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H Inoko

Publications and source records attributed to H Inoko.

At least 181 records · Page 10Linked to original sources
PubMed1996

HLA-C genotyping of patient with Behçet's disease in the Japanese population.

Behçet's disease has been known to be strongly associated with a particular HLA-B allele, B51. To address the possibility that the HLA-C gene, which is closely linked to HLA-B but has been poorly defined for allo-antigen specificity by the serologic method is involved in the susceptibility to Behçet's disease, HLA-C genotyping was performed for 90 Japanese Behçet's disease patients by the PCR-SSP method. The frequencies of HLA-Cw*14 and -Cw*15 were significantly higher in the patient with Behçet's disease as compared to the controls (48.9% vs. 24.0%, p = 0.0005, and 17.8% vs. 7.3%, p = 0.0434, respectively). On the other hand, the frequencies of HLA-Cw*0304 and -Cw*01 were significantly decreased in the patient group as compared to the control group (7.8% vs. 25.0%, p = 0.0027, and 23.3% vs. 37.5%, p = 0.0398, respectively). The significantly higher HLA-Cw*14 and -Cw*15 alleles may tightly correlate with the B51 antigen, and hence may have increased as a result of a linkage disequilibrium with B51. Accordingly, the HLA-C allele frequencies were compared for the B51-positive or -negative patients and controls, but there was no HLA-C allele showing a significant difference between these patient and control groups. Conversely, analysis of the HLA-B allelic distribution in association with HLA-Cw*14 revealed that in the healthy controls, B44 and B51 were present at the frequencies of 57.1% and 35.7% of the HLC-Cw*14-positive individuals, respectively. In contrast, in the Cw*14-positive patients the frequency of B44 was merely 14.0% (p = 0.0001) and that of B51 was significantly high, amounting to 82.0% (p = 0.0001). These facts suggest that the pathogenic gene of Behçet's disease is not the HLA-C gene (HLA-Cw*14 and/or HLA-Cw*15) but the HLA-B gene (HLA-B51) itself or a non-HLA gene residing in the centromeric side of the HLA-B gene rather than in the telomeric side around the HLA-C gene. This finding supports our previous mapping result, which located the susceptible gene between the TNF and HLA-B genes.

Alleles↗
PubMed1996

Human leukocyte antigen-DRB1*1502 (DR2Dw12) transgene reduces incidence and severity of arthritis in mice.

A strong correlation exists between susceptibility to RA in humans and some DRB1 alleles of the MHC region, such as DRB1*0401 and DRB1*0101. Meanwhile, incidences of other DR specificities, such as DR2, DR5, or DR7 have often been found reduced among RA patients. Like RA, susceptibility to mouse CIA is influenced by the MHC class II loci. To analyze the effect of a DRB1 molecule associated with low incidence of RA on mouse CIA, a human DRB1*1502 (DR2Dw12) transgene was introduced into CIA-susceptible B10.RQB3 (H2Aq) mice. Transgene-positive DRB1*1502 mice showed a significant reduction in the incidence and severity of arthritis. Moreover, the clinical reduction of arthritis correlated with the T-cell proliferative response of B10.RQB3-DRB1*1502 mice against a self-derived DRB1 peptide from the third hypervariable region. Our results suggest that the DRB1*1502-mediated protection against CIA can be explained by the DRB1 molecule acting as a source of self-antigenic peptide which interferes with the T-cell response against immunodominant regions(s) of the arthritogenic type II collagen molecule. By analogy, a similar mechanism might play a critical role in influencing the class II-associated predisposition to RA.

Animals↗
PubMed1996

Analysis of HLA-DM polymorphisms in sarcoidosis.

Sarcoidosis is a multisystemic granulomatous disorder showing significant increases in the HLA-DRB1*11, *12, *14 and *08 alleles in the Japanese population. To evaluate the role of polymorphism in the DMA and DMB genes in predisposition to sarcoidosis, seventy Japanese patients with sarcoidosis and 95 unrelated healthy controls were analyzed in the third exon polymorphisms within the DMA and DMB genes by the PCR-RFLP method. There were no differences in the distribution of DMA alleles between the patient and control groups. The frequency of DMB*0102 was higher (p < 0.05) and that of DMB*0101 was lower (p < 0.05) in the patients than in the healthy controls. However, this association and negative association could be explained by linkage disequilibrium with the disease-associated DRB1 alleles. The DMA and DMB genes do not primarily confer the susceptibility to sarcoidosis.

Adult↗
PubMed1996

Chromosomal localization of the proteasome Z subunit gene reveals an ancient chromosomal duplication involving the major histocompatibility complex.

Proteasomes are the multi-subunit protease thought to play a key role in the generation of peptides presented by major histocompatibility complex (MHC) class I molecules. When cells are stimulated with interferon gamma, two MHC-encoded subunits, low molecular mass polypeptide (LMP) 2 and LMP7, and the MECL1 subunit encoded outside the MHC are incorporated into the proteasomal complex, presumably by displacing the housekeeping subunits designated Y, X, and Z, respectively. These changes in the subunit composition appear to facilitate class I-mediated antigen presentation, presumably by altering the cleavage specificities of the proteasome. Here we show that the mouse gene encoding the Z subunit (Psmb7) maps to the paracentromeric region of chromosome 2. Inspection of the mouse loci adjacent to the Psmb7 locus provides evidence that the paracentromeric region of chromosome 2 and the MHC region on chromosome 17 most likely arose as a result of a duplication that took place at an early stage of vertebrate evolution. The traces of this duplication are also evident in the homologous human chromosome regions (6p21.3 and 9q33-q34). These observations have implications in understanding the genomic organization of the present-day MHC and offer insights into the origin of the MHC.

Amino Acid Sequence↗
PubMed1996

cDNA cloning of the human homologues of the mouse Ke4 and Ke6 genes at the centromeric end of the human MHC region.

cDNA clones corresponding to the HKE4 and HKE6 genes at the centromeric end of the HLA region on human chromosome 6p21.3 were isolated and characterized. The predicted amino acid sequences of HKE4 and HKE6 exhibited 81.5 and 85.6% identity to the mouse homologues, Ke4 and Ke6, respectively. HKE4 may encode a membrane protein with histidine-rich charge clusters. HKE6 possesses remarkable amino acid sequence conservation with several bacterial proteins with oxidoreductase function and also shows significant homology with the two unique functional domains containing the nucleotide cofactor binding site and the consensus motif characteristic of the members of the superfamily of short-chain alcohol dehydrogenases such as human and rat steroid and prostaglandin dehydrogenases.

Amino Acid Sequence↗
PubMed1996

Isolation of cDNA and genomic clones of a human Ras-related GTP-binding protein gene and its chromosomal localization to the long arm of chromosome 7, 7q36.

A Ras-related GTP-binding protein cDNA has been isolated from a human skin fibroblast cDNA library using a genomic subclone derived from a YAC clone as a probe. The polypeptide, consisting of 184 amino acids deduced from nucleotide sequences, contains five repeats of the Ras-related GTP-binding region and is highly homologous to the rat RHEB (Ras homologue enriched in brain) gene, which encodes a Ras-related growth factor- and synaptic activity-regulated protein, with 98.9% amino acid identity. Therefore, it is suggested to be a human homologue of the rat RHEB protein, and we have designated it human RHEB. Using fluorescence in situ hybridization, we concluded that this human RHEB gene was localized to band q36 on chromosome 7. Considering the chromosomal localization as well as the potential function of this protein, it will be very important to investigate whether it may play a role in the etiopathogenesis of holoprosencephaly type 3 or hereditary sacral agenesis, in which the disease susceptible locus is linked to the microsatellite marker, D7S22, in this chromosomal region, 7q36.

Amino Acid Sequence↗
PubMed1996

The coexistence of systemic sclerosis and rheumatoid arthritis in five patients. Clinical and immunogenetic features suggest a distinct entity.

To elucidate the clinical characteristics and pathogenesis of scleroderma-rheumatoid arthritis (SSc-RA) overlap syndrome, we analyzed the clinical features of 5 patients with SSc-RA overlap. Their HLA phenotypes and genotypes were also determined. Generalized skin sclerosis, severe seropositive polyarthritis, pulmonary fibrosis, anti-topoisomerase I antibodies, and HLA-DR4,53;DQA1*0301;DBQ1*04 haplotype were observed in all of the patients. Similar clinical features were recognized in most of the 10 cases reported previously. Our case studies indicate that SSc-RA overlap may be a distinct entity.

Aged↗
PubMed1996

Clinical correlations with HLA type in Japanese patients with connective tissue disease and anti-U1 small nuclear RNP antibodies.

OBJECTIVE: To elucidate the roles of HLA genes in the clinical presentation of patients with connective tissue disease and serum anti-U1 small nuclear RNP antibody. METHODS: HLA class I antigens and HLA class II alleles were determined in 43 Japanese patients with anti-U1 RNP antibody alone, by microcytotoxicity testing and DNA typing, respectively. Prospectively recorded clinical and laboratory features were analyzed in relation to HLA class I and class II types. RESULTS: DQB1*0303 was associated with lupus-related symptoms including fever, malar rash, oral ulcers, hypocomplementemia, and high-titer anti-double-stranded DNA antibody. Other HLA-clinical associations included DR2 with pleuritis, DR4 with hand swelling, and DRB1*0405 with arthritis. CONCLUSION: These HLA-clinical associations explain, in part, the heterogeneous clinical presentation in patients with anti-U1 RNP antibody.

Adolescent↗
PubMed1996

Development and characterization of a novel monoclonal antibody (mNI-11) that induces cell adhesion of the LPS-stimulated human monocyte-like cell line U937.

A monoclonal immunoglobulin G1 (IgG1) antibody (mAb), designated mNI-11, was produced by immunizing mice with the lipopolysaccharide (LPS)-stimulated monocyte-like cell line U937. The reactivity of mNI-11 was tested by the indirect immunofluorescence method. The antigen defined by mNI-11 was found to be expressed on U937 cells, LPS-stimulated U937 cells, normal CD14+ cells (monocytes/macrophages), and human umbilical vein endothelial cells (HUVECs). Expression of the antigen defined by mNI-11 on HUVECs slightly increased in response to exposure to tumor necrosis factor-alpha (TNF-alpha) and phorbol myristate acetate (PMA). When the reactivity of mNI-11 and mAbs binding human differentiation antigens such as CD11a, CD11b, CD11c, CD14, CD16, CD18, CD23, CD28, CD29, CD31, CD43, CD44, CD45RA, CD49d, CD50, CD54, CD58, CD80, CD102, CD106, HLA-class I, or HLA-class II antigen was compared, no mNI-11 reactivity resembling that of these mAbs was found. mNI-11 markedly induced homotypic cell aggregation of U937 cells when they were stimulated with LPS. The mNI-11-induced aggregation of LPS-stimulated U937 cells, referred to as LPS-U937 cells, required neither Fc receptor engagement nor cross-linking of the antigen defined by mNI-11 because aggregation was induced by both F(ab')2 fragments and monovalent F(ab') fragments of mNI-11. The mNI-11-induced aggregation was blocked by the addition of ethylenediaminetetraacetate, and also when incubated at 4 degrees C. mAbs to CD11a/CD18 (lymphocyte-function associated antigen-1; LFA-1) and CD54 (intercellular adhesion molecule-1; ICAM-1) completely blocked the LPS-U937 cell aggregation induced by mNI-11. The LPS-U937 cell aggregation induced by mNI-11 was partially but not completely blocked by the protein kinase C inhibitors sphingosine and H-7, and was completely blocked by the protein-tyrosine kinase inhibitor genistein. Interestingly, mNI-11 markedly promoted LPS-U937 cell adhesion to HUVECs. The mNI-11-induced LPS-U937 cell adhesion to HUVECs was not reduced in the presence of LFA-1 (CD11a/CD18) or ICAM-1 (CD54) mAbs. On the other hand, LPS-U937 cells, whether treated with mNI-11 or not, sufficiently adhered to the extracellular matrix protein fibronectin, but not to laminin or collagen type I. However, mNI-11 did not markedly promote LPS-U937 cell adhesion to fibronectin. Adhesion of LPS-U937 cells treated with mNI-11 to fibronectin was completely blocked by CD29 (beta chain of very late antigens) mAb. The surface antigen recognized by mNI-11 had a molecular size of approximately 97 kDa under non-reducing conditions and approximately 117 kDa under reducing conditions, as determined by immunoblotting analysis. We found that mNI-11 recognizes an adhesion-associated molecule distinct from any previously reported in terms of its pattern of cellular distribution and molecular weight, and also found that mNI-11 has activity which induces cell adhesion/aggregation of U937 cells when stimulated with LPS.

Amino Acid Sequence↗
PubMed1996

Allelic repertoire of the human MHC class I MICA gene.

The hallmark of the classical major histocompatibility complex (MHC) class I molecules is their astonishing level of polymorphism, a characteristic not shared by the nonclassical MHC class I genes. A distinct family of MHC class I genes has been recently identified within the human MHC class I region. The MICA (MHC class I chain-related A) gene in this family is a highly divergent member of the MHC class I family and has a unique pattern of tissue expression. We have sequenced exons encoding the extracellular alpha1, alpha2, and alpha3 domains of the MICA gene from twenty HLA homozygous typing cell lines and four unrelated individuals. We report the identification of eleven new alleles defined by a total of twenty-two amino acid substitutions. Thus, the total number of MICA alleles is sixteen. Interestingly, a tentative superimposition of MICA variable residues on the HLA-A2 structure reveals a unique pattern of distribution, concentrated primarily on the outer edge of the MICA putative antigen binding cleft, apparently bordering an invariant ligand binding site.

Alleles↗
PubMed1996

Cloning, sequencing, and chromosomal localization of two tandemly arranged human pseudogenes for the proliferating cell nuclear antigen (PCNA).

We have characterized a human genomic clone carrying two pseudogenes for the proliferating cell nuclear antigen (PCNA), which were tandemly arranged on human Chromosome (Chr) 4. One is a processed pseudogene that showed a 73% nucleotide homology to the human PCNA cDNA and possessed none of the introns existing in the functional PCNA gene. This pseudogene presumably arose by reverse transcription of a PCNA mRNA followed by integration of the cDNA into the genome. The other is a 5' and 3' truncated pseudogene that showed a nucleotide homology to a 3' region of the exon 4 and to a 5' region of the exon 5 of the PCNA gene and did not have the intronic sequence between the exons 4 and 5. Both pseudogenes had the same nucleotide deletion as compared with the human functional PCNA gene. A phylogenetic analysis of PCNA gene family, including the functional PCNA gene and another PCNA pseudogene located on a different chromosome, revealed that the truncated pseudogene exhibits the closest evolutionary relationship with the processed pseudogene, suggesting that the truncated pseudogene was generated by duplication of the processed pseudogene after translocation to Chr 4. Furthermore, fluorescence in situ hybridization revealed that these pseudogenes are located on the long arm of Chr 4, 4q24.

Animals↗
PubMed1996

Genetic polymorphisms of the major histocompatibility complex-encoded antigen-processing genes TAP and LMP in sarcoidosis.

Sarcoidosis is a granulomatous disease showing a significant increase in the HLA-DR5, -DR6, and -DR8 associated alleles in Japanese. To investigate whether the class I antigen-processing genes, encoded within the MHC class II region between the HLA-DP and -DQ loci, are involved in determining the susceptibility to sarcoidosis, TAP1, TAP2, and LMP2 alleles were analyzed by the PCR-RFLP method in 85 Japanese patients with sarcoidosis and 91 healthy controls. There were no significant differences in the distribution of TAP1 and LMP2 alleles between the subgroups of the patients and controls positive or negative for DR5, DR6, and DR8. A significant decrease in the frequency of TAP2*0201 was found among the patients negative for DR5, DR6, and DR8 as compared to the DR-matched controls (p < 0.05), but this could be explained by its linkage disequilibrium to the negatively associated allele DR1. These findings suggest that the TAP or LMP2 gene is not primarily involved in the susceptibility to sarcoidosis. In the course of this study, a linkage disequilibrium was observed in the Japanese population between TAP1 and TAP2 alleles, TAP1*0201 and TAP2*0102.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1996

LMP7 polymorphism in Japanese patients with sarcoidosis and Behçet's disease.

To evaluate the influence of the MHC-linked LMP7 gene on disease susceptibility in HLA class I and class II-associated diseases, the distribution of LMP7 alleles was determined using the PCR-RFLP method in 69 Japanese patients with Behçet's disease, 65 patients with sarcoidosis, and 100 unrelated healthy controls. No differences were found between either of the patient groups and the healthy control group, indicating that LMP7 allelic variation may not contribute to the pathogenesis of either Behçet's disease or sarcoidosis. We also analyzed linkage disequilibria between LMP7 and HLA class II alleles in Japanese populations.

Alleles↗
PubMed1996

Human pseudoautosomal boundary-like sequences: expression and involvement in evolutionary formation of the present-day pseudoautosomal boundary of human sex chromosomes.

The human genome is composed of long-range mosaic structures of G+C% (GC%), which are thought to be related to chromosome bands. We previously identified a boundary of Mb-level domains of GC% mosaic structures in the human major histocompatibility complex (MHC) and found in the domain boundary a sequence very similar to pseudoautosomal boundary (PAB) sequences of human sex chromosomes. We designated it 'PABL' and found many PABLs in the human genome. By analysis of six genomic and six transcribed PABLs, a core and consensus sequence of about 650 nt was defined; the 3'- and 5'-edges of the PABLs were strictly conserved. Northern blot analysis showed sizes of PABL transcripts to be 5-10 kb in length. Divergence time of PABLs was estimated to be 60-120 million years ago by analysis of human PABLs and PABXY1 of seven primates, and the evolutionary rates deduced showed PABLs to have been under selective constraints. A model for evolutionary formation of the present pseudoautosomal boundary was proposed by postulation of illegitimate recombination between two PABLs.

Animals↗
PubMed1996

HLA class I antigens in Japanese patients with melanoma.

In this study, we analyzed the frequencies of human leukocyte antigen (HLA) class I alleles in 110 Japanese patients with melanoma using serological methods, and compared such frequencies with clinical parameters. As expected, frequencies of HLA allele distribution in patients with melanoma reflected the frequencies observed in the normal Japanese population. Because these are different from populations belonging to other races (e.g., white), it followed that the HLA allele distribution in melanoma patients varies among different races. This differences may have significant implications for T-cell-mediated, HLA-restricted therapeutic modalities. No significant associations between HLA and clinical parameters were noted in this study. This report may help design future clinical trials involving therapeutic approaches based on HLA-restricted mechanisms.

Adult↗