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Aim:To determine whether there is an immunogenic connection and antigen difference between the HLA antigens in the erosive (EOLP) and reticular (ROLP) oral lichen planus. Materials and Method: 73 patients with ROLP and EOLP have been tested. Typing of the HLA antigens has been made for locus A and B. The typing of the HLA was conducted with the use of microlymphocyto toxic test by Terasaki. The reading of the findings has been conducted with an inverse microscope. When a reaction has 4 points it is considered to be positive. Results: The most frequently typified antigens in ROLP from locus A are HLA А2 (57.57%) and А3 (33.33)%, and for locus B 21.21%. In EOLP it is А9 (8888%). In locus B a connection has been found with HLA B8 (77.77%). The statistical analysis with the ×2 test has shown that the carriers of HLA A9 display a relative risk (RR) of 3.65 and ×2=20.72. Consequently, there is high static importance for locus A p Conclusions: In ROLP A3 antigen and in EOLP A9 and A8 may be considered as carriers with proneness to OLP.

Analyses on reactivity of anti-cancer cytotoxic T lymphocytes (CTLs) and clinical application of peptide-based anti-cancer vaccine have been mainly focused on patients with HLA-A2 or -A24 alleles. In this study, we identified an enhancer of zeste homolog (EZH) 2-derived peptide applicable for anti-cancer vaccine for prostate cancer patients with HLA-A3 supertype alleles. Five EZH2-derived peptides that were prepared based on the binding motif to the HLA-A3 supertype alleles (HLA-A11, -A31, and -A33) were functionally screened for their potential to induce peptide-specific CTLs from peripheral blood mononuclear cells (PBMCs) of HLA-A3 supertype allele(+) prostate cancer patients. As a result, EZH2733-741 peptide was found to efficiently induce peptide-specific CTLs. The EZH2733-741 peptide-stimulated and purified CD8(+) T cells from PBMCs of HLA-A3 supertype allele(+) prostate cancer patients showed higher cytotoxicity against HLA-A3 supertype allele-expressing LNCaP prostate cancer cells than against parental LNCaP cells. This cytotoxicity against HLA-A3 supertype allele-expressing LNCaP cells was partially but significantly inhibited by the addition of EZH2733-741 peptide-pulsed competitive cells. These results indicate that the EZH2733-741 peptide could be a promising candidate for peptide-based immunotherapy for HLA-A3 supertype allele(+) prostate cancer patients.

Background: The haemochromatosis mutation C282Y occurred once in a person who lived in Ireland or Scandinavia and carried either human leucocyte antigen (HLA)-A3-B7 or A3-B14. With time, recombinations are believed to have taken place introducing new HLA haplotypes. This evolution is mainly unknown. In this study, we tried to find a founder, possible recombination events and effect on the phenotype in descendants. Setting: A Swedish mountain population close to Norway, n = 3529, population density

Multiple sclerosis (MS) occurs most frequently in northern and central Europe, the north of the United States, and Canada; it is more rare in China and Japan. Population studies showed association between HLA-A3, B7, Dw2, and DR2 with MS. There was a close association of MS with HLA-Dw2 and DR2, and the increased frequencies of A3 and B7 were secondary to linkage disequilibrium of B7 with Dw2, and of A3 with B7 in Caucasians. Black American MS patients showed a slight association with Dw2. In Japan, there was an association between MS and Dw6. The HLA pattern in optic neuritis (ON) patients failed between that of MS patients and healthy controls; ON only progressed to MS if the immunogenetic terrain was favourable.

Sixty-six idiopathic hemochromatotic French patients were HLA-A, B typed. The previously known strong association with A3 was confirmed (RR = 10.6, P less 10(-9)) and our results indicate clearly that a gene implicated in idiopathic hemochromatosis (IH) determinism is located in the HLA-A region. The linkage disequilibrium between A3 and B7 was found to be far greater in IH patients than in controls. The authors have therefore hypothesized that this might be due to a selective advantage of this haplotype in IH. The A3, B7, Dw2 HLA haplotype has been shown to exert a protective effect against common insulin dependent diabetes (IDD). Thus the patients were divided into two groups according to the presence or absence of a definite IDD. B7 was found more frequently in IH patients without IDD but the difference is not significant. In this context, the strong linkage disequilibrium between A3 and B7 might be due to the protective effect of the B region of this haplotype against IH secondary IDD.

Immunization of balb/c mice with peripheral blood mononuclear cells of a leukemic patient possessing the antigens HLA-A2,3; B7,35 resulted in the polymorphic monoclonal antibody (moab) UL-101/68 (IgM) defining HLA-A3. Immunization of a second group of balb/c mice with the lymphoblastoid cell line BER homozygous for HLA-A2; B13 revealed two polymorphic moabs UL-39/10 (IgG3) specific for HLA-B13 and UL-39/24 (IgG2b) defining HLA-A2,w69. Immunoprecipitation and polyacrylamide gel electrophoresis with the two moabs of the IgG isotype confirmed the class I structure of the recognized antigens.

KEYWORDS SLE; autoimmune antibodies; HLA; organ involvement ABSTRACT To determine the autoimmune status and HLA allele distribution in SLE patients confirmed on serological and clinical grounds and compared with normal age matched ethnic control population from Mumbai. HLA A, B serological typing were carried out in 53 unrelated SLE patients and 110 healthy controls. Autoantibodies were detected by indirect immunofluorescence and ELISA techniques. The autoantibodies directed towards ANF, anti Sm, AHA were increased among the major organ involved patients while the antibodies like anti - dsDNA, anti - ssDNA, anti - nRNP, anti - SSA (Ro), anti - SSA (La) and RF were increased among the other patients with minor organ involvement. HLA A1, A2, and B27 alleles were positively associated, while HLA A19, and B15 alleles were negatively associated among the total SLE patients when compared to normal controls. It was further interesting to note that among the major organ involved severe patients A3, A28, and B7 where increased while A11, A19 and B17 were decreased. Among the minor organ involved patients it was A1, A2, A26, B5, B40 and B56 which were increased while A11, A28 and B7 were decreased. A significant twofold increase in the odds ratio for HLA A3, A28 and B27 alleles with increased Ro, La, Sm and ds DNA autoantibodies was observed when compared to controls. A significant twofold decrease in the odds ratio for HLA A19, A11, B7 and B15 alleles with decreased Ro, La, Sm and ds DNA autoantibodies was observed, when compared to normal controls suggesting the positive and negative associations of these HLA alleles among the SLE patients from Mumbai.

HER-2/neu oncoprotein contains several major histocompatibility complex class I-restricted epitopes, which are recognised by cytotoxic T lymphocyte (CTL) on autologous tumours and therefore can be used in immune-based cancer therapies. Of these, the most extensively studied is HER-2(9(369)). In the present report, we used dendritic cells pulsed with HER-2(9(369)) to stimulate, in the presence of IL-7 and IL-12, the production of IFN-gamma by patients' CTL detected by the enzyme-linked immunosorbent spot-assay. Frequencies of peptide-specific precursors were estimated in HLA-A2, HLA-A3 and HLA-A26 patients with HER-2/neu-positive (+) breast, ovarian, lung, colorectal and prostate cancers and healthy individuals. We found increased percentages of such precursors in HLA-A2 (25%) and HLA-A26 (30%) patients, which were significantly higher (60%) in HLA-A3 patients. Our results demonstrate for the first time that pre-existing immunity to HER-2(9(369)) occurs in patients with colorectal, lung and prostate cancer. They also suggest that HER-2(9(369)) can be recognised by CTL, besides HLA-A2, also in the context of HLA-A3 and HLA-A26, thus increasing the applicability of HER-2(9(369))-based vaccinations in a considerably broader patients' population., Journal Article, Research Support, Non-U.S. Gov't, info:eu-repo/semantics/published

Epitope identification is the basis of modern vaccine design. The present paper studied the supermotif of the HLA-A3 superfamily, using comparative molecular similarity indices analysis (CoMSIA). Four alleles with high phenotype frequencies were used: A*1101, A*0301, A*3101 and A*6801. Five physicochemical properties—steric bulk, electrostatic potential, local hydro-phobicity, hydrogen-bond donor and acceptor abilities—were considered and ‘all fields’ models were produced for each of the alleles. The models have a moderate level of predictivity and there is a good correlation between the data. A revised HLA-A3 supermotif was defined based on the comparison of favoured and disfavoured properties for each position of the MHC bound peptide. The present study demonstrated that CoMSIA is an effective tool for studying peptide–MHC interactions.

Activation of a cytotoxic T cell requires specific binding of antigenic peptides to major histocompatibility complex (MHC) molecules. This paper reports a study of peptides binding to members of the HLA-A3 superfamily using a recently developed 2D-QSAR method, called the additive method. Four alleles with high phenotype frequency were included in the study: A*0301, A*1101, A*3101 and A*6801. The influence of each of the 20 amino acids at each position of the peptide on binding was studied. A refined A3 supertype motif was defined in the study.

Summary No monoclonal antibodies (mAbs) are presently available to measure the total amount of β2-microglobulin-free HLA class I heavy chain (FHC) in sera. The available ELISA-based double determinant immunoassay (DDIA), established to measure FHC, uses two mAbs (TP25.99 and HC-10) that recognize a monomorphic determinant expressed on all HLA-B/C FHC products and a determinant expressed only on some HLA-A FHC products. This restricted reactivity implies that, in addition to HLA-B/C, HLA-A FHC products are also detected in individuals bearing HLA A3 and/or A30 allotypes. The aim of this study was to establish whether such restriction results in the detection of low FHC levels in individuals lacking HLA A3 and/or A30 allospecificities. The FHC mean concentration (± SD) in 294 healthy blood/bone marrow donors (HBDs) was 0.24 (± 0.2) mg/l. The grouping of HBDs according to their HLA-A FHC product reactivity with one, both or no mAbs did not result in any statistically significant differences (Mann–Whitney test: P > 0.05) between their median FHC concentrations. Since the absence of differences in their FHC levels was not attributable to a difference in the percentage distribution of HLA allotypes associated with high or low HLA-B/C FHC expression, our results indicate that FHC HLA A3 and/or A30 products detected in DDIA by these two mAbs only minimally contribute to FHC serum expression and that the assay is not limited by the failure to detect HLA-A FHC products in A3− and/or A30− individuals.

Immunogenetic studies in various diseases provide potential genetic markers. We have studied the incidence of HLA A, B, C, DR and DQ loci antigen in Rh (D) antigen isoimmunized mothers compared to those nonimmunized isoimmunized Rh negative mothers. Seventy six mothers who were immunized to Rh (D) antigen due to pregnancy (responders) and fifty four mothers who did not develop Rh (D) isoimmunization despite positive pregnancies (nonresponders) were selected for the study. Standard methods of serological HLA typing, ABO and Rh (D) groups, and screening for Rh D antibodies were used. 392 unrelated individuals from the population were compared as controls. In addition 45 unrelated individuals from the same population were typed for HLA DRB and DQB gene using PCR-SSP kits. The genotype frequencies of HLA A2, A3, A28, B13, B17, B35, B52, B60, Cw2, Cw6, DR4, and DQ3 were significantly increased, while the frequencies of the HLA A11, A29, A31, B7, B37, B51, Cw1 and DR9 were decreased in the responder women when compared to the non-responder women. HLA A30 (19) split antigen was not identified in immunized women while HLA A23 (9) split antigen was not identified in non immunized women. HLA A3, B17, Cw2 and DR4 showed a significant relative risk among the immunized responder women. When compared with Rh immunized women (responders) reported from USA, England and Hungary the phenotype frequencies of HLA A11, A24, A28, B5, B17, B40, DR2 and DR5 were increased while HLA A23, B8, B18, and DR6 were decreased in the Indian Rh immunized women. Two locus haplotype frequency analysis observed among the responders women revealed that among the significant haplotypes expressed A2-B5, B7-Cw1, DR2-DQ1 were highly significant haplotypes in positive linkage, while A1-B5, and A1-B7 were in significant negative linkage disequilibrium. The haplotype frequencies were

Two hundred and eighty nine unrelated Marathas residing in Mumbai, Maharastra, (Western In- dia) were studied for HLA A, B, C and DR locus antigen profiles. The HLA antigen maximum likelihood gene fre- quencies of HLA A1, A2, A9 (24), A11, A19 (33), B5, B7, B35, B40 (61), Cw3, Cw6, DR2, DR5, DR7, DQ1 and DQ2 were increased while that of HLA A3, A10 (26), A36, B8, B13, B16 (38), B18, B21, B22 (55), B53, B73, Cw5, Cw7, DR3, DR4, DR9, and DQ3 were decreased in the Marathas. HLA antigens A25 (10), B14, B39 (16), B54 (22), B56 (22), B58 (17) and Cw8 were not identi- fied in the present investigation. Two Locus haplotype analyses revealed the presence of A10-B8, A1-B17, A24- B52, B5-Cw9, B13-Cw3, B15-Cw2, B35-Cw4, DR2-DQ1, DR5-DQ3 and DR1-DQ9 haplotypes with positive link- age disequilibrium among the marathas. Haplotype A2- B12 was the only haplotype identified in negative link- age disequilibrium. The observed maximum likelihood gene frequencies, haplotype frequencies and linkage dis- equilibrium in Marathas suggest the influence of genetic drift caused by selection, geography and culture. Further the study reveals that the Hindu population of India can- not be considered as a single panmictic population due to vast allelic diversity and immense heterozygosity in haplotypes.

To fully characterize human glutamic acid decarboxylase (GAD)65 protein T-cell epitopes associated with insulin-dependent diabetes mellitus (IDDM), CTL clones specific to GAD65 protein antigens were isolated from two congenital rubella syndrome (CRS)-associated IDDM patients. Overlapping nonamer T-cell epitopes recognized by both CD4 + or CD8 + CTL clones within peptides GAD65(252-266) and GAD65(274-286) were identified as sequences bounded by GAD65(255-266) with 6/9 overlapping residues, and GAD65(276-285) with 8/9 overlapping residues, respectively, using two panels of overlapping peptide analogs in cytotoxicity assays. HLA restrictive elements of the T-cell clones were also identified using a panel of B cell lines with different HLA phenotypes as targets in cytotoxicity assays. The antigenic GAD65 peptides elicited cytotoxic responses of peptide-specific CD4 + T-cell clones in the context of HLA DRB1∗0404. The CD8 + T-cell clone specific to GAD65(255-263) was found to be restricted by HLA A3 and A11. Similarly, the CD8 + T-cell clone specific to GAD65(277-285) killed peptide-sensitized target cells expressing HLA B35 and B15. The observed HLA restriction of these overlapping epitopes implies that a tandem of [DRB1∗0404-A11(3)] and/or a tandem of [DRB1∗0404-B35(15)] might predispose CRS patients to development of IDDM.

In a control population of 127 healthy adults in the West of Ireland, the possession of the HLA-antigens associated with idiopathic haemochromatosis (IH), i.e. HLA-A3, B7 and B14 was not accompanied by higher levels of serum iron, total iron binding capacity (TIBC) or transferrin saturation (TS%). HLA-A3 does not appear to confer enhanced ability to absorb dietary iron.

The HLA-B47, DR7 haplotype in congenital adrenal hyperplasia (CAH) due to 21–hydroxylase deficiency contains a deletion of most of the active CYP21 gene and the entire adjacent C4B gene. The C4A gene produces a protein which is electrophoretically C4A but anti-genically C4B. In the Old Order Amish, the HLA-B47. DR7 haplotype contains no deletion, but is immunologically identical to the CAH haplotype in both areas flanking the crossover region. We compared some of the genes in the MHC Class II and Class III regions in the Amish and CAH-linked haplotypes to define further the relationships between the two. The complement factor B (Bf) proteins differed, but no Bf RFLPs were identified. The complement factor 2 genes exhibited different BamHI RFLPs. Analyses of the tumor necrosis factor-α genes revealed the same Ncol restriction patterns. The RD genes contained microsatellites of the same size. Portions of the MHC Class II DR and DQ, and Class III CYP21 and C4 alleles were sequenced. The exon 2 sequences of DQ2 and DR7 were identical in the two haplotypes. In the Amish haplotype, both CYP21 and C4 gene pairs were present and functionally normal. The CAH haplotype had two sequence crossovers: from CYP21P to CYP21 in the 7th intron, and from C4A to C4B between codons 1106 (exon 26) and 1157 (exon 28). A model is proposed which accounts for the CAH-linked mutant haplotype arising from a nonmutant homologue via three crossings-over.

The large majority of known melanoma-associated antigenic peptides presented by MHC class I molecules are presented by the most frequent allele, HLA-A*0201. Thus although a significant percentage of Caucasians express HLA-A3, no melanoma-associated antigenic peptide presented by this allele has yet been identified. We show here that the T cell clone M45-10 isolated from tumor infiltrating lymphocytes recovered from a melanoma biopsy recognizes the gp100-derived peptide ALLAVGATK presented by HLA-A*0301. Since gp100 is expressed on most melanoma cells, our results imply that the gp100-based anti-melanoma strategies developed for individuals expressing HLA-A2 will also be applicable to those expressing HLA-AS (about one Caucasian in four). gp100 is therefore a particularly promising melanoma antigen, as different peptides derived from it can be presented by at least two different frequently encountered HLA class I molecules.

The Simian immunodeficiency virus (SIV)-infected Indian rhesus macaque (Macaca mulatta) is the most established model of HIV infection and AIDS-related research, despite the potential that macaques of Chinese origin is a more relevant model. Ongoing efforts to further characterize the Chinese rhesus macaques’ major histocompatibility complex (MHC) for composition and function should facilitate greater utilization of the species. Previous studies have demonstrated that Chinese-origin M. mulatta (Mamu) class I alleles are more polymorphic than their Indian counterparts, perhaps inferring a model more representative of human MHC, human leukocyte antigen (HLA). Furthermore, the Chinese rhesus macaque class I allele Mamu-A1*02201, the most frequent allele thus far identified, has recently been characterized and shown to be an HLA-B7 supertype analog, the most frequent supertype in human populations. In this study, we have characterized two additional alleles expressed with high frequency in Chinese rhesus macaques, Mamu-A1*02601 and Mamu-B*08301. Upon the development of MHC–peptide-binding assays and definition of their associated motifs, we reveal that these Mamu alleles share peptide-binding characteristics with the HLA-A2 and HLA-A3 supertypes, respectively, the next most frequent human supertypes after HLA-B7. These data suggest that Chinese rhesus macaques may indeed be a more representative model of HLA gene diversity and function as compared to the species of Indian origin and therefore a better model for investigating human immune responses. Electronic supplementary material The online version of this article (doi:10.1007/s00251-010-0502-8) contains supplementary material, which is available to authorized users.

International audience; Anti-HLA antibody (Ab) monitoring is essential for the follow-up of transplant patients. However, it can be affected by drugs, especially Ab infused as a conditioning regimen for transplantation. ATG Fresenius, commonly used in this setting, is a polyclonal rabbit Ab raised against the Jurkat human T cell line (HLA-A3, 32; B7, 35). We report here the de novo detection by CDC and flow cytometry (Luminex) of anti-HLA-A3 Ab in the serum of kidney recipients treated with ATG Fresenius. The Ab, of rabbit origin, was detected in every assessable patient (n = 16), with the exception of the HLA-A3 recipients and/or recipients receiving an HLA-A3 graft, before becoming undetectable, at latest, at day 102 after transplantation. It is of major importance that transplantation monitoring laboratories bear in mind the possibility of therapeutic Ab detection when interpreting anti-HLA Ab results.

Recent studies have suggested that certain oncogenes, in particular members of the myc family, may be involved in the down-regulation of HLA class-I antigen expression observed in many types of tumor. We report that constitutive expression of an OK10 v-myc gene in human monoblastic U-937 cells results in a reduced expression of HLA class-I cell-surface expression and decreased levels of HLA class-I protein and mRNA. All class-I alleles, with the possible exception of HLA A3, were affected, as shown by one-dimensional isoelectric focusing (ID-IEF). Basal expression of the beta 2m chain was also reduced, although to a lesser extent. In addition, we show that the PMA-, and at least partially the IFN-alpha-induced increase in HLA class-I antigen expression, was inhibited in U-937-myc cells both at the protein and the mRNA level. In contrast, the response to IFN-gamma was normal. Another important difference in the response to IFN-gamma and alpha was that, while IFN-gamma abrogated the v-myc block of PMA-induced differentiation of U-937 cells, as previously reported, IFN-alpha did not. Our data show that v-myc negatively affects the regulation of both basal and inducible HLA class-I antigen expression.

HLA-A3 and HLA-B7 class-I genes are differentially regulated in human T lymphoma Jurkat cells, at the transcriptional level, the expression of the HLA-B7 gene being selectively increased following alpha, beta or gamma interferon (IFN) treatment. Using a series of hybrid CAT constructs, associating HLA-A3 and HLA-B7 complete or fragmented promoters, the differential regulation was shown to be associated with 2 nucleotide differences at positions -176 and -175 in the interferon regulatory sequence (IRS) of the HLA-A3 and the HLA-B7 genes. Replacement, using site-directed mutagenesis, of the 2 thymidine in the HLA-A3-IRS by adenine and cytidine found at the same positions in the HLA-B7-IRS was sufficient to restore IFN inducibility of the HLA-A3 promoter and efficient interaction with HeLa nuclear factors. Since the same nucleotide differences are shared by all sequenced HLA-A and HLA-B class-I genes, the differential induction by IFN of the transcription of the HLA-A3 and B7 genes might be a general locus-related property.

Human leukocyte antigen class I (HLA-I) molecules are highly polymorphic peptide receptors, which select and present endogenously derived peptide epitopes to CD8+ cytotoxic T cells (CTL). The specificity of the HLA-I system is an important component of the overall specificity of the CTL immune system. Unfortunately, the large and rapidly increasing number of known HLA-I molecules seriously complicates a comprehensive analysis of the specificities of the entire HLA-I system (as of June 2008, the international HLA registry holds >1,650 unique HLA-I protein entries). In an attempt to reduce this complexity, it has been suggested to cluster the different HLA-I molecules into “supertypes” of largely overlapping peptide-binding specificities. Obviously, the HLA supertype concept is only valuable if membership can be assigned with reasonable accuracy. The supertype assignment of HLA-A*3001, a common HLA haplotype in populations of African descent, has variously been assigned to the A1, A3, or A24 supertypes. Using a biochemical HLA-A*3001 binding assay, and a large panel of nonamer peptides and peptide libraries, we here demonstrate that the specificity of HLA-A*3001 most closely resembles that of the HLA-A3 supertype. We discuss approaches to supertype assignment and underscore the importance of experimental verification.

Hepatitis C virus (HCV) frequently causes chronic hepatitis, cirrhosis, and hepatocellular carcinoma after long-term persistent infection. Among various genotypes of HCV, HCV1b is resistant to standard interferon therapy, and thus the development of new treatment modality is needed.To provide a scientific basis for specific immunotherapy for HCV1b, we investigated HCV1b-derived epitope peptides recognized by human leukocyte antigen (HLA)-A11, -A31, or -A33-restricted cytotoxic T-lymphocytes (CTLs), and report here three novel vaccine candidate peptides selected by both antibody screening and CTL-inducing capacity from among 46 peptides of conserved regions of HCV1b sequences with binding motifs to HLA-A11, -A31, and -A33. Significant levels of IgG reactive to each of the three peptides were detected in the plasma of more than 50% of the HCV1b(+) patients. One peptide at positions 30-39 of the core protein induced peptide-specific CTLs from peripheral blood mononuclear cells (PBMCs) of HLA-A11(+), -A31(+), and -A33(+) patients. The other two peptides at positions 35-43 of the core protein and at positions 918-926 of the non-structural protein 2 also induced peptide-specific CTLs from the PBMCs of HLA-A11(+) and -A33(+) patients.Therefore, the peptide at positions 30-39 of the core protein could be an appropriate target molecule of specific immunotherapy for all HLA-A11(+), -A31(+), and -A33(+) patients with HCV1b-related diseases.

The underlying assumption in quantitative structure-activity relationship (QSAR) methodology is that related chemical structures exhibit related biological activities. We review here two QSAR methods in terms of their applicability for human MHC supermotif definition. Supermotifs are motifs that characterise binding to more than one allele. Supermotif definition is the initial in silico step of epitope-based vaccine design. The first QSAR method we review here--the additive method--is based on the assumption that the binding affinity of a peptide depends on contributions from both amino acids and the interactions between them. The second method is a 3D-QSAR method: comparative molecular similarity indices analysis (CoMSIA). Both methods were applied to 771 peptides binding to 9 HLA alleles. Five of the alleles (A*0201, A*0202, A*0203, A*0206 and A*6802) belong to the HLA-A2 superfamily and the other four (A*0301, A*1101, A*3101 and A*6801) to the HLA-A3 superfamily. For each superfamily, supermotifs defined by the two QSAR methods agree closely and are supported by many experimental data.

The recognition of MHC class I molecules by killer cell immunoglobulin-like receptors (KIR) is central to the control of NK cell function and can also modulate the CTL activation threshold. Among KIR receptors, KIR3DL2 is thought to interact with HLA-A3 and -A11, although direct evidence has been lacking. In this study, we show that HLA-A3 and -A11 tetramers specifically bind to KIR3DL2*001 transfectants and that this recognition is peptide-specific. Single amino acid substitutions in the nonamer peptide underline a critical role for residue 8 in recognition of KIR3DL2. However, the role of this interaction in vivo still remains to be established.

In order to analyze whether loci in the human leukocyte antigen (HLA) class I region may contribute to the HLA class II-associated genetic susceptibility to multiple sclerosis (MS), we examined selected microsatellite markers in 177 Nordic sib-pair families, 222 British sib-pair families, 323 sporadic Norwegian MS patients and 386 Norwegian controls. All samples were, in addition, genotyped for the HLA-DR DQ haplotype, and the Norwegian case-control samples were also typed for HLA-A and -B loci. In the Norwegian sporadic MS patients association was seen with HLA-A, HLA-B, and with the D6S265 marker, located 100 kb centromeric to HLA-A. Associations with HLA-A and D6S265 loci were also suggested when restricting the analysis to HLA-DR15 haplotypes. In the sib-pair data a similar trend was seen with marker D6S265. Higher genotypic relative risk (GRR) was found for individuals who carry both HLA-DR15 and -A3 (GRR = 15), compared to those who carry only HLA-DR15 (GRR = 7), only HLA-A3 (GRR = 3) or none of these alleles (GRR = 1). The highest risk was conferred by a combination of HLA-DR15 and -A3 (odds ratio (OR) = 5.2). These results suggest that HLA-A or a gene in linkage disequilibrium with it may contribute to the HLA class II-associated genetic susceptibility to MS.

Aim Implementation of the virtual crossmatch should aid redistribution of organs to sensitized individuals. However the number of organ offers falls rapidly with increasing cPRA. Thus, additional strategies to improve transplantation rate of highly sensitized individuals are warranted. A 49 year old Hispanic woman with ESRD from DMII/hypertension and no sensitizing events showed: HLA genotype A33 68, B7 51, Cw15 15, DR8 14 52, DQ4 7; cPRA of 100% by single antigen (SA) bead testing; and autoantibody to Cw15 and DR8,14,52. The patient was listed in UNOS with cPRA 100% on 7-21-10. Methods Additional flow crossmatching and HLA antibody testing to refine virtual crossmatch information in UNOS was performed to facilitate organ offers. Results SA results were reproducible over time and confirmed by the vendor laboratory, while testing using different reagents showed no antibody to HLA class II. The flow auto crossmatch and allo crossmatches against six surrogate donors with predictive DSA based on the SA findings (DR1,4,7,9,11,13,14,15,51,52,53) were negative. Using a MFI cutoff of 10,000 based on these results the patient’s cPRA was readjusted in UNOS to 4%. She was transplanted 7-30-13 with deceased-donor kidney (HLA A3 B35,61 C4,10 DR8,17, R52 DQ2,4). Delayed graft function requiring intermittent dialysis x5 occurred post-op. No increase in DSA by SA was noted post-transplant. She required readmission once with septic shock thought secondary to ischemic colitis. Creatinine eventually reached a nadir of 0.8 mg/dl. Conclusions This case illustrates variability in the performance of standard assays to evaluate the presence and clinical significance of DSA and the need to supplement these assays.

The MAGE gene family of tumour antigens are expressed in a wide variety of human cancers. We have identified 43 nonamer peptide sequences, from MAGE-1, -2 and -3 proteins that contain binding motifs for HLA-A3 MHC class I molecules. The T2 cell line, transfected with the cDNA for the HLA-A3 gene, was used in a MHC class I stabilisation assay performed at 37 degrees C and 26 degrees C. At 37 degrees C, 2 peptides were identified that stabilised HLA-A3 with high affinity (fluorescence ratio, FR1.5), 4 peptides with low affinity (FR 1.11-1.49) and 31 peptides that did not stabilise this HLA haplotype (FR1.1). At 26 degrees C, 12 peptides were identified that stabilised HLA-A3 with high affinity, 8 peptides with low affinity and 17 peptides that did not stabilise this HLA haplotype. Two peptides stabilised HLA-A3 at both temperatures. Small changes in one to three amino acids at positions distinct from the anchor residues altered peptide affinity. Data were compared to a similar study in which a peptide competition assay was used to investigate MAGE-1 peptide binding to several HLA haplotypes. This study demonstrates that anchor residues do not accurately predict peptide binding to specific HLA haplotypes, changes in one to three amino acids at positions distinct from anchor residues influence peptide binding and alternative methods of determining peptide binding yield different results. We are currently investigating the ability of these peptides to induce antitumour cytotoxic T lymphocyte activity as they may be of potential therapeutic value.

An HLA-A3-like supertype (minimally comprised of products from the HLA class I alleles A3, A11, A31, A*3301, and A*6801) has been defined on the basis of (a) structural similarities in the antigen-binding groove, (b) shared main anchor peptide-binding motifs, (c) the identification of peptides cross-reacting with most or all of these molecules, and (d) the definition of an A3-like supermotif that efficiently predicts highly cross-reactive peptides. Detailed secondary anchor maps for A3, A11, A31, A*3301, and A*6801 are also described. The biologic relevance of the A3-like supertype is indicated by the fact that high frequencies of the A3-like supertype alleles are conserved in all major ethnic groups. Because A3-like supertype alleles are found in most major HLA evolutionary lineages, possibly a reflection of common ancestry, the A3-like supermotif might in fact represent a primeval human HLA class I peptide-binding specificity. It is also possible that these phenomena might be related to optimal exploitation of the peptide specificity by human TAP molecules. The grouping of HLA alleles into supertypes on the basis of their overlapping peptide-binding repertoires represents an alternative to serologic or phylogenetic classification.

Studies of the major histocompatibility complex (MHC) in mouse indicate that the recombination sites are not randomly distributed and their occurrence is haplotype-dependent. No data concerning haplotype-specific recombination sites in human are available due to the low number of informative families. To investigate haplotype-specific recombination sites in human MHC, we here describe an approach based on identification of recombinant haplotypes derived from one conserved haplotype at the population level. The recombination sites were mapped by comparing polymorphic markers between the recombinant and assumed original haplotypes. We tested this approach on the extended haplotype HLA A3; B47; Bf*F; C4A*1; C4B*Q0; DR7, which is most suitable for this analysis. First, it carries a number of rare markers, and second, the haplotype, albeit rare in the general population, is frequent in patients with 21-hydroxylase (21OH) defect. We observed recombinants derived from this haplotype in patients with 21OH defect. All these haplotypes had the centromeric part (from Bf to DR) identical to the original haplotype, but they differed in HLA A and B. We therefore assumed that they underwent recombinations in the segment that separates the Bf and HLA B genes. Polymorphic markers indicated that all break points mapped to two segments near the TNF locus. This approach makes possible the mapping of preferential recombination sites in different haplotypes.

Background: An autoimmune cause and related immunological alterations resulting in recurrent spontaneous abortion (RSA) have been suggested in patients with unknown etiology. Materials and Methods: This study evaluated the autoantibody profile and other immunological parameters among RSA patients and normal pregnant women from Mumbai western India. Fifty RSA patients with unknown cause and greater than three consecutive abortions along with 50 normal pregnant women were studied for various auto antibodies such as ANA, anti-dsDNA, ANCA, AECA, 2 micro globulin, anti-HLA antibodies and ACLA using immunofluorescence microlymphocytotoxicity and ELISA. Immunological parameters such as HLA class I monoclonal antibody expression, CD3 (T cell), CD19 (B cell), and CD56 (NK cell) were estimated by flow cytometry. Results: The results revealed 34% positivity of all auto antibodies tested among patients. ANA(12%), ANCA (20%), AECA (24%), ACLA (8%), anti-dsDNA(0%), β2 microglobulin (14%), and anti-HLA antibodies(10%) among RSA patients were identified. An increased expression of HLA class I specific monoclonal antibody (10%) with HLA A3 (16%) specificity were found to correlate with shared HLA alleles among the RSA couples. Among normal pregnant (control) group ANA (2%), ANCA (2%), AECA (3%), ACLA (4%) and increased expression of CD56 with reduced HLA class I monoclonal were observed. Conclusion: Our findings suggest a possible role of various autoantibodies along with the related immunological parameters underlying RSA.Key words: Autoantibody, Human leukocyte antigen, India, Recurrent spontanous abortion

Thirteen unrelated patients with idiopathic haemochromatosis (eight men, five women) were studied. The diagnosis was based on clinical, biological, and histochemical findings. HLA typing was performed in all 13 and in all of their available first degree relatives (n = 31). HLA A3 was present in nine of 13 probands (69.2% compared with 18.8% in the group of 53 healthy blood donors and 22.4% in a selected Hungarian population (n = 1910). HLA B7 was present in five of 13 probands (38.4% compared with 11.3% and 14.6%). An A3B7 antigen association was found in five of 13 patients. The A3B7 haplotype was found in three, A2B12 and A2B38 haplotypes were found twice in 10 genotyped probands. Pedigree studies showed that there was one unaffected homozygote, 24 heterozygotes, and six non-carriers. Extended family and population studies are necessary to establish the prevalence of the gene in Hungary and an association with haplotypes other than A3B7.

HLA-A and HLA-B antigens were determined in 16 unrelated subjects orginating from Veneto affected by idiopathic haemochromatosis (IH). HLA-A3 was found in 13/16 patients vs. 300/1,348 controls (p less than 0.00005). Prevalences of A3,B35 haplotype were 0.4375 in patients vs. 0.0816 in controls (p less than 0.0005). Linkage disequilibrium analysis proved the existence of a positive third-order linkage disequilibrium among IH, HLA-A3 and HLA-B35 alleles. Our data confirm the close association of IH and HLA-A3 and prove the peculiar association of the disease with A3,B35 haplotype in north-eastern regions of Italy. The positive third-order linkage disequilibrium suggests a remote event (mutation, recombination or immigration) as origin for IH and A3,B35 association.

Familial lichen planus (FLP) was observed to have developed within a period of 3 years in 2 sisters as well as in the son of one of the women. In contrast to typical FLP, the eruption was generalized in only 1 of these patients; no atypical forms were observed; the response to topical treatment with steroids was rapid, and the relapses were few and mild. Previous reports of familial cases of lichen planus as well as the long interval between onset of the disease in the affected members of the family speak in favor of a genetic predisposition. HLA typing revealed HLA DR in all 3 patients. There was no increased incidence of HLA B7, HLA A3 or HLA A28.