Molecular tissue typing in renal transplantation: Initial experience from a tertiary care Naval Hospital

BACKGROUND: During the last five years the proportion of HLA matching is relevant for cadaver kidney allocation of living unrelated kidney transplants has increased and and in living donor selection if choice for donors with DNA tissue-typing methods have become popular in India. better match is available. In India however, due to paucity This study was carried out to compare the results of tissue typing by serology and sequence specific primers (SSP) of cadaver kidneys, the choice of donors is rather limited. and study the usefulness of ‘episode’ allograft biopsies for Most tissue-typing laboratories commence HLA typing diagnosis of acute graft dysfunction. by serology and then gradually adopt molecular methods MATERIALS AND METHODS: DNA was extracted from whole blood using Qiagen kit. Samples from 60 individuals first for class II and subsequently for class I. In renal including thirty patients and their donors were typed by transplantation, low or medium-resolution tissue-typing serology and SSP. Fifteen allograft biopsies were performed for suspected acute rejection (AR) cases. is adequate, whereas in unrelated BMT it is always RESULTS: Both alleles of HLA A, B and DR antigen could followed with high-resolution typing. be determined in 86, 65 and 90% of samples by SSP respectively. There was a discrepancy of 16-40% between SSP and serology. Acute rejection was confirmed in 8/15 Materials and Methods biopsies. Graft survival rates were 83 and 76% at one and two years respectively. Neither the graft survival nor the number of AR episodes showed any correlation with the This study was done at a government hospital during extent of HLA mismatch. SSP was useful in defining A*68, A*66, A*69 and A*33 alleles at private level and A*36, A*74 the period August 2002 to September 2004. All potential and A*03 alleles which were blank on serology. donors (n=30) were subjected to a thorough medical CONCLUSIONS: SSP has become popular in India due to check-up after which approval from Directorate of its simplicity, superior results especially for class II HLA alleles: and episode allograft biopsy is adequate for followMedical and Scientific Research; Maharashtra up of kidney recipients. Government was obtained for all transplantations.