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H Inoko

Publications and source records attributed to H Inoko.

At least 307 records · Page 17Linked to original sources
PubMed1989

Differential susceptibility of HLA class II antigens induced by gamma-interferon in human neuroblastoma cell lines.

Five neuroblastoma cell lines have been examined for the induction of HLA class II antigens by a recombinant gamma-interferon. The expression of HLA-DR and -DP was induced on up to 80% of cells in two of five neuroblastoma cell lines examined (KP-N-SI and KP-N-RT). Low expression of HLA-DR and -DP was induced on the SK-N-DZ line in the presence of recombinant gamma-interferon for 10 days. In contrast HLA-DQ was not induced on any of five neuroblastoma cell lines studied. HLA-DR and -DP antigen induction was reversible, falling to nondetectable levels when interferon was removed from the culture medium. The reinduction of interferon to the culture medium again induced HLA-DR and -DP antigen expression in a fashion similar to that originally observed. These results were confirmed by Northern blot analysis using a probe to HLA-DR alpha mRNA. Recombinant interferon appears to induce HLA class II expression at the level of gene transcription or posttranscription. The results also indicate that HLA-DR, -DP, and -DQ antigens are independently regulated. Treatment of neuroblastoma cell lines with gamma-interferon results in the induction of a differentiated phenotype. Although the cytokine gamma-interferon induces neurofilament expression in some of the cell lines, this was not the case for all lines studied. Thus no correlation could be established between the morphological differentiation and either HLA class II or neurofilament expression. In addition, no correlation between response to recombinant interferon and N-myc amplification was noted. The biological significance of HLA class II expression on neuroblastoma cell lines by gamma-interferon may be related to the differentiation stage of neuroblastoma cells or may enable gamma-interferon-treated neuroblastoma cells to be recognized by cytotoxic T-cells.

Dose-Response Relationship, Drug↗
PubMed1989

Analysis of gene structure and antigen determinants of DR2 antigens using DR gene transfer into mouse L cells.

Three HLA class II DR beta genes and one DR alpha gene from the DR2 haplotype were cloned in cosmid vectors. The DR beta II gene might be a pseudogene lacking the first exon that encodes the leader peptide. The DR beta I and DR beta III genes were expressed, together with the DR alpha-chain, after transfection into mouse L cells. Restriction enzyme mapping of the DR beta genomic clones and reactivity of their products expressed on the L cell transfectant against mAb showed that the DR beta I and DR beta III genes encoded the nonpolymorphic and polymorphic DR beta chain, respectively. This arrangement is the reverse of that observed in other haplotypes, such as DR3, 4 and 6. The alignment of the HLA class II genes including the DR beta genes on the chromosome 6, however, was consistent with other haplotypes, e.g., centromere-DX beta-DX alpha-DV beta-DQ beta-DQ alpha-DR beta I-DR beta II- DR beta III-DR alpha-telomere. These results suggest that the susceptibility to mutations or gene conversions responsible for genetic polymorphisms depends on the gene itself and not on its location. Furthermore, absorption experiments of anti-DR2 allosera by the DR alpha/DR beta transfectants revealed that the so-called DR2 specificities were determined by multiple epitopes although both the DR beta I and DR beta III genes behaved similarly with DR2-specific antibodies.

Absorption↗
PubMed1989

Mapping and nucleotide sequence of a new HLA class II light chain gene, DQB3.

A genomic clone specifying a new HLA class II antigen beta chain, DQB3, was isolated from a human genomic phage library using a DQB1 cDNA probe under low stringency conditions. Southern hybridization and nucleotide sequence analyses identified the beta 2 domain exon (exon 3) with several deleterious mutations and the CP-TM-CY exon [connecting peptide, transmembrane, and cytoplasmic regions, (exon 4)], but the first, second, and fifth exons encoding the 5' UT-leader, the beta 1 domain, and the 3' UT domain of normal beta chains, respectively, were entirely missing. The nucleotide sequences of these two exons were distinct from those of other class II beta chain genes, but slightly more related to the DQB1 and DQB2 genes than to other class II genes. The DQB3 sequence mapped between DQA2 and DQB1, 15 kb upstream from DQA2, by analysis of overlapping cosmid clones. This mapping was supported by the fact that Taq I, Msp I, and Bam HI DQB3 polymorphisms were perfectly correlated with the DQA2 polymorphism and not with any polymorphisms in the DR or DQ subregion, suggesting the presence of a hot spot for recombination between DQB3 and DQB1.

Amino Acid Sequence↗
PubMed1989

No difference in the nucleotide sequence of the DQ beta beta 1 domain between narcoleptic and healthy individuals with DR2,Dw2.

Narcolepsy is a sleep disorder completely associated with HLA-DR2,Dw2. We demonstrated the 100% presence of three DQ beta fragments (EcoRI 2.4-kb, BamHI 2.9-kb, and PstI 12-kb) in narcoleptic patients that were detected in healthy DR2 controls only at decreased frequencies. In this paper, we have cloned the DQ beta gene from three Japanese narcoleptic patients and sequenced their beta 1 domain in order to study the sequence polymorphisms that might exist in the DQ beta genes of patients, but no difference in sequence could be found between narcoleptic and healthy individuals, suggesting that narcolepsy is not due to mutation in the DQ beta gene. In this context, a possible role of the HLA class II antigens in narcolepsy is discussed.

Base Sequence↗
PubMed1989

HLA-D typing of heterozygotes using restriction fragment length polymorphism in the HLA-DQ gene region on the basis of standard band patterns derived from HLA homozygotes.

Genomic DNAs from 37 Epstein-Barr virus-transformed HLA-D homozygous cell lines with different Dw specificities, Dw1-Dw23, and DKT2 were digested with four different restriction endonucleases (EcoRI, PstI, TaqI, and MspI) and hybridized to DQ alpha and DQ beta cDNA probes. Polymorphic patterns of multiple fragments correlating with Dw, DQ, and DR haplotypes were detected, and the restriction fragment length polymorphism standard pattern specific for each Dw, DQ, and DR specificity could be defined. The polymorphic fragment patterns of HLA-D heterozygotes were predicted simply by the summation of two standard patterns of HLA-D homozygotes and utilized to identify HLA-D specificities of 25 normal individuals, who are HLA heterozygotes in most cases. The HLA-D, -DR, and -DQ specificities defined by this DNA typing were compared with those assigned by serologic and cellular typing. There was good correlation, allowing the application of accurate genotyping by DQ alpha and DQ beta cDNA probes to HLA class II typing of HLA heterozygotes.

Base Sequence↗
PubMed1989

A simple and rapid method for HLA-DQA1 genotyping by digestion of PCR-amplified DNA with allele specific restriction endonucleases.

The second exon of the HLA-DQA1 genes was selectively amplified from genomic DNAs of 72 HLA-homozygous B cell lines by the polymerase chain reaction (PCR). Amplified DNAs were digested with HaeIII, Ddel, ScrFI, FokI and RsaI, which recognize allelic sequence variations in the polymorphic segments of the DQA1 second exon, and then subjected to electrophoresis in polyacrylamide gels. Eight different polymorphic patterns of restriction fragments were obtained, and seven were identical to patterns predicted from the known DNA sequences, correlating with each HLA-DQw type defined by serological typing. The remaining one pattern cannot be explained from the sequence data, suggesting the presence of a novel DQA1 allele at the nucleotide level. This PCR-RFLP method provides a simple and rapid technique for accurate definition of the HLA-DQ types at the nucleotide level, eliminating the need for radioisotope as well as allele specific oligonucleotide probes and can be extended and applied to HLA-DR, -Dw DP typing.

Alleles↗
PubMed1988

Cloning and analysis of HLA class I cDNA encoding a new HLA-C specificity Cx52.

HLA-C loci frequently have an unclassifiable "blank (CwBL)" specificity. It is unclear whether HLA-C specificities associated with the haplotypes of A24 Bw52 CwBL DR2 DQw1 and Aw33 B44 CwBL DRw13 DQw1 in Japanese (tentatively named Cx52 and Cx44, respectively) really exist. Southern hybridization experiments revealed that restriction enzyme-cleaved genomic DNA from AKIBA, consanguineous HLA homozygote, two other homozygotes with the former haplotype, and three homozygous cells with the latter haplotype hybridized strongly with an HLA-C-specific probe. We have screened the cDNA library constructed from AKIBA to isolate cDNA clones encoding the putative Cx52 antigen, and picked up 103 cDNA clones with HLA-class I DNA probes as possible candidates. By restriction enzyme mapping and Southern hybridization of selected clones, we identified three isotypes of cDNA clones, pA01, pB55, and pC68, which appeared to encode A24, Bw52, and Cx52, respectively. The nucleotide sequence of pC68 showed higher homology with exons of the HLA-C gene than with those of the HLA-A and HLA-B genes, especially in exons 6-8 which include the HLA-C-specific region. Comparison of amino acid sequences showed more than 86% homology among Cw1, Cw2, Cw3, and new pC68-encoded Cx52 proteins. These results support the notion that the inability to define C antigens serologically in this Cx52 haplotype is not due to a HLA-C gene deletion or mutation, but to the absence of typing sera.

Amino Acid Sequence↗
PubMed1988

Taq I-generated HLA-DQ alpha polymorphism in Japanese patients with narcolepsy.

Taq I-generated HLA-DQ alpha restriction fragment length polymorphism was examined in Japanese patients with narcolepsy. All patients were DR2 positive and shared a 6.0 kb fragment, although this fragment was found only in 54% of the healthy DR2-positive Japanese. This finding added the DQ alpha gene to the list of candidates for the possible narcolepsy-susceptibility gene. In contrast, there was no complete association between narcolepsy and DX alpha restriction fragment length polymorphism. These findings suggest that a narcolepsy-susceptibility gene is located closer to the DQ locus than to the DX locus.

Chromosomes, Human, Pair 6↗
PubMed1988

Mode of antigen presentation required for triggering of T cell response: analysis by use of azobenzenearsonate-tyrosine derivatives as antigens and L cells transfected with I-Ak genes as antigen presenting cells.

Our previous study demonstrated (1) that the presence of charged groups (amino and carboxyl groups) at the alpha-carbon of tyrosine is essential for activation of azobenzenearsonate-L-tryosine (ABA-L-Tyr specific T cells, and (2) that T cells recognizes ABA-L-Tyr in association with macromolecules on syngeneic spleen cells used as antigen presenting cells (APC). The present study was undertaken to confirm that the macromolecules on APC are Ia molecules, by using L cells transfected with A beta k and A alpha k genes as APC. I-Ak restricted ABA-L-Tyr specific cloned T cells, and T hybridoma cells were activated by ABA-L-Tyr in the presence of the L cell transfectants, of which expression of I-Ak molecules had been proven by specific binding of anti-I-Ak monoclonal antibody (MAb) 10.2.16 on the cell surface. The pattern of responses of I-Ak restricted ABA-L-Tyr specific T cells to various ABA-Tyr derivatives presented by the I-Ak expressing L cell transfectants was similar to the pattern obtained by using H-2k spleen cells as APC. Thus, ABA-L-Tyr and ABA-Tyr derivatives, which have both amino and carboxyl groups at the alpha-carbon of Tyr, presented by the L cell transfectants triggered good response of I-Ak restricted ABA-L-Tyr specific T cells. By contrast, ABA-Tyr derivatives, which lack the amino or carboxyl group, or both groups, at the alpha-carbon of Tyr, presented by the L cell transfectants could not activate the ABA-L-Tyr specific T cells at all. Furthermore, anti-I-Ak MAb, but not anti-I-Ek MAb, inhibited completely the response of I-Ak restricted ABA-L-Tyr specific T cells to ABA-L-Tyr presented by the L cell transfectants. These results indicate strongly that the macromolecules on APC which associate with ABA-L-Tyr are A beta k A alpha k gene products, i.e., I-Ak molecules.

Animals↗
PubMed1988

HLA-DP typing by analysis of DNA restriction fragment length polymorphisms in the HLA-DP beta subregion.

HLA class II antigens are encoded in the HLA-D region and are highly polymorphic. Southern hybridization technique was used to analyze restriction fragment length polymorphisms (RFLPs) in the DP beta gene and an attempt was made to correlate these with DP haplotypes derived from primed lymphocyte typing (PLT) analysis. Digestion of DNA from 32 Epstein-Barr virus (EBV)-transformed cell lines (of haplotypes DPw2, DPw3, DPw4, DPw5, and Cp63) with three different restriction endonucleases. Southern transfer, and hybridization to the DP beta cDNA probe revealed multiple fragments in all cell lines tested. The polymorphic patterns of these fragments were found to correlate with DP haplotypes, suggesting the possibility that the analysis of DNA RFLPs (DNA typing) in the HLA-DP beta subregion can distinguish and identify HLA-DP haplotypes.

DNA↗
PubMed1988

Specific restriction fragment length polymorphism on the HLA-C region and susceptibility to psoriasis vulgaris.

In psoriasis vulgaris, the HLA class I Cw6 specificity has previously been recognized as the most commonly associated antigen serologically. This study was carried out to investigate whether or not the gene controlling the susceptibility to psoriasis vulgaris existed on the HLA, especially the HLA-C region. At first, we analyzed the restriction fragment length polymorphism (RFLP) of 13 patients with psoriasis vulgaris and 6 healthy controls who were all positive for at least one allele of HLA-Cw6. To characterize RFLP in psoriasis patients who did not have HLA-Cw6, 12 patients and 10 healthy controls who had HLA-Cw7 were also examined. Southern hybridization of genomic DNA demonstrated that DNA polymorphisms of the HLA-C antigen gene could not be found in any psoriasis vulgaris patient whether HLA-Cw6 or Cw7. However, a 4.5 kb BamHI fragment and a 3.1 kb PstI fragment were lacking in some healthy controls who had either HLA-Cw6 or Cw7. This study suggests that the presence of RFLP in the HLA-C gene is associated with psoriasis vulgaris. These specific fragments may help predispose individuals to psoriasis vulgaris, or may be essential for the development of the disease.

DNA↗
PubMed1988

[Structure and function of human transplantation antigens].

Human transplantation antigens encoded in the major histocompatibility complex (MHC) region play a key role in regulating the immune responses. Here, we will describe the summary of our analyses on the structure and function of the human MHC molecules, HLA antigens as follows. 1) The genomic organization of the HLA antigen region was examined by cosmid cloning and pulsed-field gel electrophoresis technique. The HLA antigen region spans over at least 3,000 kb, and constitutes a multigene family. 2) Genetic polymorphisms in the HLA gene region were analyzed by Southern hybridization with restriction endonuclease digested genomic DNA using the class II cDNAs as probes (RFLP) and found to be tightly associated with each allo specificity. 3) The functional expression of the HLA class II gene product were observed after transfer of their cloned genes into the mouse fibroblast and human lymphocytes. 4) Narcolepsy is completely associated with HLA-DR2 Dw2, but no difference in the sequence of the DQ beta 1 domain could be found between narcoleptic and healthy individuals. This fact suggests that narcolepsy is not caused by mutation in the DQ beta gene. Based on results, it was inferred that one or both of the two Asps within the second variable region in the first domain of the DR beta chain is directly correlated with predisposition to narcolepsy.

Amino Acid Sequence↗
PubMed1987

Linkage of TNF genes to the HLA-B locus.

Pulsed field gel electrophoresis was used to determine the location of the tumour necrosis factor (TNF) alpha and beta genes. They were shown to be linked to the HLA-B locus; analogous to their location in mouse, between the complement (class III) region and H-2D. However, the distance between the TNF genes and the class I region was much greater in man, namely about 260 kb, compared to 70 kb in the mouse. This finding may have implications for some HLA associated diseases.

Genes↗