• 제목/요약/키워드: Antibody Response

검색결과 619건 처리시간 0.031초

Mechanisms of immune tolerance to allergens in children

  • Kucuksezer, Umut C.;Ozdemir, Cevdet;Akdis, Mubeccel;Akdis, Cezmi A.
    • Clinical and Experimental Pediatrics
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    • 제56권12호
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    • pp.505-513
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    • 2013
  • Because the prevalence of allergic diseases has significantly increased in recent years, understanding the causes and mechanisms of these disorders is of high importance, and intense investigations are ongoing. Current knowledge pinpoints immune tolerance mechanisms as indispensable for healthy immune response to allergens in daily life. It is evident that development and maintenance of allergen-specific T cell tolerance is of vital importance for a healthy immune response to allergens. Such tolerance can be gained spontaneously by dose-dependent exposures to allergens in nature or by allergen-specific immunotherapy. Allergen-specific immunotherapy induces regulatory T cells with the capacity to secrete interleukin-10 and transforming growth factor-${\beta}$, limits activation of effector cells of allergic inflammation (such as mast cells and basophils), and switches antibody isotype from IgE to the noninflammatory type IgG4. Although allergen-specific immunotherapy is the only method of tolerance induction in allergic individuals, several factors, such as long duration of treatment, compliance problems, and life-threatening side effects, have limited widespread applicability of this immunomodulatory treatment. To overcome these limitations, current research focuses on the introduction of allergens in more efficient and safer ways. Defining the endotypes and phenotypes of allergic diseases might provide the ability to select ideal patients, and novel biomarkers might ensure new custom-tailored therapy modalities.

Bioluminescence Single-Site Immunometric Assay for Methamphetamine Using the Photoprotein Aequorin as a Label

  • Kim, Hyun-Sook;Paeng, Insook-Rhee
    • Bulletin of the Korean Chemical Society
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    • 제27권3호
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    • pp.407-412
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    • 2006
  • Bioluminescence single-site immunometric assay for methamphetamine (MA) using the native aequorin, a photoprotein, as a signal generator was developed for the first time. MA is a potent sympathomimetic amine with stimulant effects on the central nervous system. MA abuse induces hallucinations and, thus, may cause a serious social problem. The single-site immunometric MA assay was optimized and its dose-response behavior was examined. The dose-response curve shows that the detection limit is 1.1 ${\times}$ $10^{-10}$ M and a dynamic range is four orders of magnitude with 15 $\mu$g/mL BSA-MA conjugate and 1.0 ${\times}$ $10^{-8}$ M anti-MA antibody-biotin conjugate. In order to evaluate this assay, the structurally similar compounds, amphetamine, ephedrine, norephedrine, benzphetamine and N-4-(aminobutyl)methamphetamine were examined for their crossreactivity. None of these five compounds showed any cross-reactivity. Additionally, an artificial urine solution spiked with MA was analyzed by the MA assay, and the result of the analysis demonstrated the usefulness of the present assay for the determination of MA in urine.

Bordetella bronchiseptica 백신항원의 면역원성 평가 (Evaluation of the immunogenicity of Bordetella bronchiseptica, a vaccine antigen)

  • 우수한;문선영;변윤영;주홍구
    • 대한수의학회지
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    • 제54권2호
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    • pp.75-79
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    • 2014
  • Bordetella (B.) bronchiseptica is a causative agent of swine atrophic rhinitis that promotes colonization of the mucous membrane of the swine nasal cavity by Pasteurella (P.) multocida. Mixed infection with B. bronchiseptica and P. multocida leads to growth inhibition of pigs, resulting in significant economic loss. There are many commercial vaccines for atrophic rhinitis, including B. bronchiseptica as a killed vaccine antigen (Ag). However, the immunogenicity of killed B. bronchiseptica Ag has not yet been elucidated; therefore, this study was conducted to investigate the immunogenicity of killed B. bronchiseptica Ag and the type of immune response it induces. In vitro assays using mouse spleen cells and flow cytometry revealed that B. bronchiseptica Ag induced high proliferation capability of lymphocytes, especially B lymphocytes, and the proliferating cells showed a significant response to interleukin (IL)-2. B. bronchiseptica Ag also enhanced the production of IL-12, a representative cytokine for cell-mediated immunity. In vivo experiments using mice showed that the injection of B. bronchiseptica Ag markedly induced Ag-specific antibody. Taken together, these results indicate that B. bronchiseptica Ag has high immunogenicity by itself.

Effect of Naked Neck Gene on Immune Competence, Serum Biochemical and Carcass Traits in Chickens under a Tropical Climate

  • Rajkumar, U.;Reddy, B.L.N.;Rajaravindra, K.S.;Niranjan, M.;Bhattacharya, T.K.;Chatterjee, R.N.;Panda, A.K.;Reddy, M.R.;Sharma, R.P.
    • Asian-Australasian Journal of Animal Sciences
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    • 제23권7호
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    • pp.867-872
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    • 2010
  • A comprehensive study was undertaken to evaluate the effect of naked neck (Na) gene on immune competence, serum biochemical parameters and carcass quality traits in three genotypes (NaNa, Nana and nana) of the naked neck chicken under a tropical climate (Southern India). Sixty day-old chicks (20 from each genotype) were selected randomly and reared under similar environmental conditions up to eight weeks of age. The cell mediated immune (CMI) response to phytohaemoagglutinin-P (PHA-P) was significantly higher ($p{\lgq}0.01$) in NaNa and Nana genotypes compared to nana birds. The humoral response as measured by antibody titre to sheep red blood cells (SRBC) was also significantly higher in NaNa. The total cholesterol, LDL and VLDL cholesterol levels were significantly ($p{\leq}0.01$) lower whereas HDL cholesterol level was significantly higher in NaNa and Nana compared to nana genotype. The presence of Na allele significantly increased the live weight and dressing yield, and decreased the feather cover and abdominal fat. The naked neck genotypes (NaNa/Nana) performed better than the normal (nana) siblings for almost all the traits studied.

Immunomodulatory effect of Tinospora cordifolia and Centella asiatica and its modulation on cyclophosphamide challenge

  • Siddiqui, NA;Ali, Mohd;Singh, Shobhna
    • Advances in Traditional Medicine
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    • 제8권4호
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    • pp.380-385
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    • 2008
  • Ethanolic extracts of T. cordifolia and C. asiatica were evaluated for immunostimulatory effect in mice against sheep RBCs as antigen by three models viz. delayed type hypersensitivity reaction, ercent change in neutrophil count and haemagglutination titre. Immunostimulatory effect in the presence of immunosuppressant agent, cyclophosphamide (100 mg/kg, i.p.) was also investigated. T. cordifolia and C. asiatica significantly (p < 0.001, p < 0.05 respectively) enhanced foot pad thickness when measured after 24 hours of sheep RBC antigen challenge. Both the plant materials increased foot pad thickness even after being subjected to immunosuppressant exposure. T. cordifolia revealed enhanced neutrophil counts, while C. asiatica had no significant effect on neutrophil counts. T. cordifolia exhibited significantly (P < 0.01) elevated neutrophil levels even in the presence of cyclophosphamide administration. Both the plants exhibited humoral antibody response, as haemagglutination titre values were significantly high as compared to control. T. cordifolia and C. asiatica could combat immunosuppressant effect of cyclophosphamide (P < 0.01). This suggests that T. cordifolia and C. asiatica can be regarded as biological response modifiers and can be utilized for the development of immunostimulating agent among plant sources.

Tumor-associated autoantibodies as diagnostic and prognostic biomarkers

  • Heo, Chang-Kyu;Bahk, Young Yil;Cho, Eun-Wie
    • BMB Reports
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    • 제45권12호
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    • pp.677-685
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    • 2012
  • In the process of tumorigenesis, normal cells are remodeled to cancer cells and protein expression patterns are changed to those of tumor cells. A newly formed tumor microenvironment elicits the immune system and, as a result, a humoral immune response takes place. Although the tumor antigens are undetectable in sera at the early stage of tumorigenesis, the nature of an antibody amplification response to antigens makes tumor-associated autoantibodies as promising early biomarkers in cancer diagnosis. Moreover, the recent development of proteomic techniques that make neo-epitopes of tumor-associated autoantigens discovered concomitantly has opened a new area of 'immuno-proteomics', which presents tumor-associated autoantibody signatures and confers information to redefine the process of tumorigenesis. In this article, the strategies recently used to identify and validate serum autoantibodies are outlined and tumor-associated antigens suggested until now as diagnostic/prognostic biomarkers in various tumor types are reviewed. Also, the meaning of autoantibody signatures and their clinical utility in personalized medicine are discussed.

Immunosuppressive Characteristics of Oligomycin Derivatives Produced by Streptomyces lydicus MCY-524

  • Lee, Sang-Yong;Han, Sang-Bae;Kim, Hang-Sub;Kim, Young-Ho;Kim, Hwan-Mook;Kim, Chang-Jin;Hong, Soon-Duck;Lee, Jung-Joon
    • Journal of Microbiology and Biotechnology
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    • 제7권1호
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    • pp.56-61
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    • 1997
  • A strain producing immunosuppressive substances was isolated from a soil in Cheju island. By morphological, cultural, and physiological studies, the strain was identified as Streptomyces lydicus MCY-524. Cultured broth was purified by silica gel, sephadex LH-20 and preparative HPLC and gave two immunosuppressive compounds, MCH-22 and MCH-32. They dramatically suppressed the B cell activation with lipopolysaccharide, T cell activation by mixed lymphocyte response, and primary T-dependent antibody response at a final concentration of 1 ${\mu}g$/ml. They also markedly suppressed the proliferation of lymphocytes induced by lipopolysaccharide, pokeweed mitogen, and concanavaline A at the same concentration. Their suppressive activities, which were comparable to those of cyclosporin A, suggested that they were potent and broad immunotoxic agents on the immune functions of murine lymphocytes.

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Early Growth Response-1 Plays a Non-redundant Role in the Differentiation of B Cells into Plasma Cells

  • Oh, Yeon-Kyung;Jang, Eunkyeong;Paik, Doo-Jin;Youn, Jeehee
    • IMMUNE NETWORK
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    • 제15권3호
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    • pp.161-166
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    • 2015
  • Early growth response (Egr)-1 is a $Cys_2-His_2-type$ zincfinger transcription factor. It has been shown to induce survival and proliferation of immature and mature B cells, respectively, but its role in the differentiation of B cells into plasma cells remains unclear. To examine the effects of Egr-1 deficiency on the activation of B cells, naive B cells from $Egr1^{-/-}$mice and their wild-type (WT) littermates were activated to proliferate and differentiate, and then assayed by FACS. Proportions of cells undergoing proliferation and apoptosis did not differ between $Egr1^{-/-}$ and WT mice. However, $Egr1^{-/-}$ B cells gave rise to fewer plasma cells than WT B cells. Consistently, $Egr1^{-/-}$ mice produced significantly lower titer of antigen-specific IgG than their WT littermates upon immunization. Our results demonstrate that Egr-1 participates in the differentiation program of B cells into plasma cells, while it is dispensable for the proliferation and survival of mature B cells.

자외선에 의한 면역반응의 억제를 회복시키는 면역조절물질을 생산하는 토양 Streptomyces sp.의 분리 및 동정 (Isolation And Identification Of Soil Streptomyces sp. Producing An Immunomodulator That Restores Ultraviolet B Radiation-Induced Suppression Of The Immune Response)

  • 모영근;신영근;박동진;김창진;이종길;한성순
    • 약학회지
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    • 제39권6호
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    • pp.585-592
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    • 1995
  • Soil microorganisms producing immunomoduators that can restore ultraviolet B (UVB) radiation-induced suppression of the immune response were screened in vitro. Exposure of freshly isolated murine epidermal cells (EC) to $180{\;}J/m^{2}$ of UVB radiation resulted in approximately 90% impairtnent of accessory cell function, as measured by their ability to support anti-CD3 monoclonal antibody-induced T-cell mitogenesis. When the culture supenmtants of 150 actinomycete strains were exanuned for their capacity to prevent or repair the UVB-induced impairment of accessory cell function, 4 of them were identified to contain immunomodulators that can restore the decreased accessory cell finiction. The soil isolate that showed the most effective restorative activity, G40025. was selected and fturther characters Addition of 10.mu.l of the culture supernatant of G40025 grown in G-media to cultures of UVB-irradiated EC right after UVB-irradiation restored the decreased accessory cell function by 58%. The immunomodtdator produced by G40025 appeared to be stable at 100.deg. C for 10 min. Taxonomical studies by cultural, morphological, and physiological characterization showed that the soil isolate, G40025, belongs to the genus Streptomyces.

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Homogeneous Enzyme-Linked Binding Assay Mediated by the Interaction of Avidin with Biotin: Mistletoe Lectin I Assay

  • Rhee Paeng, In-Suk;Lee, Eun-Ah;Kim, Hyun-Sook
    • Bulletin of the Korean Chemical Society
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    • 제25권1호
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    • pp.115-118
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    • 2004
  • We have examined the feasibility of using the specific interaction between mistletoe lectin I (ML I) and ${\beta}$-Dgalactose instead of the anti-ML I antibody in developing a homogeneous type competitive binding assay for ML I. We also have examined the feasibility of adapting the biotin/avidin mediated homogeneous assay for this system. Alkaline phosphatase (AKP) was employed as a single substrate enzyme label. The dose-response curve shows a detection range of 1-25 ${\mu}$g/mL and a linear response with a correlation coefficient of 0.99. To demonstrate the analytical utility of this method, 10 ${\mu}$g/mL of ML I was spiked into distilled water. The results show that the mean recovery was 10.03 ${\mu}$g/mL with an SD of 0.18. The difference between the spiked value and the mean recovery was 0.03 ${\mu}$g/mL, with a relative error of 0.3 and 1.6 % of RSD.