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101.
Hortense Dodo Damien Marsic Monique Callender Ernst Cebert Olga Viquez 《Food and Agricultural Immunology》2002,14(2):147-154
Peanut is one of the most allergenic foods and reports of accidental ingestion of peanuts in unsuspected food are increasing. No information is available on the allergen content of peanut germplasm grown commercially and used in the food and confectionery industry. The objectives of this study were: (1) to determine the allergen contents of 34 peanut introductions (PI); and (2) to identify naturally occurring allergen-free and/or low or hypoallergenic peanuts germplasm. A basic ELISA protocol was utilized to detect the presence of antigens in the peanut lines using a pool of human sera from patients with documented history of peanut allergy. Two naturally occurring low, or hypo-allergenic germplasm were identified as PI 261942 and PI 338386. Both are Valencia market types with total allergen content significantly lower (P ≤0.05) than that of PI 119880 (0.550), PI 119876 (0.415) and PI 118991 (0.410) three Valencia market types and PI 262111 (0.485), a Virginia market type. No allergen-free PI was found. Allergen content of peanut lines from Bolivia and Paraguay were significantly (P ≤0.05) different to those from Venezuela. No significant difference was observed in the allergen content of the four market types. 相似文献
102.
103.
We have developed a sandwich-type ELISA system for measuring total IgD levels in the serum of atopics and non-atopic controls. In this ELISA system, affinity purified goat anti-human IgD was used for capture. Results were superior to those obtained with monoclonal anti-human IgD antibody. No cross-reactivity could be demonstrated to IgG, IgM, IgA or IgE. The assay showed minimal non-specific binding even with initial serum dilutions of 1:2. The results obtained were reproducible among replicates (Mean CV +/- SEM = 0.03 +/- 0.002; n = 251), between dilutions (CV = 0.08 +/- 0.006; n = 108), and between assays (CV = 0.05 +/- 0.12; n = 5). We used routine radioimmunoassay for measuring total serum IgE. Using these assays total serum IgD and IgE levels were measured in 75 atopic patients and 33 normal subjects. None of the atopics had recent immunotherapy. As expected, the geometric mean serum IgE in atopics (373 ng/ml) was significantly higher than that in normal subjects (49 ng/ml) (P less than 0.01). However, geometric mean serum IgD was also significantly higher in atopics (20.3 micrograms/ml) than that in normal subjects (8.4 micrograms/ml) (P less than 0.02). In both atopic and normal groups, mean serum IgD level did not differ significantly on the bases of age, sex or asthmatic status. Furthermore, total serum IgD was not significantly correlated with total serum IgE (r = 0.14; P = 0.14; n = 108), indicating that immunoregulatory control of the basal levels of the two isotypes is not linked.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
104.
Allergen immunotherapy induces a suppressive memory response mediated by IL-10 in a mouse asthma model 总被引:2,自引:0,他引:2
Vissers JL van Esch BC Hofman GA Kapsenberg ML Weller FR van Oosterhout AJ 《The Journal of allergy and clinical immunology》2004,113(6):235-1210
BACKGROUND: Human studies have demonstrated that allergen immunotherapy induces memory suppressive responses and IL-10 production by allergen-specific T cells. Previously, we established a mouse model in which allergen immunotherapy was effective in the suppression of allergen-induced asthma manifestations. OBJECTIVE: In this study, we examined whether immunotherapy induces a long-lasting effect and investigated the role of IL-10 in successful immunotherapy. METHODS: Ovalbumin-sensitized BALB/c mice were treated with 3 injections of ovalbumin (1 mg, subcutaneous) on alternate days. After a short interval (1 week) and after a long interval (5 weeks), mice were challenged by ovalbumin inhalation, and subsequently, airway reactivity, airway eosinophilia, ovalbumin-specific IgE, and T(H)2 cytokine profile were measured. Flow cytometry and blocking of IL-10 receptors in vivo were used to gain insight in the role of IL-10 in the beneficial effects of allergen immunotherapy. RESULTS: After a long interval between ovalbumin immunotherapy and ovalbumin challenge, the development of airway eosinophilia and hyperresponsiveness to methacholine were as strongly suppressed as after a short interval. These suppressive effects coincided with significantly reduced serum ovalbumin-specific IgE levels and T(H)2 cytokine production. On immunotherapy, the IL-5:IL-10 ratio in the bronchoalveolar lavage fluid shifted toward IL-10. In ovalbumin-restimulated lung cell and thoracic lymph node cultures from these mice, IL-5 levels dramatically decreased, whereas the percentage of IL-10(+)CD4(+) T cells was not affected. Finally, in mice treated with mAb against IL-10 receptors, the beneficial effects of immunotherapy were largely abrogated. CONCLUSION: These data demonstrate that allergen immunotherapy induces a memory suppressive effect in which IL-10 is essential. 相似文献
105.
Summary A formula relating oncotic pressure torat serum protein concentration was derived and found to be in complete agreement with the Landis-Pappenheimer formula derived from measurements onhuman plasma.This study was supported by the Danish Medical Research Council and Johan and Hanne Weimann's legacy. 相似文献
106.
S. Breitner-Ruddock Reinhard Würzner Jörg Schulze V. Brade 《Medical microbiology and immunology》1997,185(4):253-260
Sixteen Borrelia burgdorferi strains, including all three species, were compared in a colorimetric bactericidal assay for their ability to escape the
complement-dependent bacteriolysis on incubation in normal human serum free of specific antibodies (NHS). The species B. afzelii was found to be serum resistant (EB1, EB3, FEM1, FEM2, Pko), whereas strains of the species B. garinii were found to be serum sensitive (1/B29, G1, G2, PSth, PBr, PTrob). Six strains, mainly B. burgdorferi sensu stricto, were only partially sensitive (Z25, 297, B31, PKa-I, PBi). All strains activated the complement cascade in NHS, whereas only
four strains (G1, G2, PBr, PSth) could activate complement in the presence of EGTA-Mg. After complement activation, covalently
bound C3 fragments (C3b, iC3b) were detected on serum-sensitive as well as serum-resistant borrelial strains. Heterogeneity,
however, was observed between serum-resistant and serum-sensitive strains with respect to deposition of C6 and C9. Whereas
serum-sensitive strains were strongly positive for C6 and C9 and were, therefore, killed by the terminal complement complex
(TCC), serum-resistant strains were devoid of C6 and C9 on their cell surface. The serum resistance may, therefore, be due
to an absent or only transient formation of TCC on the bacterial surface.
Received: 17 September 1996 相似文献
107.
Peptides derived from IgE heavy chain constant region induce profound IgE isotype-specific tolerance
Yanyu Wang Robert Schmaltz Fu-Tong Liu Michael W. Robertson Thomas M. Petro Swey-Shen Chen 《European journal of immunology》1996,26(5):1043-1049
(BALB/c × SJL)F1 mice, perinatally injected with peptide-N-glyconase F-treated, deglycosylated IgE heavy chain or recombinant IgE heavy chain (CH?2-CH?4), were profoundly inhibited in antigen-specific IgE production. There exist minimally two tolerogenic IgE peptides, residing in the CH?2 and CH?4 domains. Peptide I, generated by V8 protease, comprises 39 amino acids within CH?2, beginning at amino acid 103. Peptide E begins at amino acid 312 of the CH?4 domain and extends through the CH?4 domain. The total lack of antigen-specific IgE responses in IgE peptide-treated mice was not due to overproduction of interferon-γ, nor lack of interleukin (IL)-4, as predicted by the Th2/IL-4 paradigm for IgE production. IgE-tolerant mice exhibited comparable levels of circulating anti-IgE antibodies to those of PBS-treated control mice. IgG obtained from sera of both sources failed to inhibit IgE responses in vitro. Moreover, IgE responses of spleen cells from IgE peptides-treated mice were restored by CD4+ T cells from PBS-treated control mice. We hypothesize that regulation of antigen-specific IgE responses is mediated by CD4+ T cells which normally recognize IgE peptides on IgE precursor B cells, and can be rendered tolerant by perinatal IgE peptide treatment. 相似文献
108.
JM Hopkin 《Current opinion in immunology》1997,9(6):788-792
Atopy — a T helper 2 cell driven hypersensitivity to innocuous antigens (allergens) which causes most cases of asthma — is of complex genetic and environmental origins. There is compelling epidemiological evidence for a rise in atopic disease in ‘westernised’ communities. The changing pattern of microbial exposure in early childhood is suggested to be the principal candidate mechanism for this rise. 相似文献
109.
110.