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N Yamaura

Publications and source records attributed to N Yamaura.

At least 19 recordsLinked to original sources
PubMed1992

Production and epidemiological application of monoclonal antibody specific for Salmonella O5-antigen.

Salmonella typhimurium is an important causative agent of acute gastroenteritis (food poisoning), and the decision of the source of infection urgently requires epidemiological investigation. There are two types of S. typhimurium, O5-antigen-carrier type (O5(+)-antigen type) and noncarrier type (Copenhagen antigen type). On the assumption that serological differentiation of the types is effective for epidemiological exploration for the source of infection, we produced a monoclonal antibody, TMY1, specific for the O5-antigen. We classified S. typhimurium identified as the causative agent of mass outbreaks of acute Salmonella gastroenteritis according to the O5-antigen type, by using the TMY1. As a result, the bacterium in each outbreak was classified as the O5(+)-antigen type or the Copenhagen antigen type based on the difference in reactivity with TMY1. S. typhimurium isolated from calves in mass outbreaks of diarrhea and from animals with various diseases were also classified by TMY1 according to the O5-antigen type, and TMY1 was found to be as useful as in human cases. From this confirmation, TMY1 was demonstrated to be useful as a marker for epidemiological investigation of the source of infection by the O5-antigen type of S. typhimurium.

Agglutination Tests↗
PubMed1990

Production and characterization of a human monoclonal antibody recognizing a new antigen expressed on some lymphoid cells.

A cell line secreting a human monoclonal antibody was established by Epstein-Barr virus transforming B cells derived from an enlarged cervical lymph node excised from a patient bearing a carotid body tumor. The reactivity of the monoclonal antibody, designated as mNISP, was tested on various cells and cell lines. An antigen defined by the mNISP was expressed on some Burkitt's lymphoma cell lines and on a non-T non-B acute lymphoblastic leukemia cell line. Furthermore, this antigen was expressed on leukemic cells from 2 of 8 patients with chronic myelocytic leukemia, 2 of 10 patients with acute myeloblastic leukemia, one of 13 patients with acute lymphoblastic leukemia, and two patients with adult T cell leukemia, but it was not expressed on normal T, B and adherent (macrophage) cells. In addition, mNISP reacted with T cells obtained from human T-cell leukemia virus type I carriers. We found that the antigen defined by mNISP was distinct from any previously reported antigen in terms of its pattern of cellular expression and molecular weight, suggesting that mNISP recognizes a new antigen expressed on some lymphoid cells.

Adolescent↗
PubMed1990

[Production and characterization of a monoclonal antibody specific for Salmonella O19-antigen].

A monoclonal antibody, SBY1 (IgM, kappa), against the Salmonella O-antigen was generated by using the myeloma cell line Sp2/O-Ag14 as a fusion partner with spleen cells from BALB/c mice immunized with S. senftenberg 963 K. SBY1 was characterized by the slide agglutination and absorption test. SBY1 was believed to show the specificity to O1-, O3- or O19-antigens of Salmonella because S. Senftenberg 963 K (O1, 3, 19) was used as the antigen for immunization. The slide agglutination test with the Salmonella serovars indicated the responsiveness of SBY1. SBY1 was reactive only with strains that possessed O19-antigen. The agglutinating ability of SBY1 was absorbed completely with bacilli possessing O19-antigen. These finding indicates that SBY1 is specific for O19-antigen. Polyclonal factor sera for he serotyping of the O3, 10 group of Salmonella cross-reacted with Salmonella group O1, 3, 19 in the slide agglutination test. In contrast, SBY1 did not cross-react with serovars from several other Salmonella groups. These data suggest the usefulness of SBY1 as a serodiagnostic tool for serotyping of Salmonella.

Antibodies, Monoclonal↗
PubMed1990

[O5-antigenic classification of Salmonella typhimurium isolated from outbreaks of Salmonella enteritis].

S. typhimurium (STM) were isolated from outbreaks of Salmonella enteritis and were studied for their reactivity to monoclonal antibody TMY1 specific for Salmonella O5-antigen with the following results; By using the bacterial agglutination test with TMY1, STM were classified into O5-antigenic molecule positive and negative (copenhagen type) strains, suggesting the usefulness of TMY1 as an exquisite epidemiologic tool for Salmonella enteritis.

Antigens, Bacterial↗
PubMed1990

[Production and characterization of a monoclonal antibody specific for Salmonella O5-antigen].

The present report described the production and characterization of a monoclonal antibody, TMY1, specific for an O-antigen of Salmonella bacilli. The following results were obtained: The slide agglutination test against strains of Salmonella serovars indicated the responsiveness of TMY1. TMY1 was reactive only to strains that also possessed O5-antigen in group O4. The agglutinating ability of TMY1 was absorbed completely with bacilli possessing O5-antigen in group O4. When treated with 1 N HCl, bacilli possessing O5-antigen in group O4 showed no agglutinability in the presence of TMY1. The data indicates that TMY1 was specific for O5-antigen. Strains of Salmonella group O4 were classified by the agglutination test with TMY1 into two subgroups, O5-antigen positive and negative, suggesting the usefulness of TMY1 as an epidemiologic tool for the serotyping of Salmonella.

Agglutination Tests↗
PubMed1989

Activation of murine T cells by toxic shock syndrome toxin-1. The toxin-binding structures expressed on murine accessory cells are MHC class II molecules.

Toxic shock syndrome toxin-1 (TSST-1)-binding structures present on murine lymphoid tissues were investigated by using 125I-TSST-1. T-depleted C57BL/6 spleen cells incubated with TSST-1 for 3 h at 0 degree C were mitogenic to splenic T cells, indicating that the former cells bind and present TSST-1 to T cells. TSST-1-binding activity was observed in C57BL/6 splenic B cells and L cells transfected with I-Ab genes, but not in splenic T cells and control L cells. Scatchard plot analysis showed that these B cells and transfectants bound TSST-1 with similar binding affinity. SDS-PAGE analysis showed that lysates of C57BL/6 spleen cells and the I-Ab-positive transfectants contain a single band which bound TSST-1 and comigrated with I-Ab heterodimers. TSST-1-binding activity observed clearly in C57BL/6. BALB/c, and C3H/HeN spleen cells and L cells transfected with I-Ab or I-Ak genes was not reduced by paraformaldehyde fixation. Binding of 125I-TSST-1 to the three spleen cells was markedly reduced by anti-I-A antibodies, but not by anti-I-E antibodies. C57BL/6, C3H/HeN, and (C3H/HeN x C57BL/6) F1 T cells were activated by TSST-1 to proliferate and produce IL-2 in the presence of FT6.2 cells, LT1-30-3 cells and either of them, respectively, but not in the presence of control L cells. These results indicate that I-A molecules function as the structures via that accessory cells directly bind TSST-1 on the cell surface and present a triggering signal of TSST-1 to T cells.

Animals↗
PubMed1989

Possible role of Streptococcus pyogenes in mucocutaneous lymph node syndrome. VIII. Immunological tolerance to S. pyogenes-associated antigens seems essential to induction of MCLS.

In our previous studies, we attempted to show that new-born mice infected with an attenuated strain of Streptococcus pyogenes, and exposed to streptococcal antigens approximately one month later, failed to develop a humoral response to those antigens but were able to respond normally to other unrelated antigens. Since such immunological characteristics are identical to those of patients with the mucocutaneous lymph node syndrome (MCLS), the present studies were performed with the aim of assessing the antibody-forming activities of peripheral blood lymphocytes collected from MCLS patients. These lymphocytes were cultured in the presence of pokeweed mitogen, streptolysin-O and streptococcal C-polysaccharide, leading to their refractoriness to S. pyogenes-associated antigens coupled with normal responsiveness to unrelated antigens. The implication of such immunological responsiveness elicited from neonatal exposure to streptococcal antigens is discussed, particularly with reference to the induction of MCLS.

Antibody Formation↗
PubMed1989

Possible role of Streptococcus pyogenes in mucocutaneous lymph node syndrome. IX. Quantitation by ELISA of streptococcal pyrogenic exotoxin in the serum of MCLS patients.

In the present paper we describe the use of an enzyme-linked immunosorbent assay reinforced with an introduction of monoclonal antibody, for the detection and quantitation of streptococcal pyrogenic exotoxin (SPE) in the serum of patients with mucocutaneous lymph node syndrome (MCLS). The amount of SPE was usually at a high level, and its 100% incidence in patients' sera was proved whenever the assay was made on the day of admission, thereby showing a marked contrast to carefully matched control sera which failed to mediate any positive result. As for the change in detected amount of the toxin, a clear dichotomy was observed between the serum of gammaglobulin-treated patients and that of infants given aspirin; in the former the positive result turned to negative rapidly following the initiation of treatment coupled with a defervescence, while in the latter the reduction of SPE levels was scarcely monitored for as long as 17 days after the onset of illness. Quantitation of SPE might be an auxiliary test for the diagnosis of MCLS, because a considerable amount of SPE was assessed in a patient who developed characteristic huge coronary artery aneurysms following an illness which did not fulfill the diagnostic criteria. These findings support our speculation in relation to the certain role of S. pyogenes as an etiological agent for MCLS. The possible mechanisms of gammaglobulin treatment in reducing the prevalence of cardiovascular lesions and the duration of systemic inflammation are discussed.

Animals↗
PubMed1985

Production of monoclonal antibodies against prostatic acid phosphatase by in vitro immunization of human spleen cells.

Monoclonal antibodies against human prostatic acid phosphatase (PAPase) were produced by immunization of human primary spleen cell cultures. Dissociated spleen cells were cultured for 5-8 days in the presence of 100 ng/ml of PAPase and pokeweed mitogen (1:5000). Following immunization, B cells were isolated and infected with Epstein-Barr virus (EBV). Two weeks after EBV-transformation, cells were fused with either mouse myeloma cells (SP2/OAg14) or human/mouse heteromyeloma cells (SHM-D33). Hybrid clones were screened for anti-PAPase production. In 7 independent immunizations, the average fusion frequency was 3.6 per 10(6) lymphocytes. 18-32% of the hybridomas produced anti-PAPase; approximately 75% of these secreted IgM and 25% secreted IgG. Antibody specificity was determined by immunoassay and immunohistological studies. The procedures described here may be suitable for the production of human monoclonal antibody of a useful specificity.

Acid Phosphatase↗
PubMed1981

Mitogen-induced DNA synthesis in various mouse strains infected with a large or small dose of murine leprosy bacilli.

Mice of the C57BL strain have been shown to be rather resistant to infection with Mycobacterium lepraemurium, whereas C3H mice are highly susceptible. Accordingly, it seemed to be somewhat paradoxical that enhanced antibody formation coupled with a depressed state of cell-mediated immunity as expressed by negative macrophage migration inhibition tests was observed not in C3H but in C57BL mice when they were inoculated with a large dose of murine leprosy bacilli, as reported in our previous studies. In the present study mitogen-induced DNA synthesis by lymph node cells was examined in 16 strains of mice which had been infected with a large or small dose of M. lepraemurium. According to the response to two kinds of T-cell mitogens, these mouse strains could be roughly divided into three groups consisting of two polar groups represented by C57BL/6J and C3H/HeN, respectively, and one intermediate between them. Furthermore, both humoral and cellular immune responses so far observed in C57BL and C3H mice were substantiated by DNA synthesis by lymph node cells harvested from these strains of mice and then exposed in vitro to B-cell and T-cell mitogens, respectively. However, no correlation was found between mitogen-stimulated DNA synthesis by these 16 strains of mice and their H-2 specificity.

Animals↗
PubMed1976

Characterization of background anti-trinitrophenyl plaque-forming cells observed in several strains of mice.

Normal mice have a large number of background anti-trinitrophenyl (TNP) antibody-forming cells (AFC) in their spleens (about 40-50 anti-TNP PFC/10(6) cells). We investigated this among several mouse strains, i.e., C57BL/6, C3H/He, Balb/c, ddd, and ICR mice, and found that all strains had a similar number of anti-TNP PFC (plaque-forming cells). Developmental aspects of background anti-TNP PFC in the ontogenic process were also investigated. The number of anti-TNP PFC increased logari thmically during the first few days of age, reached a peak on the 13th day and attained a constant value within 30 days. Neonatal thymectomy did not decrease the number of background anti-TNP PFC but such treatment decreased the anti-TNP PFC response to TNP-HRBC (horse red blood cells) immunization. Germ-free ICR mice had a number of background anti -TNP PFC similar to that of conventional ICR mice. Avidity of background anti-TNP PFC was compared among mice of several ages and it was shown that there were no differences among them. These results suggest that the occurrence of these background anti-TNP PFC is not elicited by the immune response but by the natural maturation of precursors of ACF without antigenic stimulation.

Animals↗