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101.
Three different monoclonal antibodies (MAb) against human immunoglobulin E have been obtained which specifically bind to human myeloma and polyclonal IgE. The antibodies showed high avidities for soluble IgE (0.7 X 10(9) to 3.3 X 10(9) M-1). These MAb defined three distinct epitopes on IgE. A mixture of these antibodies in combination with an 125I-labelled anti-mouse Kappa chain MAb has been used to measure allergen-specific IgE. This determination was performed by a solid-phase radioimmunoassay using allergen extracts coated to either chemically activated paper discs or to polyvinyl chloride wells. This method is 4-10 times more sensitive than other previously reported procedures. A similar technique has also been applied to detect individual allergens in immunoblots of allergen extracts.  相似文献   
102.
Chromosome investigations were carried out in 7 patients with Fanconi's anemia, type Estren-Dameshek. The frequency and types of chromosome instability found in cultured lymphocytes were in accord with those detected in individuals with classical Fanconi's anemia. The break-point distribution indicates a significant excess of breaks in chromosomes No. 1, 2, and 7 and a deficit in No. 18 and X and Y chromosomes. There was a clear clustering of breaks at certain locations in chromosomes No. 1, 2, 3, 7, 9, and 14. The location of the breaks with respect to the bands demonstrated an almost exclusive involvement of the lighter bands, regardless of the banding method used. These results suggest that most breaks take place in the interbands between the G and R bands. In all patients, chromosome instability was less frequent in direct bone marrow preparations than in lymphocyte cultures. However, cultured bone marrow cells showed a significant increase of chromosome aberrations. On the whole, the chromosome data derived from this series of patients are in agreement with those obtained in individuals with classical Fanconi's anemia and give no support to the idea of cytogenetic heterogeneity between subjects affected by these two forms of childhood aplastic anemia.  相似文献   
103.
Comparative nasal absorption of allergens in atopic and nonatopic subjects.   总被引:3,自引:0,他引:3  
Based on sensitization following intranasal antigen administration, previous investigations have suggested greater absorption of allergens through the nasal mucous membranes of atopic than of nonatopic subjects. In this study mucosal absorption was assessed more directly by determining the capacity of allergens applied intranasally to elicit cutaneous Prausnitz-Küstner (P-K) reactions in nonatopic persons as compared with asymptomatic atopic subjects sensitive to other allergens. Two series of reaginic human serum dilutions were injected intracutaneously in recipients backs, and 48 hours later one series was challenged intracutaneously with test allergen. After the responses had been recorded, concentrated allergenic extract was sprayed into the nose and the second series of P-K sites observed for reactivity. Sometimes these P-K sites were rechallenged intracutaneously the following day to determine passive transfer neutralization. Two allergens were studied: bovine ribonuclease (RNase) and peanut extract. Two sera containing peanut reagins and one with RNase antibodies were each used in 10 to 11 atopic and 9 to 11 nonatopic recipients. The atopic group failed to show greater or more rapid absorption of either allergen through the nose based on the highest serum dilution reacting after nasal challenge. the speed of the reaction, the ratio of the titer by nasal challenge to the intracutaneous titer, or passive transfer neutralization. Controls showed that the results were not influenced by systemic absorption of allergen employed for intracutaneous tests. Drinking the amount of peanut extract applied intranasally did not elicit P-K reactions.  相似文献   
104.
Introduction: Fungal diseases are a threat to human health. Therapies targeting the fungus continue to lead to disappointing results. Strategies targeting the host response represent unexplored opportunities for innovative treatments. To do so rationally requires the identification and neat delineation of critical mechanistic pathways that underpin human antifungal immunity. The study of humans with single-gene defects of the immune system, i.e. inborn errors of immunity (IEIs), provides a foundation for these paradigms.

Areas covered: A systematic literature search in PubMed, Scopus, and abstracts of international congresses was performed to review the history of genetic resistance/susceptibility to fungi and identify IEIs associated with fungal diseases. Immunologic mechanisms from relevant IEIs were integrated with current definitions and understandings of mycoses to establish a framework to map out critical immunobiological pathways of human antifungal immunity.

Expert opinion: Specific immune responses non-redundantly govern susceptibility to their corresponding mycoses. Defining these molecular pathways will guide the development of host-directed immunotherapies that precisely target distinct fungal diseases. These findings will pave the way for novel strategies in the treatment of these devastating infections.  相似文献   

105.
H H Higa  G N Rogers  J C Paulson 《Virology》1985,144(1):279-282
This report examines the ability of three sialic acids (SA), N-acetylneuraminic acid (NeuAc), N-glycollylneuraminic acid (NeuGc), and 9-O-acetyl-N-acetylneuraminic acid (9-O-Ac-NeuAc), to serve as receptor determinants for 18 human and animal influenza type A viruses. Viruses were compared by agglutination of receptor-modified erythrocytes containing either the Sa alpha 2,6Gal or the SA alpha 2,3Gal linkages with each of the three sialic acids. Individual isolates differed markedly in their ability to agglutinate cells containing NeuAc, NeuGc, and 9-O-Ac-NeuAc. The results suggest that recognition of the various sialic acids is an important factor in analysis of the receptor specificity of influenza virus hemagglutinins.  相似文献   
106.
Human (T,G)-AL specific T cell helper factors secreted by in vitro activated peripheral blood lymphocytes of normal donors were characterized. Factors were passed through columns of Sepharose coupled either to antibodies against human immunoglobulin or antibodies against the variable region of the heavy (Vh) and light (Vl) chains of human immunoglobulin. In addition, the same factors were applied to columns of Sepharose coupled to anti-HLA-DR antibodies or to monoclonal antibodies against human Ia or β2-microglobulin. The activity of the antigen specific factors was removed by the anti-Vh antibodies and not by anti-Vl or anti-human immunoglobulin antibodies. The factors passed through Sepharose coupled to anti-DR antibodies could be removed and eluted from columns of anti-DR antibodies relevant to the donors' DR antigens. The same factors were also removed by a monoclonal antibody (anti-Ia) which recognizes a monomorphic determinant on HLA-DR, but not by monoclonal anti-β2-microglobulin. The results suggest that the genetically regulated (T,G)-AL specific helper factors possess HLA-DR as well as Vh determinants in their active moiety.  相似文献   
107.
The distribution of HLA antigen frequencies has been studied in patients with affective disorders. There were no significant differences between bipolar patients, unipolar patients, or controls. Preliminary data on HLA antigen distribution in schizophrenic patients are reported. Our negative results in affective disorders are discussed in relation to HLA studies reported from other laboratories, with special reference to some potential methodological problems.  相似文献   
108.
U. Wahn    U. Herold    K. Danielsen  H. Løwenstein 《Allergy》1982,37(5):335-343
In order to determine the allergenic activity of five purified horse allergens, 22 children allergic to horses according to history, skin test, and leukocyte histamine release were evaluated. Washed leukocytes from all patients were tested for allergen-induced histamine release utilizing four epidermal horse allergens (Ags 6, 9, 11 , and 15) and horse serum albumin. Crossed radioimmunoelectrophoresis was carried out with a standardized horse dander extract and serum from each patient.
The results showed considerable variation in the individual allergoprints. Ag 11 had the highest mean allergenic activity. Sensitivity to horse serum albumin was demonstrated three times. Our data show that the amount of serum IgE antibodies bound by horse allergens correlates significantly with the capacity of the allergens to induce histamine release from washed leukocytes.  相似文献   
109.
Growth of diploid cells from breast cancers   总被引:1,自引:0,他引:1  
Cell cultures were derived from normal and cancerous breast tissues and from metastases by methods that selected for relatively adherent epithelial aggregates. Karyotypic analyses of first or second passage cultures yielded predominantly normal diploid cells. Nonclonal aberrations were more common in tumor-derived than in normal cultures. Three of the cultures that originated from metastases were characterized by abnormal clones. These results support observations based on DNA content, which indicate that a considerable fraction of breast cancers are composed predominantly of diploid cells. They differ greatly from chromosomal findings in long-term cultures of tumor effusions and thus emphasize the karyotypic diversity that can be found in tumors from a single tissue of origin--the breast.  相似文献   
110.
Inhaled trimellitic anhydride (TMA) reacts with airway proteins to produce trimellityl (TM) proteins. The TM-proteins result in both systemic and local immune responses, of which various proteins present in the airway can be used for markers. Thus TM-human serum albumin (HSA), TM-IgG, and TM-IgA can be used as hapten-protein complexes for immunologic studies in sera of humans exposed to TMA by inhalation. Various immunologic assays have been established to measure antibodies against TM-proteins and have various purposes. With TM-HSA as a model antigen, total serum antibody may be measured by the ammonium sulfate technique of coprecipitation of TM-125I HSA. By solid-phase radioimmunoassays, IgE, IgG, IgA, and IgM antibodies can be measured. Lymphocyte reactivity can be measured by 3H thymidine uptake of TM-protein-stimulated lymphocytes. Biologic effects of IgE antibody can be measured by allergy skin tests and leukocyte histamine release with TM-proteins such as TM-HSA. The reaction of TMA with proteins results in alteration of those proteins that include changes in charge and physical conformation, the latter resulting in an apparent change in molecular size. These changes may relate to the observations that human antibody is not merely directed against the hapten in the hapten-human protein complex but also against new antigenic determinants formed by the TM-protein complex. Correlations have been made with certain human immunologic responses and lung disease after TMA inhalation, as follows: IgE antibody against TM-proteins correlates with TMA-induced rhinitis, conjunctivitis, and asthma; high levels of total antibody, IgG, and IgA antibody appear to correlate with the late respiratory systemic syndrome, probably a variant of hypersensitivity pneumonitis; workers exposed to TMA fumes (rather than TMA powder) have the highest levels of antibody, and this may correlate with occurrence of the hemorrhagic pneumonitis seen in this group of workers; patients with no symptoms or mild irritative symptoms have the lowest or no antibody levels. The immunopathogenetic relationships may be better understood with the further development of animal models of TMA lung disease now available.  相似文献   
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