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R Hirata

Publications and source records attributed to R Hirata.

65 records · Page 4Linked to original sources
PubMed1985

Defective expression of HLA class I antigens: a case of the bare lymphocyte without immunodeficiency.

A case of the bare lymphocyte without apparent immunodeficiency was observed in a 33-year-old woman who had no history of severe infections but suffered from sino-bronchial disease. No HLA-A and -B antigens (class I antigens) were detected at the cell surface of lymphocytes, granulocytes, and platelets, but they were expressed, although at a reduced level, on the cultured B lymphoid cell line. T lymphocytes were normal in number and in the relative proportion of T4/T8 and responded to mitogens but not to PPD and candida. HLA-DR antigens (class II antigens) were present on B lymphocytes and showed intermediate MLR-stimulatory capacity, which made it possible to deduce the patient's HLA genotype. She was found to be homozygous at consanguinity for HLA-A, -B, and -DR antigens. The numbers of B lymphocytes, immunoglobulins, and complements were all in the normal range; there was, however, a low level of IgM. Two-dimensional gel analysis of class I antigens revealed the presence of normally expressed beta-2 microglobulins (B2M) and an apparently single set of class I heavy chains, allowing us to consider two alternative cellular mechanisms in this defect; the presence of one abnormal class I structural gene and the regulatory mechanism that acted in cis were suggested.

Adult↗
PubMed1984

Separation of four class II molecules from DR2 and DRw6 homozygous B lymphoid cell lines.

Four human class II molecules, one FA, one DC1, and two DR-like molecules, were isolated from DR2 and DRw6 homozygous cell lines by means of a variety of monoclonal antibodies and were compared with each other by two-dimensional (2-D) gel electrophoresis. Anti-DR2 or anti-DR3 + 5 + w6 sera immunoprecipitated two distinct light chains (L1 and L2) and one heavy chain (H1) from a DR2 or DRw6 homozygous cell line, respectively. One or both of these two class II molecules were also immunoprecipitated by "DR-specific" monoclonal antibodies and were considered to constitute a "DR" family of molecules. Three DC1-specific monoclonal antibodies, SDR4.1, Tu22, and PLM5, immunoprecipitated a set of heavy (H2) and light (L3) chains distinct from those of two DR-like molecules. The heavy chains of the DC1 antigens from DR2 and DRw6 cell lines were indistinguishable, whereas the light chains were structurally distinct from each other. A fourth molecule, FA, was identified by a novel monoclonal antibody and was also detected by two additional antibodies, Tu39 and SG171, that blocked the SB-specific T-cell proliferative response. The FA light chain (L4) was distinct from those of the former three antigens on both cell lines, whereas the FA heavy chain was indistinguishable from the DC1 heavy chain (H2) in this 2-D gel analysis. Thus, four light chains and two heavy chains were isolated from both DR2 and DRw6 homozygous cell lines. A possible gene-antigen organization of the DC-like antigens was also discussed.

B-Lymphocytes↗
PubMed1984

Two-dimensional gel analysis of a second family of class II molecules by polymorphic HLA-DR4,5, and w9 monoclonal antibodies.

Human Ia-like, class II molecules were isolated by immunoprecipitation with monoclonal antibodies from various HLA-D/DR homozygous cell lines and were analyzed by two-dimensional gel electrophoresis. The monoclonal antibody PLM12 reacted with B cells carrying DR4, DR5, DRw6.2, and DRw9 phenotypes, and its reactivity perfectly correlated with the previously defined TB21 (MB3-like) specificity. Class II molecules detected by PLM12 were structurally distinct from those precipitated by the anti-DR monoclonal antibody NC1 on all HLA-DR4, DR5, DRw6.2, and DRw9 homozygous cell lines and showed polymorphism in heavy and light chains among these cell lines. The monoclonal antibodies PLM2 and PLM9 only reacted with B cells carrying DR5 and DRw6.2 and also detected a distinct set of class II molecules from those precipitated by NC1 but identical to those of PLM12. Thus, PLM2 and PLM9 serologically detected a new subtypic antigen of the PLM12-reactive class II molecules. Furthermore, the antibody NC1 precipitated two light chains and one heavy chain from HLA-DRw6.2 homozygous cell line EBV-Sh. The result indicated the presence of three sets of class II molecules: two in a DR family and another carrying the polymorphic determinants detected by PLM2, PLM9, and PLM12 in a second family.

Animals↗
PubMed1984

Molecular identifications of HLA-DR4, MT3, and TB21 antigens on HLA-DR4 homozygous B cell lines.

The HLA-DR locus in the human major histocompatibility complex determines a series of polymorphic cell surface antigens; these antigens are composed of two noncovalently associated glycoproteins of 34,000 daltons and 29,000 daltons and are predominantly expressed on B cells, monocytes, and activated T cells (1). To date, 10 HLA-DR specificities have been well characterized by using alloantisera obtained from multiparous women (2). In addition to these DR antigens, two other B cell alloantigen systems (MT and MB) were proposed on the basis of the serologic data (3,4); the MB1 or MT1 specificities are found in association with DR1, DR2, and DRw6, whereas MT2 is associated with DR3, DR5, DRw6, and DRw8; MT3 is associated with DR4, DR7, and DRw9, and MB3 or MT4 is associated with DR4, DR5, and DRw8, respectively (3, 4). We have also described that the TB21 antigen is expressed in association with DR4, DR5, and DRw9 (5). The HLA-DR, MB, MT, or TB antigens are collectively referred to as class II antigens. The number of human class II antigens has been of primary concern because of their similarity to murine Ia antigens and especially because of their close relationship to certain diseases. With the aid of immunochemical means and alloantisera, it has been demonstrated that at least two loci control human class II molecules (6-10). The data presented in this report show the existence of three class II molecules carrying well-known allospecificities, DR4, MT3, and TB21, on HLA-DR4 homozygous cell lines.

Antigen-Antibody Reactions↗
PubMedDate not supplied

Combination therapy of laparoscopic cholecystectomy and endoscopic transpapillary lithotripsy for both cholecystolithiasis and choledocholithiasis.

This report describes five patients with cholecystolithiasis and choledocholithiasis who were treated by combination endoscopic extraction of common bile-duct stones with sphincterotomy (EST) and laparoscopic cholecystectomy (LC). Following this combination procedure the patients were relieved completely of obstructive jaundice and right upper quadrant pain, leaving only small trocar insertion scars made during the short course of hospitalization. The combination therapy of EST and LC will be recommended for this kind of patient as a minimally invasive procedure.

Adolescent↗
PubMedDate not supplied

Corynebacterium diphtheriae threats in cancer patients.

The aim of this study was to determine the bacteriological properties of Corynebacterium diphtheriae strains isolated from bronchiole washing and cancer lesions. Bacteriological characterization included fluorescence/double sugar urease (King/DSU) screening tests, pyrazinamidase (PYZ), CAMP-reactions and radial immunodiffusion toxigenicity assay. Microorganisms produced fluorescence under ultraviolet light and were catalase positive; urea and aesculin hydrolysis negative; fermentation of glucose, maltose and sucrose and no fermentation of mannitol and xylose; PYZ and CAMP reaction negative. The API-Coryne system was used for bacterial preliminary identification at local hospital laboratory and produced numerical profiles 1010325 and 0010325 for sucrose positive C. diphtheriae var. mitis (nitrate positive) and C. diphtheriae var. belfanti (nitrate negative), respectively. The hemagglutination, adherence to glass and polystyrene assays evaluated adhesive characteristics. Strains were toxigenic and able to adhere to glass, polystyrene and human erythrocyte surfaces (titer 4). C. diphtheriae strains isolated from cancer patients expressed adhesive characteristics similar to strains isolated from immunocompetent hosts. Circulation of toxigenic C. diphtheriae continues to present a threat for children and adults including patients with cancer in hospital environment. Laboratories should remain alert to the possibility of isolation of diphtheria bacilli from adults with neoplastic disease.

Adult↗