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Biomedical subjects

K Onoue

Publications and source records attributed to K Onoue.

At least 19 recordsLinked to original sources

Purification and characterization of the serotype-specific polysaccharide antigen of Trichosporon cutaneum serotype II: a disease-related antigen of Japanese summer-type hypersensitivity pneumonitis.

Summer-type hypersensitivity pneumonitis (SHP) is a unique type of hypersensitivity pneumonitis and the most prevalent in Japan. Our previous study clarified that the causative agent of the disease is Trichosporon cutaneum, and that the patients with SHP have high titres of antibodies against the serotype-specific antigen of polysaccharide nature which exist in the high molecular weight fraction of the culture supernatant of the yeast. In this study, we purified the serotype-specific antigen of serotype II T. cutaneum by gel filtration and affinity chromatography using a monoclonal antibody, D-8, specific for a high molecular weight antigen of serotype II T. cutaneum, and elucidated the structure of the antigen. This affinity-purified antigen was shown to be an essentially acidic polysaccharide comprising mannose, xylose, and glucuronic acid (6:44:4.7). Chemical analysis showed that this polysaccharide antigen contains a (1-3)-linked mannan backbone attached with short side chains of (1-4)-linked mannose and a small proportion of (1-2)-linked xylose residues by substituting the 2- or 4-positions of the (1-3)-linked mannose residues of the main chain. Approximately one-fifth of the side chains were terminated with glucuronic acid residues. The antigenic epitope of the serotype-specific antigen was shown to involve the terminal glucoronic acid residues as revealed by immunodiffusion test and sandwich enzyme-linked immunosorbent assay using monoclonal antibody D-8.

Alveolitis, Extrinsic Allergic↗

The suppressive effect of gelatin-conjugated superoxide dismutase on disease development and severity of collagen-induced arthritis in mice.

We studied the effect of superoxide dismutase (SOD) on murine collagen-induced arthritis (CIA), an animal model of human rheumatoid arthritis (RA). Among SOD derivatives studied, only gelatin-SOD conjugate which has prolonged half life in vivo was effective to suppress the development of CIA, while native SOD or gelatin carrier alone was ineffective. Interestingly, pyran polymer-conjugated SOD which also has a long half life showed no suppressive effect on the disease. No significant effect on immune response against type II collagen (CII) was found in any of the experimental groups. In addition, induction of suppressor cells was not detected in spleen or lymph node cells of the gelatin-SOD-treated group. Therefore, these results suggest that oxygen radicals may have an important role in the effector phase of the immune response to manifest this chronic autoimmune polyarthritis. Thus, the use of appropriate antioxidants for the treatment of human RA may be rationalized.

Animals↗

Analysis of serotype-specific antibodies to Trichosporon cutaneum types I and II in patients with summer-type hypersensitivity pneumonitis with monoclonal antibodies to serotype-related polysaccharide antigens.

Summer-type hypersensitivity pneumonitis is the most prevalent type of hypersensitivity pneumonitis in Japan. We constructed a sandwich enzyme-linked immunosorbent assay system for diagnosis of summer-type hypersensitivity pneumonitis in which monoclonal antibodies were used to bind serotype-related polysaccharides to plastic plates, and this system was proven to have sufficient sensitivity and specificity.

Adolescent↗

A 68-kD GTP-binding protein associated with the T cell receptor complex.

The identity of the guanine nucleotide-binding protein (G protein) involved in T cell activation pathways remains unclear. We identified a 68-kD GTP-binding protein associated with the T cell receptor (TCR)/CD3 complex using immunoprecipitation and GTP-affinity labeling techniques. Proteins coimmunoprecipitated with the TCR/CD3 complex in digitonin lysate of a human leukemic T cell line, MOLT 16, were incubated with alpha-[32P]GTP and irradiated with ultraviolet rays to covalently link the labeled GTP to GTP-binding proteins. They were then analyzed by electrophoresis. The 68-kD protein exhibited nucleotide specificity for GTP-binding and was insensitive to cholera and pertussis toxins. The 68-kD GTP-binding protein could be coimmunoprecipitated with the TCR/CD3 complex but not with other surface molecules such as major histocompatibility complex class I and lymphocyte function associated-1, which do not cause rapid Ca2+ mobilization. These suggest that the 68-kD GTP-binding protein is specifically associated with the TCR/CD3 complex.

Antigens, Differentiation, T-Lymphocyte↗

Interleukin-2 production by primary adult T cell leukemia tumor cells is macrophage dependent.

We have investigated the cellular requirements for IL-2 production by autocrine proliferating tumor cells from four patients with adult T cell leukemia (ATL). Cultures of these ATL cells both produced endogenous IL-2 protein in the absence of added mitogen and proliferated at higher levels when exogenous recombinant IL-2 was added. Depletion of macrophages in the tumor cell cultures resulted in a sharp decline in tumor cell IL-2 production, while re-addition of macrophages reconstituted this response. Macrophage-derived factors including IL-6 and IL-1 also reconstituted IL-2 production in these macrophage depleted cultures. These results raise the possibility that macrophages may play a central role in HTLV-I mediated immortalization of T cells.

Blotting, Northern↗

A device for tracheal tube during CO2 laser irradiation in laryngomicrosurgery.

We devised that the segment of commercially available defensor II tube coming in contact with the vocal cord was concaved. We used this new tube during CO(2) laser irradiation in laryngomicrosurgery. We came to the conclusion that it was much more superior to the conventional tube in safety and resistance of the material to Co(2) laser irradiation and in increase of the operation field.

Journal Article↗

The effect of anti-adhesion molecule antibody on the development of collagen-induced arthritis.

In order to study how inflammatory cells including autoimmune lymphocytes interact with each other to develop collagen-induced arthritis (CIA), we injected monoclonal antibodies against mouse LFA-1 and ICAM-1 into DBA/1 mice immunized with type II collagen (CII). Both antibodies suppressed the development of CIA. These antibodies showed no effect on anti-CII antibody response, although they both significantly suppressed DTH response. It was suggested that anti-adhesion molecule antibodies suppress CIA mainly through their effect on cell-mediated immunity, without affecting humoral immunity under the conditions used.

Animals↗

Accessory function of human glioma cells for the induction of CD3-mediated T cell proliferation: a potential role of glial cells in T cell activation in the central nervous system.

Accessory function of human glial cells for the induction of anti-CD3 antibody-mediated proliferation of T cells was investigated by using seven glioma cell lines. Three of them were found to function as accessory cells and one of them, U118, was used for further analysis. U118 cells showed the cell-contact-mediated accessory function for T cell proliferation. It was found that protein synthesis was required to reveal this function, suggesting that some surface molecules are synthesized and expressed on U118 cells during interaction with T cells to mediate effective signals in T cells. Intercellular adhesion molecule-1 seemed to be one of such inducible molecules and was shown to contribute to effective accessory cell-T cell interaction, but necessity of other molecule(s) was also suggested.

Antigen-Presenting Cells↗

Development of the cell contact-mediated accessory function for T-cell proliferation in a human promyelocytic leukaemia cell line, HL-60, by 1,25-dihydroxyvitamin D3.

A human promyelocytic leukaemia cell line, HL-60 cells, did not show accessory cell (AC) function to potentiate the proliferation of human T cells induced by anti-CD3 antibody coupled to latex beads (alpha T3-L). This was found to be at least due to the inability of HL-60 cells to express certain molecules which are inducible with interferon-gamma (IFN-gamma) on mature monocytes and are necessary for interaction with T cells. HL-60 cells acquired the ability to express such surface molecules by stimulation with IFN-gamma when the cells were pretreated with 1,25-dihydroxyvitamin D3 (Vit D). The effect of Vit D was reversible, that is, the AC function of the HL-60 cells was lost when the cells were cultured in Vit D-free medium for 7 days. It was also found that HL-60 cells treated with IFN-gamma and then with Vit D did not show significant AC function. The flow cytometric analysis showed that the expression of HLA-DR and intercellular adhesion molecule-1 (ICAM-1) was highly increased on HL-60 cells when stimulated with IFN-gamma after treatment with Vit D. The expression of ICAM-1 was also induced with IFN-gamma on untreated cells but in lower amounts. Monoclonal antibodies against ICAM-1 and HLA-DR inhibited the alpha T3-L-induced T-cell proliferation, indicating that these molecules are at least required for contact-mediated AC function. Thus our study revealed that HL-60 cells express cell surface interaction molecules necessary for potentiating the T-cell proliferation through two steps, differentiation with Vit D to mature monocyte-like cells followed by stimulation with IFN-gamma.

Antigen-Presenting Cells↗

Lowered responsiveness of bronchoalveolar lavage T lymphocytes in hypersensitivity pneumonitis.

We previously reported that Trichosporon cutaneum was the major causative antigen of summer-type hypersensitivity pneumonitis (HP) in Japan. In summer-type HP patients, we noticed that the proliferative responses of bronchoalveolar lavage (BAL) lymphocytes to phytohemagglutinin (PHA) and concanavalin A were significantly lower than those of the peripheral blood lymphocytes of the same patients. It was shown in this study that the low response of BAL lymphocytes was due to an intrinsic lowering of the responsiveness of the T cells. Results of the mixed culture experiments, in which the responses to mitogens of BAL and peripheral blood T cells mixed with either alveolar macrophages or blood monocytes were compared, indicated that the decreased proliferative response was due neither to the suppressive effect nor to defects in accessory function of the alveolar macrophages. BAL T cells did not act as suppressor cells when they were added to the culture of peripheral T cells. The decreased proliferative response was not due to the dominance of CD8+ T cells frequently seen in BAL cells of HP patients, because both CD4+ and CD8+ T cells separated from BAL cells of HP patients showed lower responsiveness than those of peripheral blood T cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Structural differences among guinea pig Fc gamma 1/gamma 2 receptors on macrophages, polymorphonuclear cells, and lymphocytes.

Using the cDNA, D-3, coding for Fc gamma 1/gamma 2 receptor of guinea pig macrophages that binds IgG1 and IgG2 (Fc gamma 1/gamma 2R), we examined the cell distribution of this receptor by RNA blot analysis. The Fc gamma 1/gamma 2R mRNA was expressed in polymorphonuclear cells and B cells as well as in macrophages, but not at the detectable level in T cells. The cDNA amplified from RNA of polymorphonuclear cells in the polymerase chain reaction was the same as D-3. The cDNA of B cells was found to have about 140 bp cDNA segment inserted to the cytoplasmic tail of D-3. We found that the cDNA amplified from T cell RNA differed in signal peptide and extracellular domain sequence from cDNAs of other cell types. This cDNA does not seem to be amplified from the mRNAs of contaminating other cell types.

Animals↗

The structure and expression of the guinea pig Fc receptor for IgG1 and IgG2 (Fc gamma 1/gamma 2R).

A cDNA clone encoding the receptor for guinea pig immunoglobulin G was isolated from a guinea pig peritoneal macrophage cDNA library. The cloned cDNA encoded 271 amino acids containing an N-terminal signal sequence. The deduced amino acid sequence is most homologous to murine Fc gamma RII beta 2. The receptor protein could be expressed in COS-7 and L cells transfected with the cDNA, suggesting that the expression of this receptor does not require the co-expression of a second chain such as gamma chain of Fc epsilon RI or CD3 zeta chain. The transformant L cells showed the binding to both the guinea pig IgG1 and IgG2 antibodies complexed with antigen, indicating that the cDNA we cloned was the one for guinea pig Fc gamma 1/gamma 2R.

Amino Acid Sequence↗

Serotype-related antigen of Trichosporon cutaneum in the induction of summer-type hypersensitivity pneumonitis: correlation between serotype of inhalation challenge-positive antigen and that of the isolates from patients' homes.

Inhalation challenge with the culture filtrate-antigens prepared from two strains of different serotype of Trichosporon cutaneum (TIMM 1573, serotype I; TIMM 1318, serotype II) was performed on patients with summer-type hypersensitivity pneumonitis and asymptomatic seropositive family members. Of the 17 patients, 12 were strongly positive, four were mildly so, and one was negative. Interestingly, of the 16 inhalation challenge-positive patients, four reacted to both serotypes I and II, five to serotype I only, and seven to serotype II only. There was a good correlation between the serotype inhalation challenge-positive antigen and that of T. cutaneum isolated from the homes of two patients' homes. A strain of T. cutaneum demonstrating a new serotype was isolated from the homes of two patients, one of whom was negative to both serotypes I and II. Specific antibody activity, lymphocyte proliferative response, and skin reaction to the antigens were also positive, but these findings were not useful to discriminate the inhalation challenge-positive from the inhalation challenge-negative antigen. Neither of the two asymptomatic family members responded. These results indicate that inhalation challenge in patients with summer-type hypersensitivity pneumonitis is provoked by the serotype-related antigen of T. cutaneum, reflecting the sensitization of these patients in their homes.

Alveolitis, Extrinsic Allergic↗

Stability of IL-2 mRNA in T lymphocytes is controlled by a protein kinase C-regulated mechanism.

The rate of the degradation of interleukin 2 (IL-2) mRNA produced in stimulated human tonsillar lymphocytes was found to be significantly decreased in cells continuously stimulated with a calcium ionophore, A23187, and a phorbol ester, phorbol 12, 13-dibutylate (PDB) as compared with that in unstimulated cells. When the lymphocytes were stimulated with A23187 and PDB, IL-2 mRNA reached a maximum level at 8 h and gradually decreased to almost the base line by 27 h. IL-2 mRNA produced was rapidly degraded when the stimulants were washed out at 12 h and the cells further cultured in the presence of actinomycin D, which stops mRNA synthesis. However, the stability of IL-2 mRNA was increased by the addition of PDB or A23187. A maximal effect was observed when both were added. The effect of PDB was dose-dependent and inhibited by the inhibitors of protein kinase C (PKC), staurosporine, and K252a, suggesting the involvement of PKC in the control of IL-2 mRNA stability. The involvement of protein phosphorylation in the regulating mechanism of IL-2 mRNA stability was supported by the fact that the addition of okadaic acid, which inhibits serine/threonine protein phosphatases, resulted in an increase in the stability of IL-2 mRNA. Further study demonstrated that the rate of degradation of 32P-labeled IL-2 mRNA, which was prepared by cell-free transcription of IL-2 cDNA, in the polysomal fraction obtained from PDB-stimulated lymphocytes was decreased compared with that obtained from unstimulated lymphocytes. These results indicate the presence of a mechanism controlling the stability of IL-2 mRNA that is regulated by PKC.

Calcimycin↗

Different types of antigen-presenting cells affect the induction of experimental autoimmune arthritis.

We obtained a type II collagen-specific murine T cell line containing at least two T cell clones, one reacting with only native collagen II and the other with both denatured and native molecules. Only the former could induce arthritis. The arthritogenic T cell clone(s) was preferentially stimulated to grow when epidermal cells were used as antigen-presenting cells. Conversely, the non-arthritogenic T cell clone(s) was mainly stimulated when spleen cells were used. Thus, it is speculated that different types of antigen-presenting cells preferentially present different epitopes on the same antigen, affecting the resulting in vivo immune phenomena.

Animals↗

Importance of serotype-related antigen in the induction of experimental hypersensitivity pneumonitis by Trichosporon cutaneum in rabbits. Correlation between granulomatous alveolitis and cellular and humoral immune responses to polysaccharide-rich antigen.

We evaluated the immunopathogenic properties of Trichosporon cutaneum, a major etiologic agent of Japanese summer-type hypersensitivity pneumonitis (HP). When the culture filtrate antigen of T. cutaneum was chromatographed on DEAE-cellulose, two peaks of polysaccharide, fractions A and B, were obtained. Fraction B was highly reactive to the specific IgG and IgA antibodies in the serum and bronchoalveolar lavage fluid samples obtained from sensitized rabbits, whereas fraction A was mainly reactive to the IgG antibodies. When the rabbits sensitized by intratracheal injection with the particulate antigen of T. cutaneum were challenged intratracheally by these antigenic fractions, fraction B induced granulomatous alveolitis, but fraction A induced alveolitis rather than granuloma. Lymphocytes of the mediastinal lymph nodes responded prominently to fraction B, but less to fraction A, as assessed by proliferative response. Each of the fractions B obtained from two strains of different serotypes (TIMM 1573, serotype I and TIMM 1318, serotype II) was reactive in enzyme-linked immunosorbent assay to the serum samples from the rabbits sensitized with homologous antigen, but far less to that from the rabbits sensitized with heterologous antigen, that is, the antigenic specificity of fraction B was related to the serotype of T. cutaneum. Fractionation by gel filtration on Sepharose CL-4B revealed that the molecular weight of the antigenic components in fraction B was larger than 1,000,000 and that the components consisted mainly of polysaccharide.(ABSTRACT TRUNCATED AT 250 WORDS)

Alveolitis, Extrinsic Allergic↗