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Biomedical subjects

K Kano

Publications and source records attributed to K Kano.

At least 163 records · Page 9Linked to original sources
PubMed1991

T cell can recognize the allospecificities formed by the substitution of amino acids associated with HLA-Bw4/Bw6 public epitopes.

Our previous studies clearly showed that HLA-B35 and HLA-Bw53 differed only by the amino acids associated with HLA-Bw4/Bw6 epitopes, in that the former possessed Bw6 and the latter Bw4 epitope. It remains to be known whether T cell can discriminate HLA-B35 from HLA-Bw53, although the difference between these HLA antigens is discriminated by monospecific human alloantisera. To investigate allorecognition of these HLA antigens by T cells, anti-HLA-Bw53 cytotoxic T lymphocytes (CTLs) were generated. Anti-HLA-Bw53 cytotoxic T lymphocytes (CTLs) were generated. Anti-HLA-Bw53 bulk CTLs from an individual with HLA-B35 clearly discriminated HLA-Bw53 from HLA-B35. On the other hand, anti-HLA-Bw53 bulk CTLs from an individual without HLA-B35 revealed weak cross-reactivity with HLA-B35 and HLA-B51. The additional studies using HLA-Bw53 or HLA-B35-specific CTL clones showed that some but not all of the CTL clones definitively distinguish the difference between HLA-Bw53 and HLA-B35. Thus, the allospecificities formed by HLA-Bw4/Bw6 epitopes were discriminated by allogeneic T cells. The present study demonstrated that HLA-Bw4/Bw6 public epitopes play an important role in allorecognition of T cells.

Amino Acid Sequence↗
PubMed1991

[A study of falls experienced by the aged among users of preventive health examination services].

In order to determine what factors are related to falls and the effect on the aged, a study was conducted on subjects aged 60 years and over who had undergone preventive health examinations in the western region of Shizuoka Prefecture. Subjects (n = 305) had an average age of 64.4 +/- 3.8 years, and all were interviewed regardless of their history of falls. For the 66 cases who had experienced falls, further questions prepared in advance, were included. The following results were obtained: 1) There were 66 subjects (21.6% of the subjects) who had experienced falls with some experienced multiple falls for a total count of 91 falls. 2) The frequency of falls of female subjects was significantly higher than that of males. Further, with respect to the type of injuries suffered, in the case of many of the female subjects, these took the form of contusions. 3) The majority of subjects who experienced falls were engaged in farming and most of the falls were work-related. 4) Results of this study showed that, while not statistically significant, cerebrovascular diseases are closely connected to falls and increases the falls coefficient among the aged.

Accidental Falls↗
PubMed1990

Functional expression of HLA-C blank antigens on human blood lymphocytes.

The surface expression of two HLA-C blank Ag (Cb-1 and Cb-2) on PBL was investigated with Cb-1- and Cb-2-specific CTL clones generated by the stimulation of the HLA-C blank Ag on transfected Hmy2CIR cells. The Cb-1- and Cb-2-specific CTL clones could lyse EBV-transformed B cells and PHA-induced T cells from which the HLA-C blank genes were derived. Furthermore, the reactivity of these CTL clones with PHA-induced T cells was blocked by HLA class I monomorphic mAb. These results demonstrated that the HLA-C blank Ag are expressed on the surfaces of PBL. Thus, despite the fact that the HLA-C blank Ag are expressed on normal PBL, they are incapable of generating corresponding alloantibodies. On the other hand, the present study demonstrated that these Ag on normal PBL are able to induce specific CTL and that the capacity of these Ag to induce allogeneic CTL is almost identical to that of HLA-B Ag, indicating that they may function as alloantigens in vivo and play a significant role in the rejection of organ grafts and in the graft-versus-host reaction in bone marrow transplantation.

B-Lymphocytes↗
PubMed1990

The allorecognition of H-2Kb-specific CD4-CD8- T cell hybridomas is influenced by the substitution at residue 256 of MHC class I molecules.

Our previous studies demonstrated that allorecognition of HTB176.10 and HTB177.2, H-2Kb-reactive CD4-CD8- T cell hybridomas is markedly influenced by the exchange of the alpha 3 domain between H-2Kb and H-2Dp. The recombinant genes of the exon 4 between H-2Kb and H-2Dp were constructed to determine the residues of the alpha 3 domain that influence the allorecognition of these T cell hybridomas. Seven recombinant genes of the exon 4 were generated by in vivo recombination in Escherichia coli. Chimeric genes containing these recombinants were transfected into L cells and the transfectants expressing equivalent amounts of chimeric molecules were selected by flow cytometry. Studies on responses of these T cell hybridomas to the chimeric molecules confirmed our previous observation that the primary structure of the alpha 3 domain influences the allorecognition by the hybridomas. Moreover, it was indicated that residue 256 on the alpha 3 domain markedly affects the allorecognition by the T cell hybridomas, although substitutions at residues 184, 193, 195, 197, 262, and 264 exerted some effects on the T cell recognition. Further studies with the use of a single amino acid mutant of H-2Kb at residue 256 confirmed the effect of substitution at residue 256 on allorecognition of the T cell hybridomas. Taken together, results of this study demonstrated that polymorphism of the alpha 3 domain is indeed involved in the formation of allodeterminants recognized by TCR.

Amino Acid Sequence↗
PubMed1990

Allodeterminants and evolution of a novel HLA-B5 CREG antigen, HLA-B SNA.

A novel HLA-B5 CREG gene, HLA-B SNA was cloned and the primary structure was determined. The sequence data showed that HLA-B SNA was identical to HLA-B51 except the alpha 1 domain in which one amino acid substitution at residue 74 and 5 amino acid substitutions associated with the Bw4/Bw6 epitopes were observed between these Ag. The comparison with other HLA-B locus genes suggested that HLA-B SNA evolved from HLA-B51 by gene exchange or recombination at the exon 2 between HLA-B51 and B8. A total of 10 of 14 HLA-B51-specific CTL clones showed significantly weak or no recognition of HLA-B SNA Ag. They also gave the same degree of a lysis of Hmy2CIR cells expressing the HLA-B35/51 chimeric Ag composed of the alpha 1 domain of HLA-B35 and other domains of HLA-B51 as that of Hmy2CIR cells expressing the HLA-B SNA Ag. These results demonstrated that amino acid substitutions within positions 77-83 associated with the HLA-Bw4/Bw6 epitopes have an influence on recognition of the HLA-B SNA antigen by HLA-B51-specific CTL.

Alleles↗
PubMed1990

Presentation of human minor histocompatibility antigens by HLA-B35 and HLA-B38 molecules.

Cytotoxic T lymphocyte (CTL) clones specific for human minor histocompatibility antigens (hmHAs) were produced from a patient who had been grafted with the kidneys from his mother and two HLA-identical sisters. Of eight CTL clones generated, four recognized an hmHA (hmHA-1) expressed on cells from the mother and sister 3 (second donor); two recognized another antigen (hmHA-2) on cells from the father, sister 2 (third donor), and sister 3; and the remaining two clones recognized still another antigen (hmHA-3) on cells from the father and sister 3. Panel studies revealed that CTL recognition of hmHA-1 was restricted by HLA-B35 and that of hmHA-2 and hmHA-3 was restricted by HLA-B38. The HLA-B35 restriction of the hmHA-1-specific CTL clones was substantiated by the fact that they killed HLA-A null/HLA-B null Hmy2CIR targets transfected with HLA-B35 but not HLA-B51, -Bw52, or -Bw53 transfected Hmy2CIR targets. These data demonstrated that the five amino acids substitutions on the alpha 1 domain between HLA-B35 and -Bw53, which are associated with Bw4/Bw6 epitopes, play a critical role in the relationship of hmHA-1 to HLA-B35 molecules. The fact that the hmHA-1-specific CTLs failed to kill Hmy2CIR cells expressing HLA-B35/51 chimeric molecules composed of the alpha 1 domain of HLA-B35 and other domains of HLA-B51 indicated that eight residues on the alpha 2 domain also affect the interaction of hmHA-1 and the HLA-B35 molecules.

Antigen-Presenting Cells↗
PubMed1990

Discrimination of HLA-B5 crossreactive group antigens by human allospecific CTL clones.

Human CTL clones discriminating serologically closely related HLA-Bw52, B51, and B35, which belong to HLA-B5 crossreacting group (CREG), were established from peripheral blood lymphocytes by repeated in vitro stimulations. Five HLA-Bw52-specific CTL clones from an individual with HLA-B5 CREG antigens and four CTL clones from another individual with HLA-B51 were generated. The specificity of these CTL clones was ascertained by their lysis of EBV-transformed B cells with HLA-Bw52, but not those with HLA-B51 or B35, and Bw52-transfected Hmy2CIR cells but not HLA-B51 or B35 transfectants. Conversely HLA-B51-specific clones were generated from the HLA-B5 CREG-negative individual, as well as another individual with HLA-Bw52. Their specificity was determined in a similar fashion. Since HLA-B51 differed from HLA-Bw52 only by two amino acid substitutions on the alpha helical region of the alpha 1 domain, these results demonstrated that allospecific CTLs can be produced and discriminate the epitopes formed by the subtle difference in the structure of these HLA class I molecules. Furthermore, three HLA-B35-specific CTL clones were generated from the HLA-B5 CREG-negative individual that discriminated HLA-B35 from HLA-Bw52 and B51. Taken together these results demonstrated that human CTL clones could definitively discriminate the three serologically related HLA-B5 CREG specificities.

Clone Cells↗
PubMed1990

Depression in members of a new religious sect in Japan.

We investigated 226 people belonging to a regional church of a new religious sect (hereinafter referred to as religious group) and 899 ordinary people living in the rural area near this church (hereinafter referred to as nonreligious group) with a questionnaire using Zung's Self-Rating Depression Scale (SDS). In males ranging in age from 40 to 69, the mean scores of 7 SDS items out of 20 were significantly higher in the religious group than in the nonreligious group. Males at the age of 70 or older in both groups, however, did not show any significant difference in these items. It suggests that the religious affiliation exerted mentally good effects on the older male members.

Adaptation, Psychological↗
PubMed1990

Antigenic determinant of a monoclonal antibody: extracellular domain at the M3-M4 junction of the alpha-subunit of Na,K-ATPase.

The binding site of a monoclonal antibody, M45-80, against the alpha-subunit of horse Na,K-ATPase was determined. Various sizes of DNA fragments derived from rat Na,K-ATPase alpha 1-subunit cDNA were cloned into pUC19 expression vector and some fragments of horse genomic DNA were cloned into pUC18. Escherichia coli JM83 cells harboring the plasmids were grown and the cell lysates were used as antigens. An enzyme-linked immunosorbent assay revealed that M45-80 recognizes the hexapeptide Glu-Tyr-Thr-Trp-Leu-Glu (which is identical to the rat and horse alpha 1-subunits) at the M3-M4 junction located on the extracellular side. The ouabain-binding site is discussed in relation to the recognition site of M45-80.

Amino Acid Sequence↗
PubMed1990

Hanganutziu-Deicher antigen as a possible target for immunotherapy of melanoma.

Hanganutziu-Deicher (H-D) antigen is classified as a heterophile antigen and chemically defined as a glycoconjugate which contains N-glycolylneuraminic acid. H-D antigens are absent from normal human tissues, but can be expressed on a variety of human malignant cells, including melanoma. Natural anti-H-D antibodies have been detected in man with and without malignancies, but in this study when the level of antibody was compared between healthy adults and patients with melanoma, elevated anti-H-D antibody levels were found more frequently in melanoma patients for both IgM (p = 0.0001) and IgG (p = 0.0001). The present study was designed to evaluate the significance of the H-D antigen-antibody system in melanoma suppression. Sera from melanoma patients containing anti-H-D antibody reacted strongly to H-D antigen expressed on melanoma by means of flow cytometry. In a complement-dependent cytotoxicity assay this antibody killed melanoma cells in vitro. In vivo significance of the antibody was assessed by evaluating the relationship between the antibody levels and the clinical course in patients with stage II melanoma. Antibody levels were measured by enzyme-linked immunosorbent assay using a H-D glycoprotein antigen isolated from bovine erythrocytes. A significantly higher level of IgG (p = 0.0640) and IgM (p = 0.0644) anti-H-D antibody was demonstrated in those patients who were free of disease more than 5 years after surgery than in those who relapsed within 2 years. This study provides a rational basis for immunotherapy targeting H-D antigen in human melanoma.

Antibodies↗
PubMed1989

Purification and characterization of a growth factor from guinea pig harderian gland.

A polypeptide growth factor, Harderian gland-derived growth factor (HGDGF), has been purified approximately 43,000-fold from guinea pig Harderian gland by column chromatography on TSK gel DEAE-5PW, blue-Sepharose CL-6B, and Superose 12. The yield was approximately 10%. The Superose 12 fraction was further purified by Aquapore BU-300 reversed-phase chromatography to apparent homogeneity. HGDGF was eluted from TSK gel DEAE-5PW at 0.20-0.35 M NaCl, with a linear gradient of 0.15-0.80 M NaCl and at 2.20 M NaCl from blue-Sepharose CL-6B. The activity of HGDGF toward human embryonic cells (TIG-3) was quantitated, [3H]thymidine incorporation for 48 h being stimulated in a linear and dose-dependent manner. Purified HGDGF has a molecular weight of approximately 13,000, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and molecular sieve column chromatography. HGDGF is labile to treatment with SH reagents or acetic acid. Both trypsin digestion and boiling decrease the activity of HGDGF. Its pI is 5.1. HGDGF stimulates the multiplication of TIG-3 cells but has no effect on human endothelial cells K2T1 or A2T2 which require fibroblast growth factor for growth. HGDGF appears to differ from other growth factors, suggesting that it is a previously undescribed growth factor.

Animals↗