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Biomedical subjects

J Yata

Publications and source records attributed to J Yata.

At least 73 records · Page 4Linked to original sources
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↗
PubMed1990

[Anti-CD45R antibody-treated normal lymphocytes respond to interleukin 2 (IL2) after stimulation by allergens].

Interleukin 2 (IL2) responsiveness was specifically induced by Dermatophagoides farinae (Df) antigen in Df-sensitized lymphocytes from asthmatic children, but not in normal lymphocytes. Df-induced IL2 responsiveness was also observed in normal lymphocytes pretreated (Day 0) with anti-CD45R antibody, which recognize suppressor inducer subset among CD4+ T cells. However anti-CD45R antibody was no longer effective when the lymphocytes were cultured for more than one day with the antigen, suggesting its effect in the initial phase of the reaction. The intensity of the response induced in normal lymphocytes by the anti-CD45R was comparable to that of the patients sensitized to the nominal antigen. The response of the patients was no longer augmented by the anti-CD45R antibody. Taken together, these data suggest that even normal lymphocytes have potentiality to elicit Df-induced IL2 responsiveness and it is probably derepressed by inhibiting suppressor inducer subset with the anti-CD45R antibody. Also suggested is a defective suppressor inducer activity in the lymphocytes which may lead to hyperreactivity to allergens in asthmatic children.

Allergens↗
PubMed1989

Fluorescence intensity analysis through simplex optimization in flow cytometry.

Fluorescence intensity analysis in flow cytometric surface immunophenotyping has recently been appreciated in clinical applications. A curve fitting method to estimate the mean and SD values of fluorescence intensity is described in this report. A Gaussian distribution is aimed to be adapted for a specified distribution in logarithmically scaled histogram data through the simplex optimization, one of the non-linear least squares methods. In comparison with the conventional methods which include the detection of peak point and the direct calculation, this fitting method has demonstrated exceeding precisions in the estimation of both parameters with limited involved cell counts in typical lymphocytic phenotyping. The actual estimation for a precise SD value will develop the quality control approaches based on the fluorescence intensity analysis. While this method is not suitable for distributions that involve extremely small cell counts or that deviate markedly from a symmetric Gaussian, it has additional advantages of loose requirements, namely, narrow fitting regions, ordinarily small cell counts, practical computational periods and a simple programming.

Antigens, Surface↗
PubMed1989

Only dull CD3+ thymocytes bind to thymic epithelial cells. The binding is elicited by both CD2/LFA-3 and LFA-1/ICAM-1 interactions.

In view of the necessity for thymocytes to interact with thymic epithelial cells to differentiate into mature T cells, this study analyzed the binding between human thymocytes, cultured thymic epithelial cells (CTEC) and the required adhesion molecules. Immediately after separation, thymic epithelial cells (TEC) readily expressed ICAM-1, which is one of the ligands of LFA-1 cell adhesion molecules. However, the ICAM-1 expression was gradually lost upon culture of TEC. IFN-gamma re-induced ICAM-1 on the CTEC, and the ability of CTEC to bind to thymocytes was also increased by IFN-gamma treatment. The increase in binding seemed to be caused by the LFA-1/ICAM-1 interaction, since it was inhibited by anti-ICAM-1 monoclonal antibody (mAb) and anti-LFA-1 mAb. This suggests that the LFA-1/ICAM-1 interaction is also involved in vivo with the binding of thymocytes to TEC, which have been shown to express ICAM-1. To better understand the nature of the cells involved in binding, thymocytes were sorted into CD3-, CD3dull+, and CD3bright+ subsets (which are supposed to represent the immature, intermediate and mature stages of differentiation, respectively), and were examined for their binding to IFN-gamma-treated CTEC. The result showed that only the CD3dull+ subset bound to CTEC. CD3-, CD3bright+ cells and peripheral blood T lymphocytes did not bind, but they were induced to bind by neuramidase treatment All these bindings were inhibited by anti-LFA-1 mAb and anti-CD2 mAb. These findings indicate that CD3dull+ cells can bind to TEC via CD2/LFA-3 and LFA-1/ICAM-1 interactions. Other cells seemed not to bind to TEC because of sialylation.

Antibodies, Monoclonal↗
PubMed1989

Phenotypical and functional heterogeneity of the large granular lymphocytes increased after various treatments in a patient with combined immunodeficiency.

A boy with combined immunodeficiency having low natural killer (NK)-cell activity received thymopoietin pentapeptide (TP-5) treatment, transplanted with T cell-depleted HLA-haploidentical bone marrow (BMT) cells from his father and with thymus tissue from an infant at different times during the first year of life. He showed a marked increase in large granular lymphocytes (LGL) both during the treatment with TP-5 and after BMT. The LGL generated following TP-5 injection had a T3+Leu11- surface phenotype and low NK activity. In contrast, the LGL appearing after BMT showed T3-, Leu7+, and/or Leu11+ surface phenotypes, had high NK- and K-cell activities, and were lymphokine-activated killer (LAK)-cell precursors. These killer activities were assigned to the Leu7-Leu11+ subset and proved to be of recipient origin. LGL proliferation following BMT was accompanied by neutropenia, which was improved in association with a reduction in the number of LGL and the appearance of T cells of BMT donor origin following thymus transplantation. This suggested the inhibition of granulopoiesis by the LGL and an in vitro study revealed that the Leu7+Leu11- subset of LGL suppressed the growth of granulocyte/macrophage colony-forming units. These results indicated that phenotypically different LGL could be generated by different treatments and that the LGL showing NK activity were distinct from those regulating granulopoiesis. It was also suggested that the generation of LGL was controlled by T cells.

Adjuvants, Immunologic↗
PubMed1989

The role of T cells in immunoglobulin class switching of specific antibody production system in vitro in humans.

Only antibodies of the IgM class were produced in vitro by peripheral blood mononuclear cells stimulated with streptococcal carbohydrate. B cells of the peripheral blood mononuclear cells, however, synthesized both IgM and IgG class antibodies when combined with tonsillar T cells, suggesting that T cells inducing immunoglobulin class switching are present in the tonsils. Peripheral blood T cells also became capable of inducing B cells to produce IgG class antibodies when the T cells were incubated with antigen-pulsed macrophages. Surface IgM-positive, IgG-negative high-density B cells produced IgG antibodies for streptococcal carbohydrate in the presence of these T cells or tonsillar T cells. The culture supernatant solutions from these T cells or tonsillar T cells, however, failed to cause the B cells to produce IgG, indicating that class switching is not mediated by factors released from T cells. Lymphokines such as interleukin-2, human B cell growth factor, helper T cell factor, or interferon-gamma were also incapable of inducing IgG production. These results suggest that the cognate interaction between T cells and B cells is necessary for the immunoglobulin class switching.

Antibodies, Bacterial↗
PubMed1989

Allergen-specific induction of interleukin-2 (IL-2) responsiveness in lymphocytes from children with asthma. I. Antigen specificity and initial events of the induction.

Interleukin-2 (IL-2) responsiveness of Dermatophagoides farinae (Df)-stimulated lymphocytes from children with bronchial asthma was studied. Six-day culture of lymphocytes from allergic patients increased after an additional 3 days of incubation with recombinant IL-2. This phenomenon was not observed when the lymphocytes of patients allergic to Df were stimulated with ovalbumin (OVA). Normal lymphocytes stimulated with Df expressed Tac antigen (low-affinity IL-2 receptor) but, in contrast to the patients' lymphocytes, did not absorb nor respond to IL-2. Nonadherent responder cells cultured with Df-pulsed autologous adherent cells acquired IL-2 responsiveness, but those cultured with OVA-pulsed adherent cells did not. The monoclonal antibody to HLA-DQ framework (Leu 10 and clonab DQ), but not to HLA-DR framework (OKIa1) and HLA-DP (HLA-DP and clonab DP-DR), blocked the antigen-presenting cells from inducing IL-2 responsiveness. Nonadherent responder cells depleted of OKT4 (CD4)-positive cells failed to acquire IL-2 responsiveness, whereas depletion of OKT8 (CD8) cells had no impact. Taken as a whole, the results indicate that DQ-bearing adherent cells from allergic donors play a key role in presenting Df antigen to allergen-specific responder T cells, which are very likely to be members of the OKT4 positive subset.

Absorption↗
PubMed1989

Allergen-specific induction of interleukin-2 (IL-2) responsiveness in lymphocytes from children with asthma. II. Regulation of IL-2 responsiveness by supernatants of normal lymphocytes.

Induction of interleukin-2 (IL-2) responsiveness by Dermatophagoides farinae (Df)-stimulated lymphocytes from children with asthma was markedly suppressed after the addition of culture supernatants from Df-stimulated normal T cells. Ovalbumin (OVA)-induced IL-2 responsiveness of lymphocytes from patients with hen-egg allergy was not suppressed by the supernatant from Df-stimulated T cells, indicating the antigenic specificity of the effect. Patients' lymphocytes whose IL-2 responsiveness was decreased still expressed Tac antigen (low-affinity IL-2 receptors) but, in contrast to the patients' original lymphocytes, did not absorb or respond to IL-2, suggesting the loss of high-affinity IL-2 receptors (p55/p75) from these cells. The supernatant from Df-stimulated normal T cells from one individual did not necessarily suppress the response of all patients tested, indicating the existence of some allogeneic barrier between the factor(s) and patients' lymphocytes.

Absorption↗
PubMed1989

Lymphocytes after autologous and allogenic bone marrow transplantation.

Lymphocyte reconstitution after bone marrow transplantation (BMT) was analyzed using two-color flow-cytometry in 18 patients and the differences between allogenic and autologous BMT were studied. The CD8 (+) CD11b (+) and CD8 (+) Leu7 (+) suppressor subsets were increased while the CD4 (+) 2H4 (+) suppressor inducer subset was decreased in both groups after BMT. These variations of suppressor associated subsets persisted for more than 100 days and were considered to be related to immunologic abnormalities in post-BMT patients. In addition, Ia (+) T cells were increased in both autologous and allogenic BMT patients. This increase appears not to be caused by reaction to allo-antigens, but rather reflects the reconstitution of the lymphocyte system after BMT. In contrast, the CD16 (+) NK cell subset was increased specifically in allogenic BMT patients and only for a short time following transplantation.

Adolescent↗
PubMed1989

Interferon-induced resistance of tumor target cells against lysis by interleukin-2-activated killer cells.

IFN-gamma has been shown to decrease the susceptibility of target cells to NK cell-mediated cytotoxicity. In this report, the effect of IFN-gamma on the sensitivity of target cells to killing by various human lymphocyte cytotoxic activities such as NK/K, IL-2-augmented NK/K cell activity, and IL-2-activated killer activity were studied. Although NK-sensitive K562 cells showed marked resistance to NK cell activity as previously reported, the resistance was overwhelmed by augmentation of NK activity with IL-2. IL-2-activated killer cell activity, which can lyse NK-resistant tumor cell lines upon culture in IL-2, showed decreased cytotoxicity against most of the IFN-gamma-treated target cells tested. By contrast, no decrease of target cell sensitivity to K cells was observed, even though K cells were treated with IL-2. These findings suggest that as far as NK-resistant tumor cells are concerned, an IFN-dependent mechanism inhibits the Fc receptor-independent mediators of tumor surveillance, but not Fc receptor-dependent ones. This should be considered when planning adoptive immunotherapy of IL-2-activated killer cells for human malignancy.

Cytotoxicity, Immunologic↗
PubMed1989

Suppression of in vitro immunoglobulin synthesis by CD16(Leu11a)+ CD56 (NKH1,Leu19)+non-T lineage NK cells; lack of suppression of cells from immunodeficient patients.

We examined the effect of both CD3-CD16(Leul la)+CD56(NKH1,Leu19)+ non-T lineage natural killer (NK) cells and CD3+CD8+CD16-CD56+ T lineage NK cells on B cell proliferation and differentiation. Fluorescence-activated cell sorter (FACS) purified CD16+CD56+ cells suppressed pokeweed mitogen (PWM) induced immunoglobulin synthesis. However, the T lineage NK cells tended to suppress immunoglobulin synthesis only when CD8+ cells were eliminated from the culture, and even then CD16+ NK cells suppressed antibody production more efficiently than did CD3+CD8+ NK cells. CD16+ NK cells did not suppress B cell proliferative responses to several mitogens. CD16+ NK cells from patients with Wiskott-Aldrich syndrome, who showed the high percentage of CD16+ NK cells, did not inhibit immunoglobulin synthesis. We concluded that non-T NK cells are the major immunoregulatory NK cells for immunoglobulin synthesis in normal immune systems, and that they suppress immunoglobulin synthesis through their action on B cell differentiation.

Adult↗
PubMed1989

[In vitro detection of ovalbumin-specific IgA producing cells from lymphocytes of patients with hen-egg allergy].

We studied antigen-specific IgA production from the peripheral lymphocytes of children with hen-egg allergy by using the method of indirect plaque forming cell (PFC) assay. The number of OVA-specific IgA-PFC generated from the patient lymphocytes was low (6 +/- 3/7 X 10(4) non T cells) in comparison with age-matched normal children (112 +/- 18/7 X 10(4) non T cells). The numbers of OVA-specific IgG-PFC and IgM-PFC generated from the patient lymphocytes were not so different from those of the age-matched normal children. This indicates that the activity of OVA-specific IgA-antibody production was reduced in patients with hen-egg allergy.

Child, Preschool↗
PubMed1989

[Thyroglobulin (Tg)-specific induction of IL2 responsiveness in lymphocytes from patients with Hashimoto thyroiditis and its dependency on HLA-DQ antigen].

The peripheral blood mononuclear cells from Hashimoto thyroiditis patients acquired IL2 responsiveness in response to thyroglobulin stimulation, when they were partially depleted of adherent cells. Non-adherent cells reconstituted with Tg-pulsed autologous adherent cells at the ratio of 9:1 also acquired IL2 responsiveness, but those cultured with OVA (ovalbumin)-pulse adherent cells did not. This indicates Tg-induced IL2 responsiveness was specific for the antigen. Although there was no clear correlation between the intensity of induced IL2 responsiveness and the serum titer of anti-Tg antibody, Tg-induced IL2 responsiveness was significant in the seropositive patients. Pretreatment of the mononuclear cells with the monoclonal antibody to the HLA-DQ framework (Leu 10), but not the HLA-DR framework (OKIal), blocked the induction of IL2 responsiveness. This indicated that DQ-bearing adherent cells play a key role in presenting Tg antigen to the responder cells.

Adult↗