Broad CD8+ T cell cross-recognition of distinct influenza A strains in humans.

Newly-emerged and vaccine-mismatched influenza A viruses (IAVs) result in a rapid global spread of the virus due to minimal antibody-mediated immunity. In that case, established CD8+ T-cells can reduce disease severity. However, as mutations occur sporadically within immunogenic IAV-derived T-cell peptides, understanding of T-cell receptor (TCRαß) cross-reactivity towards IAV variants is needed for a vaccine design. Here, we investigate TCRαß cross-strain recognition across IAV variants within two immunodominant human IAV-specific CD8+ T-cell epitopes, HLA-B*37:01-restricted NP338-346 (B37-NP338) and HLA-A*01:01-restricted NP44-52 (A1-NP44). We find high abundance of cross-reactive TCRαß clonotypes recognizing distinct IAV variants. Structures of the wild-type and variant peptides revealed preserved conformation of the bound peptides. Structures of a cross-reactive TCR-HLA-B37-NP338 complex suggest that the conserved conformation of the variants underpins TCR cross-reactivity. Overall, cross-reactive CD8+ T-cell responses, underpinned by conserved epitope structure, facilitates recognition of distinct IAV variants, thus CD8+ T-cell-targeted vaccines could provide protection across different IAV strains.

A novel HLA allele, HLA-B*37:06:02, identified in a Chinese family.

The novel allele HLA-B*37:06:02 differs from HLA-B*37:06:01 by a silent nucleotide substitution at codon 47P.

Identification of a novel allele, HLA-B*37:04:02, from a registered donor of the China Marrow Donor Program.

B*37:04:02 has 1 nt change from B*37:04:01 at nt 618 where G→A (codon 206 GCG→GCA) resulting in no coding change.

Description of two novel HLA-B alleles, B*37:34 and B*44:152.

Two novel HLA-B alleles were characterized. HLA-B*37:34 shows two nucleotide differences regarding B*37:10 at codons 79 (CGC>CGG) and 80 (ACC>ATC), resulting in one amino acid replacement at position 80 (T>I). HLA-B*44:152 differs from B*44:02:01 in one nucleotide at codon 81 (GCG>ACG) giving rise to a leucine to threonine substitution at position 81.

New insights into childhood Vernal keratoconjunctivitis-associated factors.

The purpose of this study was to test for detectable serum levels of antibodies usually associated with immune-related diseases in children with Vernal keratoconjunctivitis (VKC) and seek for their family history of allergies and autoimmune disorders. The association of human leukocyte antigens (HLA) with VKC was also investigated. We enrolled 181 VKC children and assessed total and specific IgE, antithyroglobulin (AbTG), antithyroidperoxidase (AbTPO), antitransglutaminase (tTG), and antinuclear antibodies (ANA) by standard procedures. Class I and II HLA typing was also carried out following standard protocols, and it was compared with that of healthy subjects. Patients were positive for AbTG (22%), AbTPO (14.6%), and ANA (15.8%), and AbTG positivity was associated with VKC severity (mean ocular score ± SD positive vs. negative: 6.56 ± 2.1 vs. 4.82 ± 2.1; p = 0.03). We found that 12.2% of VKC cases had a positive family history for psoriasis, 6.4% for other cases of VKC, and 5.2% for thyroiditis, while 50.2% of them were atopic. The expression of HLA class I B37 was significantly higher in VKC patients than in controls (7.1% vs. 2.1%, p = 0.04), although not confirmed after multiple antigens testing analysis. Our study suggests a role of common components associated with immune-based diseases in the clinical expression of VKC.

Haplotype-specific sequencing reveals a novel HLA-B*37 allele, B*3714.

We report on a novel human leukocyte antigen (HLA)-B allele, HLA-B*3714. This allele differs from HLA-B*3711 by two nucleic acid substitutions at positions 317 and 319 in exon 2, both resulting in amino acid exchanges. The first one leads to the exchange from arginine to leucine at position 82, and the latter one from glycine to arginine at position 83.

Juvenile Behçet's disease: highlighting neuropsychiatric manifestations and putative genetic mechanisms.

Behçet's disease is a multisystem inflammatory disorder of unknown etiology. We report a 12-year-old boy who presented with features of raised intracranial tension and seizures and was found to have cerebral venous sinus thrombosis on evaluation. Behçet's disease was diagnosed based on occurrence of recurrent oral and genital ulcers in the past and characteristic skin lesions subsequently. He also showed significant personality changes including multiple attempts of deliberate self-harm. Pedigree analysis revealed that six family members spanning three generations had recurrent oral ulcers and three members satisfied the criteria for Behçet's disease. Clinical features varied amongst the family members and there was suggestion of genetic anticipation. The index case was carrying HLA-B37/B7 and the mother was carrying B37/B40. Our report sheds light on the genetics of Behçet's disease. Unusual features were early age of onset, cerebral venous sinus thrombosis, significant personality changes and strong family history with phenotypic heterogeneity.

A MAGE-A4 peptide presented by HLA-B37 is recognized on human tumors by cytolytic T lymphocytes.

'Cancer-germline' genes such as those of the MAGE family are expressed in many tumors and in male germline cells, but are silent in normal tissues. They encode shared tumor-specific antigens, which have been used in therapeutic vaccination trials of cancer patients. MAGE-A4 is expressed in more than 50% of carcinomas of esophagus, head and neck, lung, and bladder. We report here the identification of a new MAGE-A4 encoded peptide, which is recognized by a cytolytic T lymphocyte (CTL) clone on HLA-B*3701. The sequence of the peptide is SESLKMIF. It corresponds to the MAGE-A4156-163 protein sequence. When tumor cells expressing MAGE-A4 were transfected with HLA-B*3701, they were recognized by the CTL clone, demonstrating that the peptide ought to be processed in tumor cells and could therefore serve as a target for therapeutic antitumoral vaccination.

Identification of a new HLA-B allele, B*3705 containing a Bw6 sequence motif.

HLA-B37, which is Bw4 type antigen frequently found in linkage disequilibrium with A1, Cw6 and DR10 in all ethnic groups, generally has a very low frequency all over the world. We report a new HLA-B*37 allele, B*3705, identified in two potential bone marrow donors in the Korean population. B*3705, which has the Bw6 nucleotide segment, differs from B*3701 in three nucleotide positions: 311, 317 and 319 in exon2. The serological profile of B*3705 did not exhibit the B37 specificity. The putative haplotype associated with B*3705 in the Korean population could be A*02-Cw*0602-DRB1*1001-DQA1*0101-DQB1*0501-DPB1*02011.

Complementary DNA sequence of the novel HLA-B*3704 allele.

The novel HLA-B*3704 allele was identified by polymerase chain reaction with sequence specific oligoneucletides (PCR-SSO) in a Spanish Caucasoid individual whose T-lymphocytes showed an ambiguous HLA-B phenotype. The nucleotide sequence of B*3704 was determined after reverse transcription-polymerase chain reaction (RT-PCR) amplification and molecular cloning of its complete coding region. B*3704 differs from B*3701 by a single nucleotide replacement that induces the substitution of histidine for tyrosine 171. Residue 171 is located in the alpha-helix of the alpha-2 domain, lining the A pocket of the peptide-binding site. Therefore, the His171 substitution seen in HLA-B*3704 is likely to affect its antigen-presenting properties and is probably responsible for the differentiated serological phenotype of this allele in comparison with B*3701.

A unique murine monoclonal antibody recognizing HLA-B53, B37, B51, B52, +/-B44.

Monoclonal antibodies have played an important role in studying the biochemistry of the HLA-Class I molecules. Some murine anti-HLA mAbs can identify configurations of HLA epitopes that have never been reported in human allosera. One of these configurations is identified by an IgM mAb designated as: BHA-1441. This antibody was produced using a lymphoblastoid cell line typed as: A*02, A*25; B*38, B*4402/4405; C*0501, C*07, BW4, as the immunogen. A lymphocytotoxicity test of this mAb over a panel of 109 frozen, 452 fresh and, later, 44 DNA typed T cells revealed its specificity as B53, 37, 51, 52, +/- 44. All of the antigens recognized by this mAb share the Bw4 motif at positions 81-83, except for the HLA-B37, which shares only 82L and 83R. Furthermore, while B37 and B44 cross-react due to the aspartic acid (D) substitution at position 156, the reactivity with B53, B5 (51,52), B37 and 60% of B44 cells, makes it unlikely that the target epitope could be due only to the primary amino-acid sequence. The antibody-binding site might involve changes in tertiary structure and peptides bound by the MHC. BHA-1441 is an interesting tool to study and type the HLA-B53 antigen and its cross-reactive epitopes.

HLA-association in patients with intolerance to mercury and other metals in dental materials.

A group of selected 25 patients with serious intolerance to heavy metals used for dental restoration were examined for HLA antigens. A significant increase for HLA -- B37, B47 and DR4 was found. The value of the relative risk is not significant after correction for the number of antigens tested and therefore further studies of more patients are needed.

Role of HLA-B and C alleles in development of psoriasis in patients from North India.

The association of HLA antigens with susceptibility for development of psoriasis vulgaris has been studied mostly using serologic methods. A number of different HLA class I antigens have been reported to be associated with predisposition to develop this disease. While Cw6 is the allele most commonly thought to confer risk for psoriasis, a number of HLA-B locus alleles have also been thought to be involved and, recently, in at least three studies, a specific amino acid in the HLA-C heavy chain has been implicated. With the recent development of molecular methods for typing for HLA class I alleles, it has become possible to re-examine this association by performing high resolution typing. In the present study we have investigated 38 psoriasis patients and 84 ethnically and geographically matched controls from North India. They were typed for HLA-B and HLA-C. The results showed the Cw*0602 was the main allele that was increased in this group of patients. The previously reported association with alanine-73 was not found to be significant. Cw*0602 was found in 71% of the patients. B*5701 and B*3701 were also increased but appeared to be secondary to linkage disequilibrium with Cw*0602.

Determinants of gingival overgrowth severity in organ transplant patients. An examination of the rôle of HLA phenotype.

The role of HLA phenotype as a risk factor for drug-induced gingival overgrowth was investigated in a cohort of 172 transplant recipients. Clinically significant overgrowth warranting surgical correction was observed in 72 patients (42%). Using stepwise regression modelling, 6 clinical parameters were identified as significant risk factors for the severity of gingival overgrowth. These were; age, sex, creatinine plasma level, duration of therapy, papilla bleeding index and concomitant medication with a calcium channel blocking drug. 3 HLA alleles were also identified as risk factors when adjusted for other clinically significant risk factors (HLA -DR2, A24, B37). However, when the p-values for the HLA variables were corrected to compensate for the use of multiple significance testing, only HLA-B37 remained statistically significant at the 5% level. Organ transplant patients are at risk of developing gingival overgrowth, with approximately 25% medicated with cyclosporin alone requiring corrective gingival surgery. This figure more than doubles in patients concomitantly medicated with a calcium blocking drug. The data at present available would suggest that the severity of gingival overgrowth is also significantly associated with the HLA-B37 phenotype.

HLA-B40, B18, B27, and B37 allele discrimination using group-specific amplification and SSCP method.

We developed a system for discriminating HLA-B40, B18, B27, and B37 alleles using a two-step PCR method followed by SSCP analysis. Fragments (0.8 kb) including exon 2, intron 2, and exon 3 were amplified in the first PCR. We used two sets of primers, one specific for HLA-B60-related alleles and the other specific for HLA-B61-related, B18, B27, and B37 alleles. No amplifications of other class I genes or pseudogenes were observed. In the second PCR, exon 2 and exon 3 were amplified separately, using diluents of the first PCR products as templates. HLA-B61-related, B18, B27, B37, and B60-related alleles were clearly discriminated in the SSCP analysis of the second PCR products. In a population study in which B61 alleles were analyzed, B*4003 was detected in two Japanese individuals in addition to two B61 alleles previously reported to occur in Japanese, B*4002 and B*4006. The relative frequencies of B*4002, B*4006, and B*4003 in Japanese were 58, 35, and 6%, respectively. The individuals having B*4003 are the first non-South Americans in whom this allele has been detected. The SSCP banding patterns of 18 HLA-B60-positive Japanese population samples were identical to those of a B*40012 sample for both exon 2 and exon 3. We also demonstrated that the B37 allele occurring in some Japanese is B*3701.

AIDS-associated Reiter's syndrome.

Classically, Reiter's syndrome was defined as a triad of arthritis, urethritis, and conjunctivitis. In 1981, the American Rheumatism Association revised its defining criteria for Reiter's syndrome as an episode of peripheral arthritis of more than 1 month's duration occurring in association with urethritis and/or cervicitis. Reiter's syndrome is also associated with mucocutaneous lesions. Reiter's syndrome was first described in association with the human immuno-deficiency virus (HIV) in 1987. The course of Reiter's syndrome in HIV is more severe, progressive, and refractory to treatment than in non-HIV-positive patients. The immunopathogenesis of Reiter's syndrome is linked to HLA-B27, which has been described as the disease susceptibility factor. The association of Reiter's syndrome and HLA-B27 positivity is 80%. Infectious agents may play a critical role in the initiation or perpetuation of Reiter's syndrome. It has been suggested that an amino acid sequence within the HLA-B27 molecule allows microbial peptides to bind and be presented to T cytotoxic cells (CD8), which results in a primary T cytotoxic cell response against various tissues. The role of the HIV in the pathogenesis of Reiter's syndrome is still being investigated. Human immunodeficiency virus may directly cause arthritis; it may increase the host's susceptibility to infection with arthritogenic organisms. Additionally, HIV infection increases the relative number of CD8 cells, which may play a key role in the pathogenesis of Reiter's syndrome. In this article, we present a case of Reiter's syndrome in an HLA-B27 and HIV-positive patient, and a review of the literature on the infectious, immunologic, and dermatologic aspects of Reiter's syndrome in HIV disease.

The peptide binding specificity of HLA class I molecules is largely allele-specific and non-overlapping.

To understand better the specificity of peptide binding by MHC class I molecules, we have evaluated the capacity of a panel of unrelated peptides to compete for the presentation of viral peptides presented by HLA-A3 and HLA-B27. The HIV-Nef7F peptide (74-82) was presented by HLA-A3 to Nef-specific HLA-A3-restricted CTL lines, and the influenza nucleoprotein peptide NP(380-393) was presented by HLA-B27 to NP(380-393)-specific HLA-B27-restricted CTL lines. In addition, we have extended studies from our group that have evaluated the capacity of a similar panel of peptides to inhibit presentation of an influenza nucleoprotein peptide NP (335-349) by HLA-B37 and a matrix peptide, M1 (57-68), by HLA-A2 to the appropriate peptide-specific CTL lines. Out of 41 peptides tested, only five bound to more than one of the MHC molecules analyzed. Pairwise comparisons of the peptide binding specificities among these four different class I molecules revealed no common competitor peptides in four of the six possible comparisons. Thus, each class I molecule appears to have a functionally distinct peptide binding site, as reflected by the ability to bind largely non-overlapping sets of peptides.

HLA-binding regions of HIV-1 proteins. I. Detection of seven HLA binding regions in the HIV-1 Nef protein.

The physical association of HLA class I or H-2 molecules with 36 HIV-1 Nef synthetic peptides was studied using a direct peptide binding assay (PBA) in solid phase. To assess the functional significance of the PBA results, the Nef peptides were also tested for their ability to inhibit the lytic activity of human or murine CTL. The PBA results showed that seven partly overlapping regions of the Nef protein contained MHC binding peptides (4-18, 46-67, 73-94, 100-128, 126-155, 182-198, and 192-206). Five of these seven regions included all the already described epitopes recognized by CD8+ human CTL. The two other regions, 4-18 and 46-67, are not yet described as antigenic for human CD8+ cells but they are located in the N-terminal part of Nef that was previously described as being stimulator for rat or chimpanzee CD4+ cells. Altogether, it can be concluded that 1) In virtually 100% of the cases, the PBA is capable to detect known antigenic peptides recognized by CTL. 2) The PBA and the functional inhibition assay provide similar results, supporting the functional significance of PBA results. 3) The PBA is easy to handle on a large scale, using multiple peptide and several MHC molecules, so that it can be used as a routine method for prevision of possibly epitopic sequences. 4) Systematic studies of peptides issued from the whole sequence of a given protein allow to map polyepitopic areas that are probably the most interesting parts of proteins for a vaccine purpose.