLA antigens important in kidney transplantation. The information on the distribution of
MICA alleles and antibodies in Thai kidney transplant recipients is still lacking.
Objective : To determine MICA allele frequencies, their linkage with HLA-B and MICA antibody frequencies in Thai kidney transplant
recipients.
Materials and Methods : One hundred thirty Thai kidney transplant recipients were typed for MICA by PCR-SSP and HLA-B by
microlymphocytoxicity. There were 484 recipients tested for MICA antibody screening by LABScreen Mixed and for MICA antibody
speci(cid:976)icities by MICA single antigen kit. Allele frequencies of MICA, linkage disequilibrium with HLA-B and antibody frequencies
of MICA were analyzed.
Results : The four most frequent MICA alleles were MICA*008, *019, *010, *002. The most frequent MICA-HLA-B haplotypes were
MICA*010-B46, MICA*008-B60, MICA*019-B75, MICA*018-B18. The most frequent speci(cid:976)ic antibodies were MICA*007, *002, *001.
Conclusion : The polymorphism of MICA gene and strong linkage disequilibrium with HLA-B were found in Thai kidney transplant
recipients similar to the healthy Thais. The speci(cid:976)icities of MICA antibodies did not correlate with MICA alleles.
Keywords : MICA, Transplant, Thai
