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71.
Insolubilized anithyroglobulin antibodies: properties and interest in the study of thyroglobulin 总被引:1,自引:0,他引:1
J Torresani 《Journal of immunological methods》1973,3(1):35-52
Antithyroglobulin antibodies have been insolubilized, either through polymerization of the immune serum by ethyl chloroformate or through covalent binding to cyanogen bromide activated Sepharose 2B. These immunosorbents are able to bind thyroglobulin specifically, however, they have lost a part of the immune serum antibody activity. Thyroglobulin immunosorption is reversible. The degree of reversibility increases respectively with a pH 2 buffer, 3 M NaSCN and 0.1% sodium dodecylsulfate. After desorption by the first two procedures, thyroglobulin remains entirely precipitable by homologous antibodies, however, it undergoes conformational changes, some of them being partially reversible (unfolding of the 19S species, dissociation into 12S subunits). These immunosorbents may be used, under the conditions described, in the quantitative estimation and purification of thyroglobulin. 相似文献
72.
The structuring of an allergy index based on IgE-mediated skin sensitivity to common environmental allergens 总被引:1,自引:0,他引:1
L R Freidhoff D G Marsh D A Meyers R Hussain 《The Journal of allergy and clinical immunology》1983,72(3):274-287
We computed skin-test sensitivity levels in 485 adults puncture-tested with eight standardized, high-quality inhalant allergens tested at single concentrations. In order to quantitate the "average" IgE-mediated skin sensitivity of each subject, we used both nonparametric and parametric statistical methods to generate two "allergy indices" (Allergy Index I and Allergy Index II) based on sensitivity end-point data from the subpopulations of individuals positive to six of the eight allergens. For the 192 skin test-positive subjects, Allergy Index I and Allergy Index II were significantly correlated with each other (rs = 0.98, p less than 0.001) and with the number of positive skin-test reactions (rs congruent to 0.9, p less than 0.001) as well as with log[total serum IgE] (r congruent to 0.4, p less than 0.01). In 102 ragweed-positive subjects, log[specific IgE to ragweed] was significantly correlated with ragweed-specific "ragweed indices I and II" (r congruent to 0.6, p less than 0.01). Furthermore, the average daily symptom scores reported by 14 ragweed-positive subjects during the ragweed pollination season were significantly correlated with ragweed indices I and II (p less than 0.05). We propose the use of Allergy Index II in epidemiologic and genetic studies of allergic phenotypes as well as in clinical decisions for diagnosis and immunotherapeutic intervention. 相似文献
73.
Induction of immunoglobulin-secreting cells from human peripheral blood lymphocytes in a serum-free culture medium was studied. Albumin, transferrin, insulin and fibronectin can replace serum entirely for support of pokeweed mitogen (PWM)-stimulated B lymphocytes, measured by a reverse hemolytic plaque assay using protein A-coated red cells. In this serum-free system, growth and maturation to IgM and IgG secretion occur at the same or higher efficiency as in conventional serum-containing medium, with maximum numbers of plaque-forming cells on day 6 at optimal dose of PWM, 0.5 ~ 5 μg/ml. This system can be used to avoid the interference from undefined serum components. 相似文献
74.
Conjugation of DNA fragments to protein carriers by glutaraldehyde: immunogenicity of oligonucleotide-hemocyanin conjugates 总被引:1,自引:0,他引:1
The practical realization of the concept of specific immunotherapy for systemic lupus erythematosus (SLE) has been hampered, thus far, by an inability to link DNA fragments to carrier protein. In this paper, a novel technique is described, in which glutaraldehyde is the linking agent. A 2-stage method was used to link oligonucleotides to a soluble protein carrier, such as keyhole limpet hemocyanin (KLH) or human gamma globulin (HGG), whereas a 1-stage technique was sufficient to link oligonucleotides to sheep red cells. Both the ultraviolet absorbance spectrum and diphenylamine assay demonstrated that oligonucleotides were coupled to soluble protein. The conjugate of oligonucleotide to protein carrier appears to be recognized by anti-DNA antibody since oligonucleotide linked to either KLH or HGG inhibited the binding of anti-DNA antibody in vitro, and oligonucleotide-coupled sheep cells are agglutinating by seropositve sera from lupus patients. In addition, oligonucleotide-KLH raised hemagglutinating antibody to denatured DNA in C57BL/6, DBA/2 or NZB mice, as well as IgG antibody as detected by SPRIA in C57BL/6 and DBA/2 mice. The significance of this new method for the development of an antigen specific therapy of SLE is discussed. 相似文献
75.
血管内皮损伤标志物在2型糖尿病患者中的变化 总被引:2,自引:1,他引:2
目的:探讨2型糖尿病(DM)患者血管内皮损伤标志物的变化。方法:分别测定89例2型DM患者和76例正常对照者血浆可溶性血管内皮细胞蛋白C受体(sEPCR),血管性血友病因子(v WF)和可溶性血栓调节蛋白(sTM),并测定DM患者24h尿白蛋白排泄(UAE),根据尿UAE水平和病程分组进行比较分析。结果:2型DM患者血浆sEPCR、v WF及sTM水平高于正常对照组(P<0.05),并且与其尿UAE水平和病程呈显著正相关。结论:血浆sEPCR、v WF及sTM水平可作为观察2型DM并发血管病变以及严重程度的指标。 相似文献
76.
The molecular nature of the membrane antigen that is acquired from FCS-containing media by human lymphoblastoid cells has been investigated. The presence of bovine α2, macroglobulin on the surface of Namalva cells was demonstrated by radioimmunoassay using specific antisera. Alternatively, cell-bound bovine α2,M could be detected by the more sensitive heterophile rosette assay described previously. Namalva cells grown in NHS-containing media acquired bovine α2 M upon subsequent incubation with the purified protein in a dose- and time-dependent way. Acquisition of α2 M was demonstrated using both viable and formaldehyde-fixed cells. Purified fetuin, which carries a heterophile epitope shared with bovine α2 M as well as with other glycoproteins, failed to bind with the membrane of Namalva cells. The possible role of acquired α2 macroglobulin on cells has been discussed. 相似文献
77.
M. J. Dascombe 《Progress in neurobiology》1985,25(4):327-373
The ability to minimise, if not prevent, large variations in deep body temperature that would otherwise result from some environmental conditions is a homeostatic function of unquestioned benefit that is demonstrated only by the more highly evolved animals. Nevertheless, body temperature is raised above normal values in many pathological conditions. This increase in temperature or fever is an active and co-ordinated response, which indicates the involvement of the CNS. Central injection and lesion studies have shown that the brain, in particular the PO/AH, is the site of action of fever-inducing agents, termed pyrogens. Electrophysiological data show that pyrogens modify the activity of central thermosensitive neurones as if to increase heat gain and decrease heat loss. The common response of fever to pyrogens of diverse origins is attributable to fever being mediated by an endogenous pyrogen released by phagocytic cells in the host. The mechanism by which central neuronal function is disturbed by pyrogens present in the periphery is not known. Tracer studies have yet to demonstrate the passage of a pyrogen across the blood-brain barrier. The possible involvement of several putative neuro- transmitters and modulators in fever has been reviewed here, but most compounds have not been studied sufficiently to allow firm conclusions to be drawn. Much of the data is limited to the effects of the putative mediators on normal thermoregulation but, even when the effect is hyperthermia, such observations do not necessarily indicate a role for the endogenous material in fever. Dose-response curves for agonists and the effects of antagonists are often undetermined. This shortfall in data is due to some extent to the nature of fever; a central response in vivo over several hours. Although fever may enhance other host reactions to combat infection and inflammation, neither this benefit nor the undesirability of antipyretic therapy has been demonstrated unequivocally in either homeothermic laboratory animals or humans. Consequently, antipyretic drugs continue to be used clinically to alleviate the fever, malaise and/or pain commonly associated with disease. The drugs in common usage are the nonsteroidal antipyretic analgesics, many of which also have an anti-flammatory effect. The primary mode of action of these drugs as antipyretics appears at present to be the inhibition of cyclo-oxygenase and a consequent reduction of prostanoid material in pyrogen-sensitive areas of the brain. PGEs in the PO/AH have received most study to date, but other mediators in other parts of the CNS, where the density of pyrogen receptors may be sparse, cannot be discounted and await further investigation. 相似文献
78.
目的探讨中枢神经系统感染患儿血脑屏障(blood-brain barrier,BBB)与脑脊液(cerebrospinal-fluid,CSF)白蛋白指数的变化。方法采用溴甲酚绿法和免疫比浊法检测18例化脓性脑膜炎患儿急性期、恢复期及22例病毒性脑炎患儿急性期血清和CSF中白蛋白水平,并计算出CSF白蛋白指数。与正常对照组比较。结果化脓性脑膜炎、病毒性脑炎患儿急性期CSF白蛋白、CSF白蛋白指数显著高于正常对照组(P〈0.001),且化脑组显著高于病脑组(P〈0.001)。化脑组恢复期患儿CSF白蛋白、CSF白蛋白指数与对照组无明显差异(P〉0.05)。结论监测CSF白蛋白和CSF白蛋白指数的水平可作为化脓性脑膜炎和病毒性脑炎早期诊断、鉴别诊断,以及判断BBB损伤程度的参考指标。 相似文献
79.
Isolation and partial characterization of the tegumental outer membrane of schistosomula of Schistosoma mansoni 总被引:1,自引:0,他引:1
F Levi-Schaffer R Tarrab-Hazdai M D Schryer R Arnon M Smolarsky 《Molecular and biochemical parasitology》1984,13(3):283-300
Separation of the external membranes from freshly converted mechanical schistosomula of Schistosoma mansoni was achieved by osmotic shock under hypertonic conditions, followed by mechanical shearing and ultracentrifugation. Prior to treatment, the schistosomula were surface labeled by introduction of N-DNP-epsilon-aminocaproylphosphatidylethanolamine molecules into their lipid bilayer followed by anti-DNP antibodies and stained with either 125I-protein-A or ferritin labeled secondary anti-DNP antibodies. This label provided a membrane marker by which the purity of the preparation could be assessed at each stage. Fluorescence staining with FITC-conjugated secondary antibodies prior to treatment revealed that the homogeneously stained membrane of the intact schistosomula became swollen and ruptured after the osmotic shock. The isolated membrane pellet was intensely fluorescent. Electron microscopical examination revealed mostly vesicles, some of them with organized multilayer assembly. The vesicles were ferritin labeled, indicating that they originated from the outer surface membrane of the schistosomula. A 100 fold enrichment in the alkaline phosphatase activity and about 300 fold enrichment in acetylcholinesterase activity in the membrane preparations, as compared to the intact schistosomula, was found. The isolated tegument was analyzed by SDS-polyacrylamide gel electrophoresis. The pattern obtained showed three major bands, of molecular weights 69 000, 45 000 and 12 000 alongside with a large number of minor bands. Immunoprecipitation of the isolated 125I-labeled membrane antigens with antisera from chronically infected mice revealed these three major bands together with three other bands of molecular weight 38 000, 23 000 and 16 000. 相似文献
80.
Brian T. Butcher Carol E. ONeil Margaret A. Reed John E. Salvaggio Hans Weill 《The Journal of allergy and clinical immunology》1982,70(4):231-235
Toluene diisocyanate (TDI) sensitivity accompanied by nonspecific bronchial hyperresponsiveness occurs in approximately 5% of occupationally exposed workers. We report the case of a 32-yr-old worker followed longitudinally after removal from isocyanate exposure. TDI reactivity was lost 11 mo after removal from exposure and nonspecific bronchial hyperresponsiveness resolved after 17 mo. Bronchial reactivity to radishes (Raphanus sativus), which developed concurrently with TDI reactivity, was lost 2 yr later. Immunopharmacologic results show that the worker's initial decreased ability of lymphocytes to produce cyclic AMP returned to near normal after 2 yr. IgE antibodies to a human serum albumin tolyl monoisocyanate conjugate were still present at this time. 相似文献