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PubMed1989

Third-party-mediated graft rejection and graft-versus-host disease after T-cell-depleted bone marrow transplantation, as demonstrated by hypervariable DNA probes and HLA-DR polymorphism.

Graft rejection after marrow transplantation is generally thought to be mediated by alloreactive immune effector cells of host origin. Transfused blood products also contain immune cells capable of alloreactivity against both donor graft and host. To reduce the risk of transfusion-associated graft-versus-host disease (GVHD) and graft rejection, standard procedure is to irradiate all blood products with at least 1,500 rad before transfusion. We report a patient with chronic myelogenous leukemia who developed graft rejection and GVHD after receiving a T-cell-depleted transplant from a serologically HLA-A, B, DR/DQ matched and mixed lymphocyte culture (MLC) nonreactive unrelated donor. Cytogenetic analysis of marrow cells collected at the time of graft rejection revealed a PH1-negative female karyotype that was not consistent with donor cells. Use of specific minisatellite DNA probes (YNH 24, H-RAS, and 3' HVR) revealed the exclusive presence of third-party (neither donor nor recipient) restriction-fragment-length polymorphisms (RFLP) in both peripheral blood and marrow. Repeat RFLP analysis 3 days later showed persistence of this unique third-party banding pattern. DNA-based HLA-typing, using polymerase chain reaction (PCR) and oligonucleotide probe hybridization, also showed these cells to be derived from an individual whose HLA-DR type was distinct from donor and recipient. Together, these findings suggested the presence of a proliferating population of transfused cells possessing alloreactivity against both donor graft and host, despite prior irradiation of all blood products with 2,000 rad. Limiting dilution analysis to assess the frequency of irradiated lymphocytes able to respond to mitogen revealed an approximate 5- to 6-log reduction at 1,500 to 2,000 rad as compared with unirradiated controls. These data indicate that a small percentage of lymphocytes can survive irradiation at these doses and suggest that existing blood-product irradiation guidelines may require reassessment, especially in T-cell-depleted transplant recipients.

Bone Marrow Transplantation↗
PubMed1986

The HLA-DP polymorphism in Denmark investigated by local and international PLT reagents. Definition of two "new" DP antigens.

Lymphocytes from highly selected donors were primed for 10 days and subsequently bulk-expanded in IL 2 (TCGF) containing cultures. Two well-discriminatory PLT (CDP = Copenhagen DP) reagents against each of the DPw1-w6 specificities and one against each of the two "new" specificities, CDP4s and CDPHEI, were selected for further studies. Three combinations made in two recombinant families and four of ten HLA-A, B, and DR compatible combinations discriminated well in contrast to seven of 46 DR compatible, but HLA-A or B incompatible combinations. All reagents gave highly reproducible results, and high correlations (r-values between 0.73-1.00) for DP assignments were obtained with CDP and GNN reagents. No triplets were found for the DPw1-w6 and CDP HEI specificities. The "new" specificity CDP HEI defined in an HLA-DR/GLO recombinant family gave a coefficient of correlation with GNN 8 of 0.91. Another "new" specificity, CDP4s constitutes a subgroup ("split") of DPw4. The gene frequencies of DPw1-w6 estimated in 102 unrelated randomly selected Danes agreed with those reported for other Caucasoid populations. The gene frequencies CDP HEI and CDP4s were 0.03 and 0.08, respectively. The associations between DR3-DPw1, DR2-DPw4, and DRw6-DPw2 were confirmed. It is concluded that DP-typing with bulk-expanded reagents is a reliable and so far the only technique which can reveal the polymorphism of the DP gene products.

Cells, Cultured↗
PubMed1987

Conventional alloantisera can recognize the same HLA-B27 polymorphism as detected by cytotoxic T lymphocytes.

Subtypes of B27 have been identified by cytotoxic T lymphocytes, biochemistry, molecular biology, and murine monoclonal antibodies. In the present study we describe seven B27 subtype-specific pregnancy sera. The reaction pattern of these B27 subtype-specific sera closely parallels the recognition pattern of B27 subtype-specific cytotoxic T lymphocytes. Because the complete amino acid sequence of the studied B27 subtypes (B27W, B27K, B27C, B27D) is known, it can be determined which amino acid substitutions are responsible for recognition by subtype-specific sera and by cytotoxic T lymphocytes, respectively. It is proposed that B27 subtype-specific sera and B27 subtype-specific cytotoxic T lymphocytes recognize the same epitopes or that a single amino acid change can induce multiple antigenic determinants, which are recognized differentially by antibodies and T cells.

Amino Acid Sequence↗
PubMed2005

HLA-B polymorphism in Japanese HIV-1-infected long-term surviving hemophiliacs.

Approximately 30% of patients with hemophilia in Japan were infected with human immunodeficiency virus (HIV) in early 1980s through contaminated blood products. In 1995, a cohort of HIV-infected, asymptomatic patients with hemophilia was set up for follow-up study. Although the patients met the criteria for long-term non-progressor (LTNP) at the entry to the cohort, some of them later developed lymphopenia during five more years of observation. We collected blood samples from 80 long-term survivors; 42 of them did not require antiviral therapy, but the rest were under treatment. Analysis of HLA-B genotype revealed that carriers of known HIV-resistant alleles such as HLA-B*5701, B*5801, and alleles of B27 antigenic group were not increased in frequency, but that HLA-B*1507 was increased in the cohort (6.25% vs. 1.03%, OR = 6.40, p = 0.039). We also observed the decrease in carriers of HLA-B*5401 (3.75% vs. 14.95%, OR = 0.22, p = 0.016). HLAB* 5401 is a relatively common allele in East Asian populations and belongs to the same B22 antigenic group as B55 and B56 which were reported to associate with rapid progression. Our data indicated that HLA class I is one of the host factors involved in the retardation of HIV disease progression as also reported in the previous studies; however, the alleles associated with this resistance were not the same because of divergent host genetic background.

Alleles↗
PubMed2000

HLA class I polymorphism in the Albanian population.

The HLA class I polymorphism was studied in a sample of the Albanian population. Ninety-three unrelated healthy Albanians were typed for HLA-A, -B and -Cw antigens by standard microlyphocytotoxicity test. The antigens with the highest frequencies were: HLA-A2 (34.4%), A3 (14.5%) and A1 (12.4%); B51 (19.3%), B35 (12.4%) and B18 (10.2%); Cw4 (16.2%), Cw7 (16.2%) and Cw6 (10.8%). The HLA haplotypes with high frequency in Albanians included A2-B51 (4.3%), A2-B18 (2.4%), A2-B35 (2.4%), Cw4-B35 (7.6%), and Cw7-B18 (6.5%), which are not significantly different from the other neighboring populations. Low frequency of HLA-A1-B8 haplotype (1.1%) is noted in the Albanian population. The frequency of HLA-B27 antigen (1.1%) is one of the lowest frequencies observed in Caucasians. Such results are important in studies of HLA-A1-B8, HLA-B27 and disease associations. These findings should be also useful in understanding the origin of Albanians, representing a base for future studies about HLA polymorphism in the Albanian population.

Albania↗
PubMed1994

Analysis of overlapping T- and B-cell antigenic sites on rubella virus E1 envelope protein. Influence of HLA-DR4 polymorphism on T-cell clonal recognition.

A CTL antigenic site located between residues 273 and 291 of the E1 envelope protein of RV was identified by 51Cr-release assays employing SPs. Two E1-specific CTL clones were examined for immune recognition of RV wild-type and attenuated vaccine strains and recombinant E1 protein. The exact sequence (273-284) recognized by both clones was delineated by using truncated and overlapping SPs covering these residues. The defined T-cell site overlapped almost completely with a virus neutralizing antibody-binding site previously identified with mouse monoclonal and human antibodies. A series of single aa-substituted SP analogues of E1(273-284) was used to define residues critical for T-cell recognition. Using EBV-BL displaying different HLA-DR haplotypes and -DR4 subtypes as targets to determine MHC class II restriction elements, immune recognition by both T-cell clones was shown to be associated with HLA-DR4. Three HLA-DR4 subtypes (DR4Dw13A, DR4Dw13B, and DR4KT2) sharing a common residue, glutamic acid at position 74 in their beta 1 chains, were able to present SP E1(273-284) to the T-cell clones.

Amino Acid Sequence↗
PubMed1981

Analysis of HLA-DR polymorphism by two-dimensional peptide mapping.

Two-dimensional peptide mapping was used to study the polymorphism of DR antigens, membrane glycoproteins composed of two chains, alpha and beta, and encoded by the human major histocompatibility complex (MHC). Four DR antigens were purified by immunoabsorption from four human lymphoblastoid cell lines homozygous at the DR locus. After labeling with 125I, alpha and beta chains were separated by polyacrylamide gel electrophoresis in sodium dodecyl sulfate and digested with pepsin. Comparison of the peptide maps showed a marked degree of polymorphism among beta chains: only 43% of peptides were common to all four chains and 15-21% of the spots were unique to a given chain. By contrast, only a limited variability was observed among alpha chains. Homology was 75% for the four chains and the percentage of unique peptides was very low. DR7 did not possess even a single unique peptide. The limited variability among alpha chains and the lack of "private" peptides in one of them point to the conclusion that the beta chain is the unique carrier of the alloantigenic specificities. Higher homology within the known crossreactive groups was not observed, suggesting that the determinants responsible for crossreactivity are on different molecules. From a genetic point of view, because beta chains show allele-associated polymorphism, they are likely to be MHC encoded, whereas the minor differences among alpha chains do not allow a similar conclusion. The available data point to an analogy between these DR antigens and the mouse I-E/C antigens.

Alleles↗
PubMed2006

[Polymorphism distribution of HLA-DRB1 gene locus in Han race population in Liaoning of China].

OBJECTIVE: To elucidate the genotype distribution of HLA-DRB1 polymorphisms in the Han race population in Liaoning of China and to evaluate its value on forensic medicine. METHODS: The blood DNA samples from 13265 unrelated Chinese individuals of Han race population in Liaoning province were investigated and HLA-DRB1 alleles were genotyped with PCR-SSP and PCR-SSOP in low resolution level. RESULTS: Thirteen HLA-A alleles were found, in which HLA-DRB1*15, 09, 12, 07 were the commonest but HLA-DRB1*03(18), HLA-DRB1*14(8) were absent. The population data conformed to the Hardy-Weinberg equilibrium(chi-square was 73.34, df was 78, P> 0.5). The exclusion probability of paternity was 64.7%, the power of discrimination was 97.9% and the heterozygosity was 89.4%. CONCLUSION: The HLA-DRB1 polymorphism of Liaoning Han populations show the special characters and HLA-DRB1 genotyping is useful genetic marker to paternity testing and personal identification.

China↗
PubMed1996

HLA-DM gene polymorphisms in atopic dermatitis.

HLA-DM molecules are involved in the antigen-processing pathway of HLA class II-restricted antigen presentation. We investigated polymorphisms of HLA-DM genes in atopic dermatitis by using the polymerase chain reaction-restriction-fragment length polymorphism method to examine a possible contribution of these genes to the pathogenesis of atopic dermatitis. Genomic DNA was extracted from 37 Japanese patients with atopic dermatitis and 52 control subjects. After polymerase chain reaction amplification of the polymorphic third exon of DMA and DMB genes, amplified products were digested with restriction endonucleases to determine HLA-DM alleles. FokI, HinfI, AciI and SfaNI were used for DMA; HhaI, BsrI, ApaLI, and Bsp1286I for the DMB gene. We identified three DMA alleles and also three DMB alleles. One of 37 patients possessed the DMA*0103 allele, which has been reported as a rare allele in Caucasian populations. Any DMA and DMB alleles were not increased in the patients. The DMA*0102 allele was estimated to constitute a haplotype with DRB1*1201/DQB1*0301 and DRB1*0901/DQB1*0301 in a Japanese population. HLA-DM genes are not considered to contribute primarily to the susceptibility of atopic dermatitis. Further investigation of the functional roles of HLA-DM gene polymorphisms will be useful for a better understanding of susceptibility loci in HLA class II-associated disease.

Adolescent↗
PubMed1987

[HLA and molar pregnancies (triploidies, hydatidiform moles and choriocarcinoma). Etiological and epidemiological study].

Etiological and epidemiological studies of triploid and hydatidiform molar conceptuses were done using HLA polymorphism. The segregation of HLA markers allowed to know the etiology of 25 triploidies and 19 hydatidiform moles. Five other moles and a post molar choriocarcinoma were also studied by molecular hybridization. This confirms that triploidies in about 3/4 of the cases involved two sets of paternal chromosomes mainly by di-sperm. Hydatidiform moles from Algeria, France and Senegal were all of androgenic origin excepted for one case. DNA analysis of the choriocarcinoma demonstrated the presence of a paternal marker suggesting for this case a direct cellular lineage from the mole. Positive associations with HLA A 28 and B 7 were found which could be related to gametogenesis-fecundation dysfunction. A slight excess of antigens shared by parents of triploidies was shown. This was not observed for parents of hydatidiform moles but when they shared HLA antigens a preferential inheritance in the mole of the shared specificities was observed. This relative compatibility of the molar conceptus with the mother may be an element of the process that prevent its early rejection.

Choriocarcinoma↗
PubMed1994

HLA-DPB1 polymorphism in the Thais of Southeast Asia.

In this study we examined DPB1 allele frequencies in five ethnic Thai populations resident in different regions of Thailand and neighboring countries. In contrast to other Asian and Pacific populations such as the Japanese, Chinese, Korean, and Papua New Guineans, where DPB1*0501 has consistently been shown to be the most frequent allele, NE Thais and Thai-Khmers demonstrate a prevalence of DPB1*1301. Comparison of DPB1 allele frequencies in the Thais of SE Asia, with known frequencies in the Chinese and Japanese populations of E Asia, would appear to confirm previous calculations of genetic divergence between these Oriental populations.

Alleles↗
PubMed2005

Classification of human population based on HLA gene polymorphism and the concept of Prakriti in Ayurveda.

BACKGROUND: Correlating phenotypes with genotypes remains the major postgenomic challenge. Attempts to correlate phenotype characteristics associated with ethnicity, geographical divisions, or diseases to genotypes have had limited success. This means that current approaches for identifying phenotypes associated with haplotypes may be inadequate. OBJECTIVES: We hypothesize that a human phenome based on Ayurveda could provide an appropriate approach. Specifically, there could be a genetic basis for the three major constitutions (Prakriti) described in Ayurveda. The Prakriti classification is based on differences in physical, physiological, and psychologics characteristics and is independent of racial, ethnic, or geographical considerations. It may provide an appropriate means of classifying phenotypes to be considered collectively for genotyping. DESIGN: As a pilot study to test the hypothesis, we evaluated 76 subjects both for their Prakriti and human leucocyte antigen (HLA) DRB1 types. The genomic DNA was extracted using a standard protocol. Subsequently, HLA DRB1 typing was done by low-resolution polymerase chain reaction sequence specific primers and oligonucleotide probes. RESULTS: We observed a reasonable correlation between HLA type and Prakriti type. The complete absence of the HLA DRB1*02 allele in the Vata type and of HLA DRB1*13 in the Kapha type are significant, with X2 = 4.715 and p < 0.05. HLA DRB1*10 had higher allele frequency in the Kapha type than in the Pitta and Vata types. CONCLUSION: Ayurveda classifies the whole human population in three major constitutions as Vata, Pitta, Kapha and their possible combinations. Their homologous relation to human genetic structure needs to be studied for validation. If validated, our hypothesis would have far reaching implications for pharmacogenomics, modern genetics, human health, and Ayurveda.

Adult↗
PubMed1993

Evidence for a polymorphism of HLA-G gene.

HLA-G gene polymorphism was analyzed by RFLP using seven restriction enzymes and an HLA-G locus-specific probe. Hybridization of 55 DNAs digested with three enzymes (Taq I, Pst I, and Bgl II) revealed two polymorphic bands in each case. RFLP patterns obtained with Taq I and Pst I corresponded to the same allelic polymorphism and differed from the Bgl II polymorphism. Combining both polymorphisms enabled determination of four alleles. Allelic frequencies were calculated: 40% of the subjects tested had allele 1, 36% had allele 2, 22% had allele 3, and 2% had allele 4. Analyzing the complete HLA class I phenotype revealed strong linkage disequilibrium with the HLA-A locus. The polymorphism described is located in the 3' flanking region of the gene. Moreover, extended HLA-A haplotypes were constructed by combining the HLA-G polymorphism with other class-I-sequence polymorphisms.

Base Sequence↗
PubMed1989

RFLP-defined HLA-DP polymorphism in four ethnic groups.

Patterns of BglII, MspI, and TaqI DP alpha and DP beta hybridizing restriction fragment length polymorphisms are compared with primed lymphocyte typing--determined specificities in 28 10th International Histocompatibility Workshop core cell lines. Correlation of specific RFLP patterns with most recognized DP types is confirmed, although the RFLPs do not distinguish DPw3 from DPw6. Analysis of DP-region nucleotide sequence data shows that the observed RFLPs are those expected to hybridize to the DP alpha and beta probes and are thus not due to cross-hybridization to other genes. The distribution of RFLPs in Chinese, Micronesian, South Indian, and white Australian populations is described. The most frequent DP specificity in Chinese is DPw5. In the other populations DPw4 is the most common specificity, although DPw5 is also relatively common in Micronesians. Four new DP alpha RFLP patterns and three new DP beta patterns are described. There are also numerous unusual combinations of DP alpha and DP beta alleles particularly in the South Indian population.

Australia↗
PubMed2006

Class II HLA allele polymorphism: DRB1, DQB1 and DPB1 alleles and haplotypes in the New Zealand Maori population.

Class II alleles of interest to transplantation comprise the DRB1, DQB1 and DPB1 loci. Sequence-based typing was used to determine the class II allelic variability present in New Zealand Maori, a population with close genetic ties to Polynesia and known anthropological and linguistic connections to mainland Asia. The most common DRB1 alleles identified were DRB1*1201, DRB1*110101, DRB1*0403 and DRB1*080302, with frequencies of 21.5%, 14%, 11.25% and 9.25%, respectively. Standard linkages between the DRB1 locus and the DRB3, 4 and 5 loci were maintained, with no novel patterns identified. The most common DQB1 alleles identified were DQB1*030101, DQB1*060101, DQB1*020101, DQB1*0602 and DQB1*050201, with frequencies of 29.5%, 8%, 7.8%, 6.4% and 6.2%, respectively. The most common DPB1 alleles identified were DPB1*0501, DPB1*040101 and DPB1*020102, with frequencies of 40.2%, 28.89% and 15.83%, respectively. A total of 80 estimated DRB1-DQB1 two-locus haplotypes were detected. DRB1*1201-DQB1*030101 was the most frequent (15.40%) haplotype, followed by DRB1*110101-DQB1*030101 (9.97%), DRB1*0403-DQB1*030201 (7.37%) and DRB1*080302-DQB1*060101 (5.96%). The allelic variation determined is being used in further analysis of the requirement for bone marrow transplantation in the New Zealand Maori population and has implications for optimal ethnic donor distribution on the New Zealand Bone Marrow Donor Registry, anthropological studies and disease association.

Alleles↗
PubMed2002

Analysis of DNA polymorphism at HLA-A locus by PCR amplification with sequence specific oligonucleotide probe in Chinese Han and Uygur populations.

To determine HLA-A genetic polymorphism in Chinese populations and establish ethnic genetic database, 165 Han and 162 Uygur subjects were investigated with a non-isotopic and sensitive method PCR-SSOP. 22 alleles were identified in Han with the most frequent allele being HLA-A * 1101 (19.7%), followed by * 0201 (12.72%). Also, 22 alleles were identified in Uygur with * 2407 (17.90%) being the most frequent one and the frequencies of following alleles: * 0201, * 0101, * 3301 were higher than 10%. HLA-A * 0203, * 0205, * 0210, * 0302, * 2403 and * 3302 were only detected in Han; meanwhile * 0205, * 0211, * 2301, * 2502, * 68012 and * 6802 were only in Uygur. According to Hardy-Weinberg equilibrium, each allele showed no significant (P > 0.05) deviation between the expected frequency and the observed one. Heterozygosity (H), discrimination power (DP) and probability of paternity exclusion (EPP) of HLA-A locus from Han nationality were computed to be 0.9029, 0.9776 and 0.8592; and those from Uygur as 0.9063, 0.9379 and 0.7885. These results suggest that HLA-A DNA polymorphism and the database of two Chinese populations have useful applications in processing forensic casework (as personal identification, paternity test), tracing population migration and genetic diagnosis.

Alleles↗
PubMed2006

[Distribution of HLA-B allele polymorphism of 8962 Han population in Liaoning of China].

OBJECTIVE: To investigate the distribution of genetic polymorphism of HLA-B locus in Liaoning Han population. METHODS: The technique of polymerase chain reaction-sequence specific primers (PCR-SSP) was adopted in genotyping a sample of 8962 unrelated healthy individuals collected from a Chinese Han population in Liaoning area. The allele frequency of HLA-B was calculated and was compared with the results from other population. RESULTS: Thirty-four HLA-B alleles were detected. The more common HLA-B allele included B*15(14.42%), B*40(14.33%) and B*13(11.99%). The B*82 and B*83 were absent. Forty-nine HLA-B antigens were detected. CONCLUSION: The HLA-B allele polymorphism distribution of Liaoning Han population exhibits its own characteristic and the difference from old south and north Han population in China.

Alleles↗