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H Tsuneyama

Publications and source records attributed to H Tsuneyama.

17 recordsLinked to original sources
PubMed2001

E variants found in Japanese and c antigenicity alteration without substitution in the second extracellular loop.

BACKGROUND: The molecular basis of E variants in the Japanese population is poorly understood. In this study, molecular analysis of E variants detected in Japanese by serologic methods was carried out. STUDY DESIGN AND METHODS: E variants from healthy Japanese blood donors were screened by serologic analysis using E MoAbs. Fifteen E variant samples were divided into three types--EFM, EKH, and EKK-on the basis of patterns of reactivity with five distinct E antibodies. The entire coding region of the Rh cDNAs from the E variant samples was analyzed by sequencing. RESULTS: Although the Rh cDNA sequences of the three types were different from each other, those of the EFM-type variants (RHEFM) had a partial DNA exchange in exon 5 between the RHCE and RHD genes, generating an RHcE variant (Gln233Glu, Met238Val). The cDNA of EKH-type variants (RHEKH) exhibited a point mutation (G461C) in exon 3 of the RHcE allele that resulted in an Arg154Thr substitution in the third external loop of the RhcE peptide. The EKK-type variant (RHEKK) carried a hybrid gene structure characterized by replacement of exons 1-3 (or 2-3) of the RHCE gene with those of the RHD gene. The RHD gene of a person possessing an E variant of the EKK type was also a hybrid gene, D-cE(2-3)-D or cE(1-3)-D (RHDKK). The E variants of types EKH and EKK showed weak c antigenicity. CONCLUSION: In serologic screening of 140,723 Japanese blood donors, 15 were found to possess E variants (0.011%). A new RHCE variant, RHEKH, was identified. On the basis of the variants found in this study, the c antigenicity seemed to be determined not only by Pro-103 but also by the structure of the third extracellular loop or the amino acids contained in it.

Amino Acid Substitution↗
PubMed2000

Three episodes of delayed hemolytic transfusion reactions due to multiple red cell antibodies, anti-Di, anti-Jk and anti-E.

There is no report in which three episodes of delayed hemolytic transfusion reaction (DHTR) occurred from multiple antibodies to red cells (RBCs) in the course of treatment of a patient. This paper describes episodes of anemia and hyperbilirubinemia in concert with the development of three alloantibodies in a multiple transfused patient. The patient was a 71-year-old male suffering from valvular heart disease and hemophilia B with a history of transfusions. Although he received compatible RBCs from 14 donors as judged by a crossmatch test using the albumin-antiglobulin method, three episodes of DHTR occurred after surgery. The first hemolytic episode on day 7 after surgery was due to anti-Di(a) because of clinical and laboratory evidence which included jaundice, sudden increases in total bilirubin (T-Bil) and lactate dehydrogenase (LD) levels, and a decrease (2.2 g/dl) in hemoglobin (Hb) level. The second hemolytic episode on day 16 resulted from newly producted anti-Jk(b). The patient experienced fever, fatigue, nausea and anorexia, and laboratory data showed a second increase in T-Bil, a second decrease (3 g/dl) in Hb, and moderate elevations of blood urea nitrogen (BUN) and creatinine (CRE) levels. The third hemolytic episode on day 39 was due to anti-E. The patient complained of fever and fatigue and had a third unexplained drop (1.5 g/dl) in Hb despite no bleeding. This is the first reported case in which three episodes of DHTR occurred from different red cell antibodies.

Aged↗
PubMed2000

Polymorphisms of RhD(Va) and a new RhD(Va)-like variant found in Japanese individuals.

BACKGROUND AND OBJECTIVES: Red cell type RhD(Va) lacks epD1 and 5 and is encoded by hybrid RHD-CE(5)-D alleles. We analyzed RhD(Va) and RhD(Va)-like samples in Japanese blood donors. MATERIALS AND METHODS: Ten RhD(Va) samples lacked epD1 and 5 and 3 RhD(Va)-like variants also lacked, epD2 and a part of 6/7. We identified the full-length nucleotide sequences of the complementary DNA (cDNA) synthesized from 4 samples: 3 of type D(Va) and the 4th a D(Va)-like variant. RESULTS: Although their sequences differed from each other, all the substitutions were exclusively in exon 5. Three D(Va) samples had hybrid RHD-CE(5)-D alleles, but the D(Va)-like variant had a unique nucleotide substitution with a single amino acid change, E233K. Exon 5 of the genomic DNA from all 13 samples was analyzed by sequencing. No other sequences were identified. CONCLUSION: All RhD(Va) and RhD(Va)-like variants had the substitution for E233. E233 seems to be a determinant of epD1 and 5. A new category of RhD variant, DYO, was identified.

Amino Acid Substitution↗
PubMed1998

Molecular cloning and characterization of decay-accelerating factor deficiency in Cromer blood group Inab phenotype.

An additional decay-accelerating factor (DAF) mutation, designated as Inab phenotype in the Cromer blood group system, was recently identified in a 28-year-old Japanese woman (H.A.). The red blood cells of H.A., like those of other Inab phenotype individuals, were negative for Cromer system antigens, Cra, Tca, Dra, UMC, and IFC. The deficiency of DAF on the red blood cells of H.A. has been shown by immunoblotting with a murine monoclonal antibody to DAF. Molecular analysis has shown that H.A. is homozygous for a single nucleotide substitution, C1579-->A, at the position 24 bp upstream of the 3'-end of exon 2 of the DAF gene. This substitution causes the activation of a novel cryptic splice site and results in the production of mRNA with a 26 bp deletion. The deletion introduces a reading frame shift and creates a stop codon immediately downstream of the deletion. Translation of mRNA would be terminated at the first amino acid residue of the second short consensus repeat (SCR2) domain (exon 3) of DAF. The functional domains of DAF's complement regulatory activity and the carboxy-terminal signal domains for glycosylphosphatidylinositol (GPI) anchoring are predicted to be lacking in H.A. Thus, there would be no DAF present on the cell surface.

Adult↗
PubMed1997

A new high-molecular-weight glycophorin C variant with a duplication of exon 2 in the glycophorin C gene.

Glycophorin C (GPC) and glycophorin D (GPD) are closely related sialoglycoproteins in the human red blood cell (RBC) membrane. Both are thought to be encoded by the GPC gene (GYPC). We report here the new GPC variant, MAT, with a high-molecular-weight form of GPC and GPD. The murine monoclonal antibody to GPC (CBC-96), which had specificity for the N-terminal region of GPC, gave a stronger reactivity with the MAT RBCs than did normal RBCs in direct agglutination tests. Immunoblotting of the MAT RBC membranes with anti-GPC antibodies showed the apparent molecular weight of GPC.MAT and GPD.MAT was 5000 greater than that of their normal counterparts. cDNA was synthesized from total RNA obtained from three unrelated, heterozygous MAT blood donors and analysed by the polymerase chain reaction with primers that spanned sequences encoded by GYPC. Two fragments were generated: one was 510 bp, the other was 453 bp and corresponded to the normal GPC. Sequencing of the mutant 510-bp fragment showed an insert of 57 nucleotides that corresponds to the entire sequence of exon 2 in GYPC. These results show that MAT is the result of a duplication of exon 2 in GYPC, which probably encodes the two high-molecular weight forms GPC.MAT and GPD.MAT. The MAT mutation is found with a frequency of 0.02% in the Japanese population.

Animals↗
PubMed1996

Family study of acute intermittent porphyria and hereditary coproporphyria in Niigata and Akita Prefectures, Japan.

Simple screening tests, urinary porphobilinogen (PBG) for acute intermittent porphyria (AIP) and fecal coproporphyrin for hereditary coproporphyria (HCP), were performed in a family study of AIP and HCP. Urinary PBG was positive in 93 of 211 members of 10 AIP families, but was negative in 568 of 572 controls. Fecal coproporphyrin was positive in 54 of 108 members of 10 HCP families, but was negative in 188 controls. A dominant inheritance was assumed by a chi-square test and Weinberg segregation ratio. Worsening factors around puberty were suggested by the onset age and cumulative percentage of genetically loaded cases. Sex-related expression of symptoms was also inferred by a higher incidence of both porphyrias in females than in males. Fitness and penetrance of both porphyrias were good. An l-triiodothyronine loading test was the most useful for the detection of masked carriers of AIP. In conclusion, AIP and HCP in Japan show a dominant inheritance with sex-related metabolic and clinical manifestations.

Adolescent↗
PubMed1996

Serological analysis of monoclonal anti-E and -e with Japanese E/e variant red cells.

The agglutination patterns have been analyzed for the reaction between 24 monoclonal antibodies (MAB) with specificity for the Rh antigen E or e and red cells of E/e variant from Japanese blood donors. The MABs were tested for direct agglutination of papain treated cells at 20 degrees C. The reactions of a full titration series of each MAB with a E/e variant cell were compared to the reactions of that MAB with normal E + e + cells. Sixteen anti-E were divided into a minimum of 6 different agglutination patterns with 8 examples of E variant cells. Eight anti-e gave a minimum of 5 different agglutination patterns with 6 examples of e variant cells.

Antibodies, Monoclonal↗