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S Nonoyama

Publications and source records attributed to S Nonoyama.

At least 55 records · Page 3Linked to original sources
PubMed1995

[Neutropenia in patient with X-linked hyper-IgM syndrome].

The X-linked form of hyper-IgM syndrome (HIGM1) is a rare disorder characterized by the inability of B cells to undergo isotype switch by a deficiency of CD40 ligand (CD40L) on activated T lymphocytes. The patients suffer from recurrent infections not only due to a lack of B lymphocyte activation but also due to defect of T lymphocyte functions. In addition, neutropenia is frequently accompanied by these symptoms. A patient with HIGM1, we experienced, suffered from recurrent infections and neutropenia. But he had a normal number of hematopoietic stem cell by the in vitro colony forming assay. CD34+ myeloid stem cell has been known to express CD40. We speculated by these facts that myeloid cell numbers are regulated by CD40-CD40L interaction.

Adolescent↗
PubMed1994

CD40 ligand expression is defective in a subset of patients with common variable immunodeficiency.

Common variable immunodeficiency (CVI) is characterized by hypogammaglobulinemia and recurrent bacterial infections due to failure of CVI B cells to differentiate in vivo into immunoglobulin-secreting plasma cells. We hypothesized that T-cell dysfunction resulting in abnormal contact-mediated B-cell activation may play a prominent role in the failure of CVI B cells to produce specific antibody. We have previously shown that B-cell proliferation and IgE production after stimulation with anti-CD40 and interleukin (IL) 4 were normal in 22 CVI patients evaluated, indicating that CVI B cells respond to signals delivered via CD40. Here we report that CD40 ligand (gp39) mRNA expression by activated lymphocytes from CVI patients (n = 31) as a group was significantly depressed (P < 0.0001) compared with normal controls (n = 32). gp39 mRNA expression by activated lymphocytes from 13 CVI patients fell below the normal control range. T-cell surface expression of functional gp39 protein was correspondingly low in those patients with gp39 mRNA levels below normal control range and normal in patients with gp39 mRNA levels within normal control range. In CVI patients as a group, gp39 mRNA levels correlated with IL-2 mRNA levels (P < 0.002, r = 0.6) and production (P < 0.001, r = 0.7) but not with gene expression or production of other lymphokines evaluated, suggesting an as-yet-undetermined association between gp39 and IL-2 gene regulation. Of the 13 patients whose activated T cells exhibited gp39 mRNA expression below the normal control range, 2 had normal T-cell-derived lymphokine production, whereas the remaining 11 exhibited broader T-cell dysfunction, resulting in IL-2 deficiency, and in some patients deficient production of other lymphokines as well, reflecting a heterogeneity in the underlying mechanisms leading to depressed gp39 expression in these patients. The observation that both gene and surface expression of gp39 by activated T cells is depressed in a subgroup of CVI patients suggests that inefficient signaling via CD40 may be responsible, in part, for failure of B-cell differentiation in these patients.

Adolescent↗
PubMed1994

Effect of IL-2 on immunoglobulin production by anti-CD40-activated human B cells: synergistic effect with IL-10 and antagonistic effect with IL-4.

Activation of B cells by anti-CD40 provides an excellent model to investigate the direct effect of various cytokines on Ig production. Using this culture system, we examined the effect of IL-2 alone or in combination with other cytokines. IL-2 alone had only a moderate effect on Ig production by anti-CD40-activated B cells if compared with the effect of IL-10. However, IL-2 significantly augmented the synthesis of IgM, IgA, and IgG, including all IgG subclasses by anti-CD40-activated B cells cultured in the presence of IL-10. Both IgD- and IgD+ B cells showed an increase of IL-10-induced Ig production if IL-2 was added to the culture. The addition of IL-2 also increased immunoglobulin synthesis by anti-CD40/IL-10-activated B cells from patients with common variable immunodeficiency (CVI) and defective IL-2 production, suggesting that in a subgroup of CVI patients the IL-2 deficiency may contribute to the observed hypogammaglobulinemia. In contrast, the addition of IL-2 had a suppressive effect on IgE and IgG4 production by B cells cultured in the presence of anti-CD40 and IL-4. These data demonstrate that IL-2 plays an active role in the regulation of Ig production via CD40 by anti-CD40-activated B cells.

Adult↗
PubMed1994

The random inactivation of the X chromosome carrying the defective gene responsible for X-linked hyper IgM syndrome (X-HIM) in female carriers of HIGM1.

The molecular origin of X-linked hyper IgM syndrome has recently been identified as a defect in the ligand of CD40, gp39, a protein expressed on the surface of activated T cells. The availability of detailed pedigrees for three families with affected males allowed assessment of the random or nonrandom nature of the inactivation of the defective X chromosome as well as a determination of the origin of the mutation. X chromosome inactivation was studied because of the relevance to the ability to detect carriers of HIGM1 and the potential for phenotypic effect in the carriers. Using immunostaining, PCR, and DNA sequencing, we found that the defective gene for gp39 is not selectively inactivated. Even in the presence of extremely skewed inactivation, normal levels of serum Ig were found. In carriers in which the defective gene is predominantly expressed, staining alone revealed the carrier status reliably while cloning and sequencing of the cDNA was necessary when the normal gene was predominantly expressed. Unlike some other X-linked defects where extreme Lyonization may lead to disease, a small population of cells expressing the wild-type gp39 is sufficient to maintain normal humoral immunity and prevent the clinical symptoms of X-HIM.

Adolescent↗
PubMed1993

Specific antibody production to a recall or a neoantigen by SCID mice reconstituted with human peripheral blood lymphocytes.

To explore the extent of immune reconstitution of SCID mice by human peripheral blood lymphocytes (hu-PBL-SCID mice), we studied the production of immunoglobulin isotypes and specific antibody (Ab) by the engrafted human cells. Human IgG was detectable in 94% of hu-PBL-SCID mice. IgE synthesis by hu-PBL-SCID mice correlated with the IgE levels observed in human donors. All SCID mice receiving PBL obtained from human donors previously immunized with the T-cell-dependent Ag, bacteriophage phi x 174 (phage), produced phage neutralizing antibody. Quantity and quality (Ig isotypes) of phage-specific Ab produced by hu-PBL-SCID mice correlated with that observed in the donor serum. Human B cells alone failed to engraft, and T cells were required for the production of Ig and anti-phage Ab. Phage-specific Ab production occurred without direct Ag exposure of the hu-PBL-SCID mice, suggesting that the specific Ab production was induced directly by polyclonal activation of the engrafted human cells. Intravenous phage injections given 4 wk after cell transfer failed to further increase the anti-phage Ab titer. Phage neutralizing Ab production could not be boosted if spleen cells obtained from hu-PBL-SCID mice were cultured in the presence of Ag. However, hu-PBL-SCID mice produced increased amounts of anti-phage Ab, providing they were injected with phage at the time of cell transfer. Injection of phage at the time of cell transfer, but not 4 wk later, to mice receiving PBL from nonimmunized donors induced production of minute amounts of anti-phage Ab. We conclude that human peripheral blood lymphocytes transferred into SCID mice become maximally stimulated presumably by xenogeneic murine Ag, resulting in polyclonal expansion of the graft and spontaneous production of Ab to Ag the human donor was previously exposed to, and in loss of responses to subsequent Ag exposure. Ab production to neoantigen, however, can be induced and that to recall Ag can be modified if PBL are exposed to Ag at the time of cell transfer.

Adult↗
PubMed1993

B cell activation via CD40 is required for specific antibody production by antigen-stimulated human B cells.

Costimulatory signals provided by T cells are required for B cells to produce specific antibody (Ab) to T-dependent antigen (Ag) bacteriophage phi x 174. In this study, we demonstrate that if cultured in the presence of anti-CD40, interleukin 10 (IL-10), and Ag, purified B cells can produce antiphage Ab in quantities comparable to those synthesized by B cells cocultured with Ag and T cells. Isotypes produced by B cells in this culture system correspond to those observed in sera of B cell donors. Culture of immunoglobulin (Ig)D- and IgD+ B cells reveals that Ag-induced production of antiphage Ab is restricted to IgD- subset of B cells. In the absence of Ag, anti-CD40/IL-10-stimulated B cells produce only minute amounts of antiphage Ab, indicating that Ag stimulation is indispensable and provides a signal that is synergistic with anti-CD40 and IL-10. Addition of a soluble form of the CD40 ligand (sgp39) to the culture system has a similar effect on specific Ab synthesis as anti-CD40; addition of the soluble construct, CD40 Ig, known to inhibit gp39/CD40 interaction, suppresses in vitro antiphage Ab production by Ag exposed peripheral blood mononuclear cells. Finally, in vivo requirement of gp39/CD40 interaction for specific Ab production was demonstrated by the finding that activated T cells from patients with x-linked hyper IgM syndrome express functionally defective gp39 and respond with depressed Ab titers and fail to switch from IgM to IgG after multiple phage immunizations. These observations illustrate that in vitro and possibly in vivo Ag-specific Ab synthesis requires the presence of Ag and IL-10, and activation signals via CD40.

Antibodies, Viral↗
PubMed1993

Strain-dependent leakiness of mice with severe combined immune deficiency.

Mice with immunodeficiency provide an excellent in vivo model for cell transfer experiments. In this study, we compare the extent of immune deficiency of the original CB17 severe combined immune-deficient (SCID) mice with that of two other strains of immune-deficient mice, the recently developed C3H SCID mice and the beige/nude/X-linked immune-deficient (BNX) mice. Detectable levels of serum lg (higher than 0.4 microgram/ml) were found in 79% of CB17 SCID mice studied (n = 24) and in all BNX mice (n = 12); some leaky CB17 SCID mice had normal levels of Ig. In contrast, only 15% of C3H SCID mice (n = 61) had detectable serum lg; the highest Ig level in this strain was 9.6 micrograms/ml. Age had no effect on serum Ig concentrations of C3H SCID mice; in contrast, all old (> 1-year-old) CB17 SCID mice studied had detectable levels of serum Ig. Transfer of syngeneic, normal, neonatal thymocytes increased serum Ig of SCID mouse origin to near-normal levels in all CB17 SCID mice but had no effect on serum lg concentrations in C3H SCID mice. Treatment with anti-asialo-GM-1 antiserum to abrogate NK cell activity increased serum Ig levels in 37% of CB17 SCID mice but had no effect on Ig production in C3H SCID mice. Flow cytometric analysis failed to identify mature T or B cells in C3H SCID mice; in contrast, some leaky CB17 SCID mice had detectable numbers of T and B cells in the peritoneal cavity. After immunization with bacteriophage phi X 174, neither C3H nor CB17 SCID mice, including leaky mice, produced specific antibody to phage. In contrast, BNX mice produced small but significant amounts of anti-phage antibody. These results indicate that, of the three strains of immune-deficient mice, C3H SCID mice have the most severe immune defect. We predict that C3H SCID mice will be best suited for cell transfer experiments.

Animals↗
PubMed1993

The CD40 ligand, gp39, is defective in activated T cells from patients with X-linked hyper-IgM syndrome.

The prominent role of the CD40 receptor in B cell responses led us to investigate the role of the gp39-CD40 interaction in a group of primary immunodeficient patients with defective antibody production. Here we report that patients with hyper-IgM syndrome (HIM) have a defective gp39-CD40 interaction. B cells from HIM patients express functional CD40, but their T cells do not bind CD40-Ig. These patients expressed normal levels of gp39 mRNA, but these mRNAs encode defective gp39 proteins owing to mutations in the extracellular domain of gp39. Soluble recombinant forms of gp39 containing these mutations were unable to bind CD40 and drive normal B cell proliferation. The gene encoding gp39 was mapped to Xq26, the X chromosome region where the gene responsible for HIM had previously been mapped. These data suggest that a defect in gp39 is the basis of X-linked HIM.

Adolescent↗
PubMed1993

Activated B cells from patients with common variable immunodeficiency proliferate and synthesize immunoglobulin.

Most patients with common variable immunodeficiency (CVI) have normal numbers of circulating B cells but low concentrations of serum Ig. To determine if the hypogammaglobulinemia is caused by an intrinsic B cell defect, we studied B cell function of 22 CVI patients. Cultured B cells from all CVI patients underwent normal proliferation and synthesized normal quantities of IgE in the presence of anti-CD40 and IL-4. If cultured with anti-CD40 and IL-10, four patterns of Ig isotype synthesis were observed. Six CVI patients produced normal amounts of IgM, IgG, and IgA. Four patients produced normal quantities of IgM and IgG. Of the remaining 12 patients who failed to synthesize IgG and IgA, 8 produced normal and 4 synthesized decreased amounts of IgM. Analysis of the IgG subclasses produced by 10 patients with IgG-secreting B cells revealed that IgG4 was the most affected subclass, followed by IgG2; synthesis of IgG3 and IgG1 remained normal. Similarly, in the six IgA producing patients, IgA2 was more often affected than IgA1. The hierarchy of Ig isotype and subclass synthesis corresponds to Ig heavy chain constant region gene location on chromosome 14. Thus, circulating B cells of CVI patients are committed to synthesize one or more Ig isotypes or subclasses, and under proper conditions can proliferate, mature into Ig-secreting cells, and undergo class switch to IgE.

Adolescent↗
PubMed1993

The role of adhesion molecules in the regulation of antibody responses.

We used the T-cell-dependent antigen, bacteriophage (phage) phi X174, to study antibody synthesis in patients, guinea pigs, and dogs with complement component deficiencies (C2, C4, C3, C7); in patients with adhesion molecule deficiencies (CD11/CD18 or sialylated Lewisx); and in patients with the hyper IgM (HIM) syndrome (absence of functional gp39 expression by activated T cells). Patients and guinea pigs deficient in early complement components, patients deficient in CD11/CD18, and patients lacking functional gp39 on activated T cells responded to repeated phage immunizations with depressed antibody titers, lack of or inadequate amplification, and failure to switch from IgM to IgG, suggesting that defective T-cell-B-cell interaction is the cause of the antibody deficiency observed in these patients.

Animals↗
PubMed1993

Regulation of antibody responses: the role of complement and adhesion molecules.

To analyze the importance of cell surface-associated molecules in modulating the immune response by facilitating T/B cell interaction, we used the T cell-dependent antigen, bacteriophage phi X174. Taking advantage of "experiments of nature", we studied specific antibody synthesis in patients with deficiencies of complement components or of the adhesion molecule CD11/CD18 (leukocyte adhesion defect, LAD) and guinea pigs and dogs with early complement component deficiency. Following intravenous injection of bacteriophage phi X174 into normal subjects or animals, a primary response consisting of IgM, a secondary response consisting of IgM and IgG, and a tertiary, predominantly IgG response can be distinguished. Patients and guinea pigs deficient of early complement component and LAD patients responded to repeated phage immunization with depressed antibody titers, lack of or inadequate amplification, and failure to switch from IgM to IgG, suggesting a defect in generating antigen-specific memory cells. Several mechanisms have to be considered: (i) The complement portion of the antigen-antibody complement complex facilitates the accumulation and trapping of antigen in lymphoid organs, thus improving the response to Ag at low concentrations. (ii) Immune complexes preferentially bind to antigen-specific B cells, cells expressing Fc receptors, or CR2 and CR3, the receptors for C3bi. (iii) The weak binding established between the MHC-II/Ag complex and the TCR complex is strengthened through the binding of several adhesion molecule pairs. (iv) Receptor-ligand binding initiates activation signals. The concept of binding/signaling via interacting molecules is further supported by the observation that mAb 60.3, recognizing the beta chain of CD11/CD18, blocks in vitro synthesis of antibody to bacteriophage by primed PBMC.

Animals↗
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↗
PubMed1991

Immunological abnormalities and endothelial cell injury in Kawasaki disease.

Kawasaki disease is an acute febrile disease causing vasculitis, which may lead to as severe a complication as myocardial infarction. This disease is characterized by marked activation of the immune system, including elevation of various cytokines, polyclonal B cell activation, and decrease of CD8+ cells. The high levels of cytokines induce adhesion molecules and a new antigen on endothelial cells. As a result, the immune cells bind to the endothelium and the activated immune cells produce cytotoxic antibodies against the new antigen on the endothelial cells. Thus, the activated immune system is involved in the endothelial cell injury. IVIG (intravenous immunoglobulin) therapy suppresses the activated immune system and reduces the endothelial cell damage.

Coronary Aneurysm↗
PubMed1991

Adherence of Candida albicans to tissues from mice with genetic immunodeficiencies.

Ex vivo adherence comparisons were made between immunocompetent and immunocompromised mouse tissues, and the roles of serum immunoglobulin and macrophages in the adherence of Candida albicans were investigated. Spleen, lymph node, and kidney tissues were harvested from congenitally immunodeficient mice, including AKR/scid, C.B-17, C3Hscid, and N:NIH nu/bg/xid mice, and their normal counterparts into which the defects were bred (AKR/J, C3H/HeSnJ, and BALB/c-ByJ). Tissues were compared for the ability to bind C. albicans 219 in an ex vivo assay. In general, immunodeficiencies significantly decreased binding of C. albicans to spleen but not to lymph node or kidney tissue compared with immunocompetent mice. In C3Hscid and AKRscid mice, spleen tissues from "nonleaky" mice bound significantly fewer yeast cells (P = 0.0005 and 0.0009, respectively) than did those from C3H/HeSnJ or AKR/J mice. Numbers of adherent yeast cells were similar in "leaky" AKRscid and AKR/J mice. Yeast adherence to spleen tissue from N:NIH nu/bg/xid mice correlated with mouse age (P = 0.01). Measurements of total serum immunoglobulin indicated that the scid defect was most complete in C3Hscid mice and that yeast adherence in spleen tissue correlated with immunoglobulin titers. Results of adherence assays and macrophage-specific immunostains suggested that factors determining adherence differ among reticuloendothelial organs.

Animals↗