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Biomedical subjects

T Juji

Publications and source records attributed to T Juji.

At least 253 records · Page 14Linked to original sources
PubMed1990

HLA antigens in Japanese patients with myasthenia gravis.

HLA antigens in 104 Japanese patients and 41 families with myasthenia gravis (MG) were investigated. The frequencies of DR9 and DRw13 were significantly increased in the patients who developed MG before 3 yr of age. The DQw3 antigen was positive for all the patients that developed MG before 15 yr with only one exception. All the examined cases that developed MG before 3 yr (including this DQw3 negative patient) had the same DQA and DQB DNA restriction fragments. These HLA frequencies decreased as the age of onset increased, and no significant association was observed in adult-onset MG. No patients had B8, DR3, and DQw2. The relative risk was higher for the DR9/DRw13 heterozygotes (37.4) than for DR9 (16.4) or DRw13 (7.1) in the childhood-onset MG. Statistical analysis suggested that DR9 and DRw13 (or DQw1 and DQw3) act synergistically in the disease development. Family study revealed diverse DR9 haplotypes. The most frequent DRw13 haplotype was Bw44-BFF-C4A3B1-DRw13-DQw1, which may be evolutionarily related to the caucasian B8-DR3-DQw2 haplotype. These results showed that MG in early childhood in Japanese individuals is genetically different from that in adulthood and that in caucasians.

Age Factors↗
PubMed1990

HLA-D region genomic polymorphism associated with Takayasu's arteritis.

Takayasu's arteritis, with a strong predilection for women and particular geographic areas, has revealed significant association with human lymphocyte antigens (HLA) specificities. In the present study, the authors investigated for the first time the association of Takayasu's arteritis and HLA at the genomic level. By use of a restriction endonuclease Taq-I and a DQA cDNA probe, HLA-D region restriction fragment length polymorphism was examined in 32 Japanese patients. It was revealed that 65.6% of the patients shared a 6.6 kb fragment, although this fragment was found in 35.3% of the healthy Japanese (Chi square: 6.07, p less than 0.02). This finding suggest that HLA-D region gene variations determine susceptibility to Takayasu's arteritis.

Adult↗
PubMed1990

High frequency of aspartic acid at position 57 of HLA-DQ beta-chain in Japanese IDDM patients and nondiabetic subjects.

The HLA-DQ beta-chain (DQB1) genes of 72 Japanese patients with insulin-dependent diabetes mellitus (IDDM) and 85 control subjects were studied with polymerase chain-reaction (PCR) amplification and allele-specific oligonucleotide hybridization. DQW4 (DQBBlank) and DQw9 (DQB3.3) were increased in IDDM patients compared with the control subjects, and DQB1.2, DQB1.9, and DQw7 (DQB3.1) were decreased. Thirty-five (48.6%) IDDM patients had both alleles carrying an aspartic acid at position 57 of the DQ beta-chain (Asp 57), 35 (48.6%) were Asp 57/non-Asp 57 heterozygous, and 2 (2.8%) had non-Asp 57 alleles only. Of 85 control subjects, the respective values for these three genotypes were 49 (57.6%), 29 (34.1%), and 7 (8.2%), respectively. The high frequency of Asp 57 alleles in both IDDM and control subjects contrasts with data for Whites. Therefore, the Asp 57 hypothesis that the presence of an aspartic acid at position 57 of DQ beta-chain provides protection against developing IDDM is not tenable for Japanese IDDM patients. The DRB1 gene, particularly position 57 of the DR beta-chain, may contribute to IDDM susceptibility in Japanese.

Adolescent↗
PubMed1990

[HLA and otosclerosis].

The HLA antigens frequencies were studied in 30 Japanese patients with otosclerosis, and were compared with those of 220 randomly-selected apparently healthy unrelated Japanese. Serological HLA typing was performed by the modified two-stage complement-dependent microcytotoxicity method at the Blood Transfusion Service, Tokyo University Hospital. The results were as follows: There was no significant deviation of HLA class I antigen frequencies in the patients tested as compared with those in controls. As for HLA class II antigens, the DRw11 antigens frequency showed slight increase; however, after the correction of the P value, this was not significant.

Adult↗
PubMed1989

Putative amino acid sequence of HLA-DRB chain contributing to rheumatoid arthritis susceptibility.

The association between HLA-DR4 and rheumatoid arthritis (RA) has been established in many ethnic groups. To clarify the determinant of susceptibility to RA, a polymorphic segment of the HLA-DRB gene was amplified in vitro by polymerase chain reaction and analyzed with oligonucleotide probes specific for the HLA-DR4 DNA sequences. A particular sequence encoding amino acids Gln70-Arg71-Arg72-Ala73-Ala74 showed a strong association with RA (p less than 0.005, relative risk 6.0). This amino acid sequence occurs in the DRB molecules with three RA-associated specificities, DR4/Dw14, DR4/Dw15, and DR1. DR4/Dw4, which is common in Caucasian RA patients, has a strikingly similar amino acid sequence Gln70-Lys71-Arg72-Ala73-Ala74 in terms of polarity and charge profiles. Other RA nonassociated sequences differ from this sequence by at least one amino acid substitution that causes the change of the net charge. The composition of amino acid residues at the positions 70-74 may play a crucial role in the pathogenesis of RA.

Amino Acid Sequence↗
PubMed1989

Human leukocyte antigen in childhood unilateral deafness.

Human leukocyte antigen frequencies were examined in 40 Japanese patients with severe unilateral sensorineural hearing loss found in childhood. Human leukocyte antigen-Bw54 was significantly increased in frequency. No statistically significant deviation in the Bw54 frequency was observed among several possible subgroups studied. Although this group of patients may have various causes, and underlying mechanism is still unclear, this preliminary study suggests that childhood unilateral deafness may be associated with a genetically determined factor(s).

Child↗
PubMed1989

Association of complement alleles C4AQ0 and C4B5 with rheumatoid arthritis in Japanese patients.

We investigated polymorphisms of complement components C2, C4, and factor B (BF) in Japanese patients with rheumatoid arthritis (RA). The frequencies of C4AQ0 (32.1%) and C4B5 (35.9%) among RA patients were significantly higher than among healthy control subjects. C4B5 was strongly associated with HLA-Bw54, Bw59, DR4.1, and DQw4. C4AQ0 showed no association with HLA-Bw54 or Bw59, but there was weak association with HLA-DR4.1 and DQw4. The number of persons with both C4AQ0 and C4B5 was significantly higher in the RA patient group (relative risk 13.5). C2C and BFS were the most common alleles in RA patients, as well as in healthy control subjects. These data support the existence of 2 different putative susceptibility haplotypes (HLA-Bw54 or Bw59;C2C; BFS;C4A3;C4B5;DR4.1;DQw4 and C2C;BFS; C4AQ0;C4B1 or C4B2) in Japanese patients with RA.

Alleles↗
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

Determination of an appropriate size of unrelated donor pool to be registered for HLA-matched bone marrow transplantation.

HLA-matched bone marrow transplantation from related or unrelated donors appears to be effective. To supply HLA-matched bone marrow for patients who do not have HLA-matched family donors, registration of unrelated HLA-typed donors and selection of matched donors will be necessary. In this study, the frequencies of each possible HLA phenotype and of corresponding, potentially matched donors were calculated by a computer from the table of frequencies of HLA-A, -B, and -DR haplotypes using data from 300 families in Japan and from the Eighth International Histocompatibility Workshop for European and North American whites. Appropriate sizes of such donor pools were evaluated theoretically in the Japanese population and in European and North American whites. To enable more than 80 percent of patients to have at least one identical donor, only 50,000 potential donors would be necessary for Japanese persons, whereas 1,000,000 and 400,000, respectively, would be required for European and North American whites.

Blood Donors↗
PubMed1989

Susceptibility epitope on HLA-DR beta chain for rheumatoid arthritis and the effect of the positivity on the clinical features.

A highly significant association of an amino acid sequence, '70Q71R72R73A74A' located on the DR beta-1 chain, with rheumatoid arthritis (RA) was confirmed in Japanese patients using polymerase chain reaction. The '70QRRA74A' is the most plausible candidate of susceptibility epitope in Japanese RA patients. The patients carrying the sequence showed slightly higher but not significant familial incidence. The positivity of the 'QRRAA' showed no effect on the positivity of the rheumatoid factor, rheumatoid nodules, and extra-articular signs. Also no significant differences in other clinical parameters (ESR, CRP, Hb, A/G) and age at onset were observed regarding the positivity. The risk that the 'QRRAA' positive subjects would suffer from RA was estimated to be about 1.3% which meant 7.2 times easier to get RA than those without 'QRRAA'.

Adult↗
PubMed1989

[Studies of the treatment of recurrent abortion with husband's lymphocytes].

Thirty-two primary habitual aborters who had more than 3 abortions during the early stages of pregnancies without any known causes of habitual abortions were studied. The degree of HLA-DR compatibility of the patient couples was similar to that of 70 control couples. The patients were treated with intra-dermal injections of their husbands' lymphocytes 4 times every 2 weeks. The skin reactions at the sites of the injection were estimated 24 hours and 48 hours after the first and fourth injections. The mixed lymphocyte reaction (MLR) after the last injection decreased in the patients whose skin reaction was weaker following the last injection than the first (p = 0.007), and these patients had a good prognosis for subsequent pregnancies (p = 0.010). On the other hand, the MLR after the last injection did not weaken in the patients whose skin reaction did not become weaker (p = 0.007), and in these patients abortion resulted in subsequent pregnancies (p = 0.010). The HLA-DR compatibility of the patient couple and anti-HLA-DR antibody induced by the treatment did not affect the prognosis for subsequent pregnancies.

Abortion, Habitual↗
PubMed1989

[Genetic variants of the complement components and HLA-antigens associated in patients with psoriasis vulgaris in Japanese].

Genetic polymorphisms of the serum complement components (C2, C4, C6, and C7) and HLA-antigens were studied in Japanese patients with psoriasis vulgaris. Among these complement components, positive associations with C4A4 and C4B2 were obtained. In addition to the previously reported haplotypes HLA-Cw6-B13 and Cw6-Bw57-DR7, the extended haplotype HLA-Cw11-Bw46-C4A4. 4B2-BFS-C2C-DRw8 may be a high risk haplotype in Japanese patients with psoriasis vulgaris.

Asian People↗
PubMed1988

A role of HLA-DQ molecules of stimulator-adherent cells in the regulation of human autologous mixed lymphocyte reaction.

In this study, we have found that treatment of stimulator autologous adherent cells with anti-HLA-DQ mAb resulted in markedly enhanced proliferative response of T cells in human autologous mixed lymphocyte reaction system wherein T cells were cultured with autologous adherent cells at near ratio of adherent cells to T cells in peripheral blood, in which T cells minimally proliferate. However, treatment of stimulator-adherent cells with anti-HLA class I, anti-DR and anti-DP mAb had no effect on the proliferative response of T cells under the condition. It was further observed that CD4-enriched cells could significantly proliferate in the presence of autologous adherent cells either untreated or treated with anti-DQ mAb, although treatment of adherent cells with anti-DR mAb blocked proliferative response of CD4-enriched cells. Moreover, the proliferative response of CD4-enriched cells was suppressed by addition of CD8-enriched cells in the presence of untreated adherent cells, whereas the proliferative response of CD4-enriched cells could not be suppressed by CD8-enriched cells when the adherent cells in the culture were treated with anti-DQ mAb. These observations suggest that CD8 T cells are required for suppression of proliferative response of CD4 T cells to HLA-DR molecules on autologous stimulator-adherent cells, and that HLA-DQ molecules on the surface of adherent cells play an important role in the induction of suppression by CD8 T cells.

Antibodies, Monoclonal↗
PubMed1988

An HLA-D region restriction fragment associated with refractory Behçet's disease.

We examined the association between HLA-DQ and refractory Behçet's disease at the genomic DNA level. Using a restriction endonuclease Taq I and a DQ beta cDNA probe, we identified the 1.9 kb DQ beta restriction endonuclease fragment tightly associated with refractory Behçet's disease. This observation indicates that genomic HLA-DQ variations affect the development of refractory Behçet's disease.

Behcet Syndrome↗
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↗