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Biomedical subjects

J Yata

Publications and source records attributed to J Yata.

At least 19 recordsLinked to original sources
PubMed1992

Measurement of beta 2 microglobulin in dried urine spotted on filter paper by means of a forward sandwich enzyme-linked immunosorbent assay.

We devised a highly sensitive forward sandwich enzyme-linked immunosorbent assay (ELISA) for estimation of the beta 2-microglobulin concentration in dried urine spotted on filter paper. This method is suitable for mass screening because of the good reproducibility, satisfactory stability, low operation cost and easy sample collection. However, preliminary studies using our new method for detecting renal diseases in the Tokyo infant population did not produce good results. The high cut-off value may have been the main reason. To make this ELISA more suitable for mass screening, we plan to reduce the cut-off value, test older children and improve the extraction step.

Enzyme-Linked Immunosorbent Assay↗
PubMed1992

CD4+ CD45RA+ T cells modulate allergen-induced interleukin 2 responsiveness in human lymphocytes.

Peripheral blood lymphocytes from nonallergic individuals acquired responsiveness to interleukin 2 (IL2) after stimulation with ovalbumin (OVA) or Dermatophagoides farinae (Df) antigens when they were pretreated with the CD45RA antibody, which has been shown to define the suppressor inducer subset of CD4+ cells and also to block its suppressor activity. The effect provided by the CD45RA antibody was lost if the lymphocytes had initially been activated with the OVA of Df antigens. The magnitude of the responses was comparable to the allergen-induced responses observed in OVA- or Df-sensitized lymphocytes from allergic patients. The pre-existing IL2 responsiveness in the patients was not increased by the CD45RA antibody pretreatment. However, the CD45RA antibody pretreatment gave rise to Df-induced IL2 responsiveness in the lymphocytes of the patients sensitized with OVA but not with Df; conversely, OVA-induced IL2 responsiveness was enhanced in Df- but not in OVA-sensitized lymphocytes. The CD45RA antibody apparently acts on CD4+ T cells, but not on CD8+ T cells, to induce the IL2 response. A further dissection of normal CD4+ T cells indicated that CD4+45RA- T cells preferentially respond to IL2 after stimulation with OVA or Df antigens. Since normal CD4+45RA+ T cells did not show antigen-induced IL2 responsiveness even after pretreatment with the CD45RA antibody, it is unlikely that the CD45RA antibody stimulates CD4+45RA+ T cells to become responsive to IL2 after antigenic challenge. Alternatively, CD4+45RA+ T cells may modulate the activity of CD4+45RA- T cells, which are potentially responsive to IL2 by antigenic stimulation and thus provide tolerance in nonallergic lymphocytes. Collectively, a defective suppressor activity of CD4+45RA+ T cells may exist in patients with hen-egg allergy and/or bronchial asthma, which may cause lymphocytes to be hyperreactive to OVA or Df antigens.

Adult↗
PubMed1992

Characterization of human thymic lymphocytes forming rosettes with stromal cells.

The interaction of thymic lymphocytes and stromal cells is believed to be important for T cell development in thymus. In this study, thymic rosettes (TR), which are cell-cell complexes of thymic lymphocytes and stromal cells, were isolated from human thymic tissue, and were characterized. Treating human thymus with collagenase in mild condition, human TR were successfully isolated. Subsequently, TR were purified by the 1G sedimentation method. Human TR consisted of a stromal cell in center surrounded by lymphocytes. The stromal cells were positive for CD14, CD11b, and HLA-DR but negative for thymic epithelial cell specific mAb, UH-1, suggesting that they are macrophage/dendritic cells. The lymphocytes which formed TR (TRL) were mainly double positive (CD4+CD8+) and CD1+ cells, and few of them expressed bright CD3, indicating that TRL are in the intermediate maturation stage. TRL expressed activation markers (Ta1 and HLA-DR) in a significantly higher percentage of cells than did unselected thymocytes. Blocking test revealed that CD11a and CD2 are involved in the binding of TRL and the stromal cells as adhesion molecules.

Antigens, Surface↗
PubMed1992

[Cytokine therapy of immunodeficiency].

The cellular immunodeficiency diseases especially those with impaired IL-2 production are successfully treated by every day injection of rhIL-2. IL-2 is also effective on some patients with antibody deficiency probably caused by the lack of T cell help for B cells. Prolonged infection of EB-virus, human immunodeficiency virus, fungi and mycobacteria can be ameliorated by IL-2 treatment. Superoxide production and bacteriocidal activity of the leukocytes from some cases of chronic granulomatous disease are improved by injection of interferon gamma. Succeeding injection of G-CSF is effective to maintain the leukocyte count of congenital neutropenia to the level competent to protect bacterial infections.

Agammaglobulinemia↗
PubMed1992

Peroxidase-negative and myelomonocytic antigen-positive acute leukemia.

Between 1983-1988 bone marrow samples obtained from 195 peroxidase-negative leukemia patients were analyzed for their surface antigens. Thirteen of these patients (6.7%) had myelomonocytic-positive and lymphoid-negative antigens. These leukemic cells reacted with CD13 in eight patients, CD33 in seven, CD11 in six and CDw41 in two. In none of these patients did the leukemic cells react with CD1, CD2, CD3, CD4, CD5, CD8, CD10, CD19 or CD20. Leukemic cells from two patients were reactive with CD7. These leukemic cells demonstrated L2 morphology in 11 patients and L1 morphology in one patient. The leukemic cells from the final patient were diagnosed as those of leukemic transformation of myelodysplastic syndrome. Chromosomal abnormality was observed in approximately half of the patients examined (6/10). Cytochemical analysis revealed that the leukemic cells were negative for periodic acid Schiff stain but positive for acid phosphatase. The prognosis of these patients was markedly poor as compared to acute lymphocytic leukemia or typical peroxidase-positive nonlymphocytic leukemia. Complete remission was induced in only 30% of patients and duration of survival was short (4.7 months). This suggests that myelomonocytic antigen-positive peroxidase-negative acute leukemia is a distinct type of leukemia and may require more aggressive therapy to improve survival.

Acid Phosphatase↗
PubMed1992

Reversible G1 arrest induced by dimethyl sulfoxide in human lymphoid cell lines: kinetics of the arrest and expression of the cell cycle marker proliferating cell nuclear antigen in Raji cells.

In order to elucidate further the mechanism of reversible cell cycle arrest induced by treatment of Raji cells with 1.5% dimethyl sulfoxide (DMSO), we have performed a detailed analysis of the kinetics of arrest and of reentry into the cell cycle after removal of DMSO and have correlated cell cycle progression with expression of proliferating cell nuclear antigen (PCNA). No significant effect of DMSO on cell cycle patterns, assessed by flow cytometric analysis of bromodeoxyuridine-prelabeled cells, was seen for the first 19 h of treatment. A clear reduction of entry into S phase was detected by about 25 h of treatment; essentially all cells were arrested with a G1 content of DNA after 96 h of treatment. When DMSO-arrested cells were released from the block, entry into S phase began at 12 h after release and continued in a fairly asynchronous manner for a further 12-14 h. In arrested cells, the content of PCNA was reduced to about 25% of the amount present in logarithmically growing G1 phase cells. Six h after release from DMSO, PCNA RNA transcripts were first detected by Northern blotting. The increase of PCNA protein, detected by Western blotting, was seen by 9 h after release. The kinetics of entry into the cell cycle and restoration of PCNA protein are similar to that seen in serum stimulation of quiescent cells. These results suggest that DMSO reversibly arrests proliferation of Raji cells at G0 or at an early point in G1 phase and that progression through late G1 phase and entry into S phase are correlated with synthesis of the PCNA gene product.

Antigens, Neoplasm↗
PubMed1991

Effect of recombinant interleukin 5 on the generation of cytotoxic T cells (CTL).

The effect of recombinant human interleukin 5 (rhIL5) on the generation of CTL was investigated by using autologous EBV-transformed B cells as the target. Exogenous IL5 augmented the CTL generation, and its effect was most active at the concentration of 10 ng/ml, and when added at the late phase of culture in this system. IL5 augmented specific CTL activity rather than MHC nonrestricted CTL activity as detected with K562 and Daudi when compared to that augmented by IL2. IL5 did not increase the expression of p55 or p75 IL2R nor the responsiveness to IL2. Taken together with the finding that IL5 augmented the CTL activity even in the presence of cyclosporin A, the effect of IL5 on the CTL generation seems not to act through the IL2-IL2R system.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1991

Increase of ovalbumin (OVA)-specific B cells in the peripheral blood of egg-allergic patients.

Allergen-specific B cells were detected by antigen-coated magnetic beads. The frequency of ovalbumin (OVA)-specific B cells was significantly higher in patients with egg white-allergy than in age-matched nonallergic individuals. These B cells, isolated by the immunomagnetic-beads method, produced anti-OVA antibodies of mostly IgM class when they were transformed by Epstein-Barr virus and cultured for about 2 weeks. Based on a chronologic analysis, the increase of OVA-specific B cells was found to precede the increase of IgG and IgE anti-OVA antibodies in the serum. These observations indicated that OVA-binding B cells in the peripheral blood are already committed to producing IgM antibody and probably are the precursors of antibody-forming cells of the IgG or IgE class.

Adult↗
PubMed1991

A B cell line from a patient with pure red cell aplasia produces an immunoglobulin that suppresses erythropoiesis.

A 4-year-old boy with pure red cell aplasia was investigated. Immunophenotypic analysis of peripheral blood lymphocytes revealed a marked increase of CD20+ cells, which fell from 25.9% in the active stage to 9.7% in remission. The plasma contained a suppressive activity against CFU-e and BFU-e formation by the patient's bone marrow cells, which disappeared when the disease went into remission. Prednisone (2 mg/kg/day) therapy was tried for 5 weeks, but produced no improvement. Subsequently, high-dose gamma-globulin therapy induced complete remission of anemia. A lymphoblastoid B cell line obtained from the patient before therapy produced a factor that suppressed erythropoiesis but not granulopoiesis. The suppressive activity resided in the immunoglobulin fraction and was adsorbed by an anti-immunoglobulin column. These results indicate that expansion of B cells producing an immunoglobulin which suppressed erythropoiesis was involved in the pathogenesis of the disease in this patient.

B-Lymphocytes↗
PubMed1991

Generation and function of gamma delta T cells after allogeneic bone marrow transplantation in humans: comparison in absence or presence of HLA-matched or mismatched thymus.

We have observed two patients who exhibited an exclusive increase of delta TCS1+ subset of gamma delta T cells in the peripheral blood after bone marrow transplantation (BMT). In one case with severe combined immunodeficiency (SCID) who received haploidentical BMT from his father, gamma delta T cells appeared only after thymus transplantation. However, his T cell-mediated immunity remained severely defective despite the generation of T cells of donor origin. In the other case with aplastic anemia, delta TCS1- gamma delta T cells began to increase in the peripheral blood later. This indicates that the thymus is necessary for the generation of gamma delta T cells and that the delta TCS1+ subset is dominant in the early stages of their ontogeny. delta TCS1+ T cell lines were established from both patients, and allo-reactivity was investigated. The cell line from the latter case reacted to recipient cells in a mixed lymphocyte reaction, but did not show cytotoxity to the allogeneic cells including recipient cells. The other cell line, from the former case, did not react to either donor or recipient cells. This indicates that an intact thymus is needed for gamma delta T cells to acquire allo-reactivity. Both cell lines showed MHC non-restricted cytotoxity against NK-sensitive target cells.

Adolescent↗
PubMed1990

Phenotypic profile and functions of T cell receptor-gamma delta-bearing cells from patients with primary immunodeficiency syndrome.

TCR-gamma delta-bearing T cells have been reported to be increased in several immunodeficient patients. However, their functional role and phenotypic characterization have not yet been well documented. In this study we examined the surface phenotypes and functional properties of TCR-gamma delta+ cells from several patients with primary immunodeficiency syndrome. It was demonstrated that TCR-gamma delta+ cells detected by TCR-delta 1 mAb were increased in some of the patients, particularly in patients with Wiskott-Aldrich syndrome and severe combined immune deficiency. The TCR-gamma delta+ cells showed such a unique profile that more than 60% of the cells expressed delta-TCS1, which is normally present in a lesser amount, and that most of the cells lacked CD5 T lineage marker. TCR-gamma delta+ cells from the patients with primary immunodeficiency syndrome served as NK cells as observed in normal individuals, while displaying weak LAK and allogeneic cell-specific killer activities. The TCR-gamma delta+ cells were classified into several subpopulations according to their antigenic phenotype, then their NK activity of normal individuals and patients, lymphokine-activated killer and allo-specific killer activities of normal individuals were compared among the subpopulations. Delta-TCS1+ cells mediated almost the same killer activities as total TCR-gamma delta+ cells, whereas CD8+ TCR-gamma delta+ cells displayed stronger cytotoxic activities in both normal subjects and the patients with primary immunodeficiency syndrome.

Antibodies, Monoclonal↗
PubMed1990

Identification of a cord blood T cell subset of CD3+4-8-45R+ suppressing interleukin 2 production in the autologous mixed lymphocyte reaction and the mode of action of exogenous IL2 in the induction of IL2 production.

As previously reported, the inability of cord blood T cells to produce IL2 in the autologous mixed lymphocyte reaction (AMLR) could be recovered by the treatment of stimulator non-T cells with interferon-gamma (IFN-gamma) and of the AMLR with exogenous IL2. In the present study, we showed that addition of untreated autologous cord blood T cells to the above-mentioned AMLR abrogated the IL2 production in a dose-dependent manner, suggesting active suppression by the untreated T cells because untreated cord blood T cells did not consume IL2. Suppressor activity was abrogated by the treatment of cord blood T cells with monoclonal anti-CD3 antibody plus complement or with monoclonal anti-CD45R (Leu 18) antibody, but not by the treatment with monoclonal anti-CD4 antibody and/or anti-CD8 antibody plus complement. These data showed that the cord blood suppressor T cells were CD3+4-8-45R+. This suppressor activity also disappeared by culturing with rIL2 for 8 hr. As the frequency of CD45R+ cord blood T cells was comparable to that of CD45R+ adult T cells and was minimally affected by the IL2 treatment, functional modulation of CD45R+ suppressor T cells by IL2 is suggested. Moreover, in spite of the inhibitory effect of anti-CD45R antibody on the suppressor activity, IL2 production was not induced merely by addition of anti-CD45R antibody directly to the responder cells in AMLR. Taken together, these data suggest the requirement of exogenous IL2 for IL2 production in that IL2-producing-precursor T cells themselves should be stimulated by IL2 in addition to the modulation of CD45R+ suppressor T cells by IL2.

Adult↗
PubMed1990

Effect of ketotifen on antigen-induced interleukin 2 (IL-2) responsiveness in lymphocytes from patients with atopic dermatitis and/or bronchial asthma.

We tested the effect of Ketotifen (4-(1-methyl-4-piperidylidene)-4H- benzo[4,5] cyclohepta[1,2-b]thiophen-10(9H)-one hydrogen (fumarate) on the induction of allergen-induced IL-2 responsiveness in lymphocytes from patients with atopic dermatitis and/or bronchial asthma. Ovalbumin (OVA)- and/or Dermatophagoides farinae(Df)-induced IL-2 responsiveness was increased in almost all patients (1-15 years old) before Ketotifen treatment. Two to 12 months administration of Ketotifen (0.06 mg/kg/day) decreased activity of the response in 7 out of 9 cases corresponding to improvement of clinical symptoms. In in-vitro studies, antigen presenting cells (adherent cells) from the patient pretreated with 5, 50 and 500 ng/ml doses of Ketotifen for 12 h failed to present OVA or Df antigen to T-cells for induction of IL-2 responsiveness. Antigen-pulsed adherent cells also failed to induce the response of the T-cells pretreated with 50 and 500 ng/ml doses of Ketotifen but not with a 5 ng/ml dose. A 50 ng/ml dose of Ketotifen did not affect T-cells for induction of the response. In contrast, the treated adherent cells are capable of presenting PPD antigen or Con A for the induced response. The combined data indicate that induction of IL-2 responsiveness of peripheral blood lymphocytes on stimulation with nominal antigen may reflect an immune response to allergen in patients with allergy and a weak immunosuppressive effect of Ketotifen seems to block the response in the pathogenic process of allergic diseases.

Adolescent↗
PubMed1990

Changes of several adrenal delta 4-steroids measured by HPLC-UV spectrometry in neonatal patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency.

We have developed an easy and rapid method of reverse-phase high-performance liquid chromatography (HPLC)-UV spectrometry for measuring adrenal delta 4-steroids. Three female neonates with adrenal 21-hydroxylase deficiency (2 salt-losers and 1 simple virilizer), two of whom were recalled by neonatal mass-screening for congenital adrenal hyperplasia (CAH), were diagnosed using this method. Changes of several adrenal steroids were examined in these patients before and after treatment with hydrocortisone. Before treatment, the cortisone and cortisol peaks were very low and those of 17 alpha-hydroxyprogesterone (17-OHP) and 21-deoxycortisol (21-DOF) were high in all 3 patients (17-OHP: 79.9-997 nmol/l, 21-DOF: 83.7-324 nmol/l). The androstenedione peak was also high in 2 of them. A peak produced by 21-deoxycortisone, which is a product of oxidation of 21-DOF at the C-11 position, was also detected in all cases (14.5-297 nmol/l). After treatment, all of these abnormally elevated delta 4-steroids decreased or disappeared. This new method is thought to be valuable for the rapid diagnosis of CAH, and especially for use in neonatal mass-screening for CAH.

17-Hydroxycorticosteroids↗
PubMed1990

Decreased production and responsiveness of interleukin 2 in lymphocytes of patients with nephrotic syndrome.

Production of and responsiveness to interleukin 2 (IL-2) were evaluated in lymphocytes from 18 patients with nephrotic syndrome. The IL-2 production of T cells, when stimulated with autologous non-T cells separated on a polystyrene resin column, was significantly decreased in patients with minimal-change nephrotic syndrome. No significant difference in the level of IL-2 production was noted between minimal-change nephrotic syndrome patients in the nephrotic stage and those in remission. The IL-2 production was also significantly decreased in lymphocytes from patients with membranous nephropathy. The responsiveness to IL-2 was inconstant among patients with nephrotic syndrome. These results indicate that the immune system of regulating IL-2 production is impaired in patients with nephrotic syndrome.

Adolescent↗
PubMed1990

Ovalbumin-specific induction of IL2 responsiveness in lymphocytes from patients with hen egg allergy and its regulation by the culture supernatant of normal lymphocytes.

Interleukin 2 (IL2) responsiveness of ovalbumin (OVA)-stimulated lymphocytes from patients with hen-egg allergy was studied. The number of viable cells of 5-day cultured lymphocytes stimulated with OVA was increased by an additional three days incubation with recombinant IL2. This phenomenon was not observed when the lymphocytes of patients allergic to OVA but not to Dermatophagoides farinae extract antigen (Df) were stimulated with Df. Normal lymphocytes stimulated with OVA expressed Tac antigen (low affinity IL2 receptor) but, in contrast to those from the allergic patients, did not absorb nor respond to IL2. The induction of OVA-specific IL2 responsiveness in patient lymphocytes was markedly suppressed on the addition of culture supernatant from OVA-stimulated normal T cells, but Df-specific IL2 responsiveness of the lymphocytes from Df-sensitized patients with bronchial asthma was not suppressed by the same supernatant. The supernatant of lymphocytes from allergic patients did not show such suppressive effect. The patient lymphocytes whose IL2 responsiveness was suppressed with the supernatant from normal lymphocytes still expressed Tac antigen. These observations suggest that the culture supernatant of normal T lymphocytes stimulated with OVA contained an antigen-specific factor suppressing the induction of IL2 responsiveness of OVA-stimulated patient lymphocytes. The production of such a suppressive factor was impaired in the patient, and further, the factor may have inhibited the triggering signal of IL2 receptors having absorbed IL2. The existence of some allogeneic barrier between the factor(s) and patient lymphocytes was suggested, since the supernatant from OVA-stimulated normal T cells did not necessarily suppress the response of all patients tested.

Absorption↗