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N Mizuki

Publications and source records attributed to N Mizuki.

89 records · Page 5Linked to original sources
PubMed1992

Mouse submandibular glands express an androgen-regulated transcript encoding an acidic epididymal glycoprotein-like molecule.

Acidic epididymal glycoprotein (AEG) is an androgen-regulated, epididymal secretory protein assumed to be involved in sperm maturation. In the present study, we show that the mouse submandibular gland (SMG) expresses two genes designated Aeg-1 and Aeg-2. The nucleotide sequence of Aeg-1 cDNA clones was identical to that of epididymis-expressed Aeg cDNA clones, indicating that Aeg-1 is expressed in both epididymides and SMGs. The second, more abundant transcript, Aeg-2, had a sequence similar to, but distinct from, that of Aeg-1, and was not detectable in the epididymis. The level of Aeg-1 and Aeg-2 transcripts in the SMG was androgen-regulated and showed sexual dimorphism. In situ hybridization of SMG sections showed that Aeg-1 and Aeg-2 transcripts are produced by the cells of granular convoluted tubules. The C-terminal cysteine-rich region of the mouse AEG-2 molecule appears to have diverged faster than that of the mouse AEG-1 molecule, consistent with the idea that this region may play a role unique to the protein of the male reproductive system.

Amino Acid Sequence↗
PubMed1992

Association of HLA-B51 and lack of association of class II alleles with Behçet's disease.

Eighty-one Behcet's disease patients have been studied for HLA association by HLA-DRB1, -DQA1, -DQB1 and -DPB1 genotyping with the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique and for NcoI RFLP in the tumor-necrosis factor (TNF beta) gene by Southern hybridization in addition to serological typing. In serological typing, the frequency of HLA-B51 was significantly increased in the patients. In PCR genotyping, there was a significant increase in the HLA-DRB1*0802, DQA1*0301 and DQB1*0303 alleles, whereas the frequencies of DRB1*1502, DQA1*0103, DQA1*0101, DQB1*0601 and DQB1*0501 showed a significant decrease in the patients. No significant difference was observed in any HLA-DPB1 alleles. Among them, B51 was found to be a genetic marker most strongly associated with Behcet's disease (p less than 0.00005, chi 2 = 46.47, pc[corrected p] less than 0.005). The positive and negative associations of class II alleles with the disease can be explained by linkage disequilibrium with B51, and do not reach statistical significance by the corrected p-value test. In NcoI RFLP typing in the TNF beta gene, 250 kb centromeric of the HLA-B gene, the frequency of a 5.5 kb fragment was considerably decreased in the patients when compared to the controls, although the decrease was not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Alleles↗
PubMed1992

RFLP analysis in the TNF-beta gene and the susceptibility to alloreactive NK cells in Behçet's disease.

Behçet's disease is known to be associated with HLA-B51. To address the possibility that a non-human leukocyte antigen (HLA) gene closely linked to the HLA-B gene, such as tumor necrosis factor (TNF)-alpha, TNF-beta, or ECl (the locus that determines the susceptibility to alloreactive natural killer [NK] cells), is involved in the susceptibility to Behçet's disease, NcoI and EcoRI restriction fragment length polymorphisms in the TNF-beta gene and the susceptibility to lysis by alloreactive NK cells were investigated in Behçet's patients. In our NcoI restriction fragment length polymorphism (RFLP) analysis in the TNF-beta gene, the frequency of the NcoI 5.5 kb homozygote was decreased considerably in the patients, especially those with the ocular lesions, in relation to the healthy controls. However, no significant difference was observed between these groups in the EcoRI RFLP band distribution in this gene or the in susceptibility to lysis by alloreactive NK cells. These results indicated that a non-HLA gene located around the TNF gene region centromic of the HLA-B gene was a candidate to control the genetic susceptibility to Behçet's disease.

Base Sequence↗
PubMed1992

Human leukocyte antigen serologic and DNA typing of Behçet's disease and its primary association with B51.

Ninety Japanese patients with Behçet's disease (BD) were typed for human leukocyte antigen (HLA)-DRB1, -DQA1-, -DQB1, and -DPB1 alleles by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method and for HLA-A, -B, -C, -DR, and -DQ antigens by conventional serologic typing. Serologic HLA typing showed a remarkably significant increase of HLA-B51 and a significant decrease of HLA-DQw1 in the patients with BD, especially those with ocular lesions including complete type, as compared with the control group (for B51, chi-squared = 46.75, P corrected < 0.001, relative risk [RR] = 7.9; for DQw1, chi-squared = 12.10, P corrected < 0.01, RR = 0.4). By PCR-RFLP genotyping, no significant difference was revealed in any class II alleles between the patient and the control groups in the corrected P value test, but P value analysis showed the significantly high frequency of DRB1*0802 and the significantly low frequencies of DQA1*0103, DQB1*0601, and DQB1*0501. No significant difference was observed in any DPB1 alleles by either P value analysis. These results indicated that the primary and primordial gene(s) responsible for the susceptibility to BD, especially related to ocular lesions, were not located in the HLA class II gene region but were in or very close to the HLA-B locus in the class I region. They also suggested the possibility that BD was a symptom complex associated with some independent diseases.

Alleles↗
PubMed1992

1,25-Dihydroxyvitamin D3 down-regulation of HLA-DR on human peripheral blood monocytes.

The regulatory activity of 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) on human leucocyte antigen (HLA)-DR (MHC class II) antigen expression in monocytes from normal human peripheral blood was examined. Using forward light and side scatter by flow cytometry most cells within the discrete monocyte area expressed high levels of HLA-DR antigens following 4-day culture in medium alone (culture-enhanced HLA-DR) and expression was further up-regulated in the presence of interferon-gamma (IFN-gamma) (IFN-gamma-enhanced HLA-DR). Treatment with 1,25-(OH)2D3 markedly inhibited both culture and IFN-gamma-enhanced HLA-DR but not HLA-ABC (MHC class I). This 1,25-(OH)2D3 inhibition was as effective as PGE2 and hydrocortisone. To ascertain if HLA-DR was specifically down-regulated on monocytes, the effect of vitamin D3 analogues in CD33+ cells was examined. Incubation of the CD33+ cells with 1,25-(OH)2D3, 24-25-(OH)2D3 and 25-OHD3 resulted in dose-dependent inhibition of culture-enhanced HLA-DR paralleling the vitamin D3-receptor affinities of these compounds. Northern analysis also demonstrated that 1,25-(OH)2D3 treatment markedly decreased both expression of culture-enhanced and IFN-gamma-enhanced HLA-DR beta chain messenger RNA (mRNA) in monocyte-enriched populations. In total, our findings are consistent with the proposal that vitamin D3 analogues can contribute to down-regulating immune responses as a consequence of inhibiting class II expression.

Antigens, CD↗
PubMed1992

[Gene organization of HLA and its association with ocular disease].

It is now evident that the human major histocompatibility complex (MHC), human leucocyte-associated antigen (HLA), regulates the immune response through discrimination between autologous and non autologous substances thereby displaying a high degree of genetic polymorphism. In recent years, the three-dimensional structure of HLA has been clarified by crystal analysis and provides the attractive hypothesis, the so-called hotdog model, explaining the interactions of foreign antigens (or autologous antigens), HLA and T cell receptors and has a great impact on various studies on immunogenetic mechanisms underlying the development of many diseases. Thus, several HLA-associated ocular diseases such as Behçet's disease and Harada's disease have also been analyzed from this point of view by means of recombinant DNA techniques, enabling elucidation of molecular mechanisms of susceptibility to these diseases. This paper describes a general outline of HLA, especially its genetical structure, as well as recent analysis of molecular mechanisms of the predisposition to representative ocular diseases.

Eye Diseases↗
PubMed1991

Modified PCR-RFLP method for HLA-DPB1 and -DQA1 genotyping.

We previously developed a new technique for HLA class II genotyping by digestion of polymerase chain reaction-amplified genes with restriction endonucleases (PCR-RFLP method). This PCR-RFLP method is an efficient and convenient typing technique for class II alleles. However, small fragments or bands located close to each other on polyacrylamide gels sometimes prevent precise analysis of the RFLP bands. Furthermore, the restriction enzymes we have reported in the previous papers are not sufficient to identify the genotypes of all heterozygous individuals. Here, we report an improved PCR-RFLP method using some informative restriction enzymes which have either a single cleavage site or, alternatively, no cleavage site in the amplified DNA region, depending on the HLA alleles, making reading of RFLP band patterns much easier. Each second exon of the HLA-DQA1 or -DPB1 gene was selectively amplified from genomic DNAs of 70 HLA-homozygous B-cell lines and 100 healthy Japanese by PCR. Amplified DNAs were digested with restriction endonucleases and then subjected to electrophoresis assaying simply for cutting, or no cutting, of the DNA. ApaLI, HphI, BsaJI, FokI, MboII and Mn1I can discriminate eight alleles of the DQA1 gene. Similarly 19 alleles of the DPB1 gene can be discriminated with Bsp1286I, FokI, DdeI, BsaJI, BssHII, Cfr13I, RsaI, EcoNI, and AvaII enzymes. This modified PCR-RFLP method can be successfully applied to heterozygotes. Thus, the method is technically simpler and more practical for routine HLA typing work than our previous PCR-RFLP method.

Alleles↗
PubMed1991

[Immunogenetic mechanism of Behçet's disease].

In order to investigate the immunogenetic mechanism of Behçet's disease, frequencies of HLA antigens were studied in patients. The subjects consisted of 66 patients and 99 normal controls. A lymphocyte cytotoxicity test was used for typing HLA-A, -B, -C, -DR, -DQ antigens. HLA-DP antigens were analyzed by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. A significant increase of HLA-B15 was observed in the patients. In contrast, no significant difference was observed in HLA-Bw52 which possesses only two different amino acids from HLA-B15. On the contrary, frequencies of HLA-A11, HLA-Aw33, HLA-B35, HLA-B44 and HLA-DQw1 were significantly lower in the patients than in the controls. No significant difference was observed in HLA-DP antigens. These results suggest that Behçet's disease involves both disease susceptibility factors and disease resistance factors and that such genetic factors are mapped within or very close to the HLA-B gene in the class I gene region. Additionally class II HLA-DQ antigen is associated with disease resistance factors.

Amino Acid Sequence↗
PubMed1989

Molecular cloning and nucleotide sequence of rat brain argininosuccinate lyase cDNA with an extremely long 5'-untranslated sequence: evidence for the identity of the brain and liver enzymes.

Argininosuccinate lyase (EC 4.3.2.1) is an enzyme present in the brain of ureotelic animals. Using as a probe rat liver argininosuccinate lyase cDNA, already isolated and sequenced (Amaya, Y., Matsubasa, T., Takiguchi, M., Kobayashi, K., Saheki, T., Kawamoto, S. and Mori, M., J. Biochem., 103 (1988) 177-181), we screened a rat brain cDNA library constructed in the lambda gt11 expression vector and obtained a single cDNA clone. This cDNA clone contained an open reading frame encoding a polypeptide of 461 amino acid residues (predicted Mr = 51,390), a 5'-untranslated sequence of 967 bp and a 3'-untranslated sequence of 74 bp. The length of the 5'-non-coding region of the cDNA seems to be one of the longest among the cDNAs heretofore isolated. A comparison of the brain cDNA sequence (2424 bp) with the corresponding region of the liver cDNA (1574 bp) revealed differences in 5 nucleotides. The brain clone contained A----G and C----G base differences from the hepatic sequence, resulting in amino acid changes from Tyr and Arg in the liver clone, to Cys and Gly in the brain clone, respectively. The other 3 nucleotide differences are silent with respect to the amino acid sequence of the protein. Therefore, the amino acid sequence of the brain argininosuccinate lyase, as deduced from the nucleotide sequence of its cDNA clone, was identical with that of the liver protein, except for two amino acid residues. These minor changes may reflect a microheterogeneity of the argininosuccinate lyase gene. The brain and liver enzymes seem to be encoded by the same structural gene.

Amino Acid Sequence↗
PubMed1988

Suppressor T cells in mice made unresponsive to skin allografts.

We have induced suppressor T cells (Ts), capable of delaying allogeneic skin graft rejection, through the intravenous administration of allogeneic spleen cells under normal conditions. H-2 and non-H-2 incompatibility between recipient mice and donor skins induced strong graft rejection. However, when the Ts were transferred into recipient mice, the mean survival time was prolonged for every combination between recipient mice and donor skin. Studies using several strains of congenic mice revealed the antigen specificity of these Ts. Treatment with monoclonal anti-Lyt-2.2 or anti-Thy-1.2 antibody and complement abolished the suppression shown by the Ts of skin graft rejection. The suppression induced by these Ts, however, was resistant to treatment with monoclonal anti-Lyt-1.2, anti-L3T4, or anti-I-A antibody and complement. These results showed that the Ts were Lyt-1-2+, L3T4-, Ia-, T cells.

Animals↗
PubMedDate not supplied

Genetic relationships among Japanese, northern Han, Hui, Uygur, Kazakh, Greek, Saudi Arabian, and Italian populations based on allelic frequencies at four VNTR (D1S80, D4S43, COL2A1, D17S5) and one STR (ACTBP2) loci.

The genetic polymorphism at four variable number of tandem repeats (D1S80, D4S43, COL2A1, D17S5) and one short tandem repeat (ACTBP2) loci was assessed by polymerase chain reaction analysis of genomic DNA obtained from blood samples of eight human populations (Japanese, Northern Han, Hui, Uygur, Kazakh, Saudi Arabian, Greek, Italian). Allele frequencies at all loci were in the Hardy-Weinberg equilibrium for each population. With the exception of ACTBP2, the allelic distribution patterns for these loci revealed a marked genetic divergence among the eight populations. A dendrogram constructed by the neighbor-joining method based on the allele frequencies of the five loci suggested that the five Asian populations (Japanese, Northern Han, Hui, Uygur, and Kazakh) formed one cluster, whereas the two European populations and one West Asian population (Italian, Greek, and Saudi Arabian) formed another. The genetic relationship among these populations may have been greatly influenced by admixture as a result of the migration of individuals along the Silk Road throughout history.

Alleles↗
PubMedDate not supplied

Immunogenetic studies of Behçet's disease.

Behçet's disease has been shown to be strongly associated with the human leukocyte antigen (HLA) B51, not only in the Japanese but also in many other ethnic groups living in the area that extends from the Middle East to Japan. Specific antigen presentation by B51 molecules may be involved in the development of Behçet's disease. Furthermore, studies of the HLA-C genotype conducted using a polymerase chain reaction-sequence specific primers method have suggested that the gene involved in the pathogenesis of Behçet's disease is not the HLA-C gene but some other gene located near the HLA-B gene. Polymorphic analysis of the Tau-a microsatellite located between the HLA-B and TNF genes have also indicated that the Behçet's disease gene is located near the HLA-B gene but is not the HLA-B51 gene itself. We and others believe that many important genes exist in the region located between the TNF and HLA-B or HLA-C genes, including the MIC, PERB, and NOB genes. In this paper, we review current data on genetic factors involved in the development of Behçet's disease.

Behcet Syndrome↗