Analysis of HLA allele-specific antibodies and Eplets in patients with platelet transfusion refractoriness / 中国输血杂志

【Objective】 To analyze the specificity and Eplets of HLA allele-specific antibody in patients with platelet transfusion refractoriness (PTR). 【Methods】 HLA-A and B genotypes were detected by PCR-SBT, and HLA-Ⅰ antibodies in patients′ serum were detected by Luminex single antigen beads coating method. IPD-IMGT/HLA Database was used to find the differential amino acids of allele-specific antibodies, and HLA Eplet database was used to analyze the registry Eplets. 【Results】 HLA allele-specific antibodies were found in 12 out of 82 patients with PTR.After sequence alignment, a total of 18 differential amino acids were found, such as 19E>19K, 166D>116E, 167G>167W and so on. Among these differential amino acids, 16 registry Eplets were retrieved such as 19E>19K, 95I>95L, 113YD>113HD and so on.The amino acid substitution of 166DG>166EW, 70Q>70H, 67S>67Y, 94I>94T, 82LR>82RG, and 211G>211A may form new Eplets that have not been registered.The antigens of A11, A24, B15, B27 and B38 can be further subdivided into HLA narrow specific antigens. 【Conclusion】 It was found that there were HLA allele-specific antibodies in patients with PTR, suggesting that high-resolution typing of HLA-A, B should be carried out for these patients and platelet donors in HLA compatible transfusion of PTR.

Distribution of HLA-A, B, C Allele and Haplotype Frequencies in Koreans / 대한진단검사의학회지

BACKGROUND: The HLA system is known to be the most polymorphic gene cluster in the human genome. HLA allele and haplotype distribution varies widely among different ethnic groups. In this study, we examined the frequency of HLA class I alleles and haplotypes in 309 healthy Koreans. METHODS: We typed HLA-A, -B, and -C genes at the allelic level in 109 unrelated Korean individuals using a sequence-based typing. With the additional data of 200 healthy Koreans from dbMHC (http: //www.ncbi.nlm.nih.gov/mhc/), allele and haplotype frequencies were estimated by the maximum likelihood method. Serological typing results of 49 individuals were compared with the results highly resolved. RESULTS: A total of 22 HLA-A, 41 HLA-B, and 21 HLA-C alleles were found in this study. Alleles showing frequencies of more than 10% in each HLA locus were A*2402 (22.5%), A*0201 (15.7%), A*3303 (14.4%), A*1101 (11.0%), B*5101 (12.1%), Cw*0102 (18.8%), and Cw*1402 (10.2%). The most common A-B-C haplotypes at a frequency of more than 3% were A*3303-B*5801-Cw*0302 (5.2%), A*2402-B*5101-Cw*1402 (4.5%), A*1101-B*1501-Cw*0401 (4.3%), A*3303-B*4403-Cw*1403 (4.0%), A*3001-B*1302-Cw*0602 (3.7%), and A*0207-B*4601-Cw*0102 (3.2%). Misassignment of HLA-C antigen by serotyping was detected in 11 (22.4%) of 49 individuals. CONCLUSIONS: Our results will be useful as a basic data for studies on anthropology, disease association, and bone marrow transplantation. Misidentification of HLA-C by serotyping is so high that it would be desirable to perform a DNA typing especially in unrelated bone marrow transplantation.

HLA-A, -B, -DR Allele Frequencies and Haplotypic Associations in Koreans Defined by Generic-Level DNA Typing / 대한진단검사의학회지

BACKGROUND: HLA allele and haplotype distribution varies widely among different ethnic groups. For organ transplantation, anthropology and disease association studies, reliable data on the HLA distribution in each ethnic group is needed. In recent years, more accurate DNA typing methods are increasingly used in place of the serologic typing method. METHODS: We examined HLA-A, -B, and -DR alleles at the generic (serologic) level in 1, 600 Koreans registered for the Korea Marrow Donor Program (KMDP) using the PCR-sequence specific oligonucleotide (SSO) method (Dynal RELI(TM) kit). Allele and haplotype frequencies were estimated by the maximum likelihood method using the computer program developed for the 11th International Histocompatibility Workshop. RESULTS: HLA alleles found in Koreans were 13 in A, 31 in B, and 13 in DR locus. Most frequent alleles with frequencies > or =10% were: A2, A24, A33, A11; B62, B44, B51; DR4, DR15, DR13, and DR8 in each locus in decreasing order of frequency. Subtype frequencies of B61 and B75 serologic specificities were identified: B*4002 (51.1%), *4003 (7.6%) and *4006 (41.3%) for B61, and B*1502 (9.5%) and *1511 (90.5%) for B75. Two-locus haplotypes with frequencies> or =0.1% were presented (99 A-B, 115 B-DR), among which those with frequencies> or =1.0% showing significant positive linkage disequilibrium (P or =0.1% were identified in Koreans, among which 38 haplotypes showed frequencies> or =0.5%. We compared the results of this study with those of our previous study of serologically typed HLA-A, -B and DNA typed HLA-DR in 2, 000 Koreans. Results from the two studies were similar, but blank frequencies were decreased to 0% for HLA-A, -B, and -DR locus compared with the frequencies of 0.3-0.8% in the previous study (A, 0.3%; B, 0.8%; DR, 0.3%) and all of the serologic splits could be assigned in this study. CONCLUSIONS: In this study, we provided the allele and haplotype frequencies of HLA-A, -B, and -DR in Koreans defined by a DNA typing method, which can be used as basic data on Koreans for organ transplantation and disease association studies.

Allele frequencies of HLA class I and HLA class II in the Vietnamese Kinh ethnic

Experimental study for extracting DNA and determining HLA of I and II class by PCR-SSO was carried out. The percentage of allele frequency was estimated in comparison with that was reported in 1991 conference. Result showed no difference in locus A and DR12. Locus A demonstrated the highest percentage with some differences of 2-4%. In Locus DR12 with the highest percentage of differences of 3%. Highest difference was estimated in locus B. In this study, B15 has 25.7% (in comparing with 0%). B62 had 0% (in comparing with 10.1%), B75 6.7% (in comparing with 0%), B7 12.2% (in comparing with 0%)