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91.
Mario Geller M.D. Dennis K. Flaherty Ph.D. Helen A. Dickie M.D. Charles E. Reed M.D. 《The Journal of allergy and clinical immunology》1977,59(6):445-448
Each of 5 patients with acute nitrofurantoin pleuropulmonary reactions had profound lymphopenia and 4 had eosinophilia developing early in the clinical course after the drug was withdrawn. The 2 patients tested had only one third of the normal numbers of E rosettes (T lymphocytes) in the peripheral blood during recovery. Lymphoblastic transformation tests with purified nitrofurantoin were done in 3 patients and all of them were negative; responses to phytohemagglutinin, concanavalin A, and pokeweed were decreased but still normal. The diagnosis of various nitrofurantoin hypersensitivity reactions relies on clinical data. The mechanisms of these reactions presently remain unclear. 相似文献
92.
The peptide melittin, the main constituent of bee venom is a potent stimulus for the generation of an eosinophil chemotactic factor (ECF) from human polymorphonuclear neutrophils, rat mast cells and rat peritoneal cells depleted in mast cells. Optimal EFC induction required a sublytic activation of the cells. With each cell type the kinetics of ECF generation were similar in that after an early rise in activity a steep fall off occurred at later times of incubation suggesting a mechanism of inactivation. The induction of ECF by melittin is increased in the presence of calcium. The polar portion of the melittin molecule (aminoacids 20–26) is responsible for the generation of the chemotactic activity. Other peptides of honey bee venom such as the mast cell degranulating peptide (MCD) or apamine do not initiate ECF release. It appears that melittin leads to ECF induction via the phospholipase A2-arachidonic acid dependent pathway of cell activation. Our data suggests that the lipid mediator ECF can be obtained from phagocytes and mast cells thus indicating the interdependence of inflammatory reactions. 相似文献
93.
We designed experiments in this study to test the hypothesis suggested by recent purification data that blood basophils comprise two populations of different density, which circulate in numbers characteristic for each human subject. Basophils were separated into two density bands by single step centrifugation on a discontinuous Percoll gradient. Band 1 cells were at the interface between plasma and Percoll of density 1.070 gm/ml. Band 2 cells were at the Percoll 1.070 to 1.080 interface. When the number of band 1 basophils was expressed as a percentage of the total in bands 1 and 2, this relative amount generally remained in a narrow range for blood obtained from the same donor on 3 successive days but differed markedly in different individuals. In a series of leukapheresis experiments, we demonstrated that the percentage of band 1 basophils in postleukapheresis venous blood was strikingly similar to the preleukapheresis value. If basophils that repopulated the leukapheresis-depleted circulation came from the bone marrow, we can conclude that blood levels of basophils in bands 1 and 2 are under physiologic control and that the two types of basophils are released in amounts characteristic for each human subject. Additional evidence for two distinct blood basophil populations was provided by histamine measurements. The histamine content per basophil was consistently higher in cells from band 1 than from band 2, the mean difference between pairs of values for 30 subjects being 0.3 +/- 0.04 pg or about 27% of the band 1 basophil histamine content of 1.1 pg. 相似文献
94.
目的探讨噬菌体展示随机肽库技术在结核分枝杆菌培养滤过蛋白10(CFP-10)/早期分泌抗原靶点6(ESAT-6)融合蛋白(CE融合蛋白)模拟抗原表位筛选中的应用。方法以抗CE融合蛋白多克隆抗体为靶分子,对随机噬菌体7肽库进行筛选,经3轮生物淘选后,随机选取18个单噬菌体进行测序分析。采用双抗体夹心和竞争ELISA方法对测序后噬菌体进行阳性克隆及其活性鉴定。采用间接ELISA方法,选取阳性单噬菌体与CE融合蛋白分别对20份活动性肺结核患者和10份有卡介苗接种史健康人的血清标本抗体进行检测。结果经过3轮生物淘选,能与靶分子特异性结合的噬菌体得到了明显富集。18个单噬菌体测序共获得9种序列,其中单噬菌体5、6、18的氨基酸序列均包含Trp-Asp-Ala-Thr(WDAT)保守序列,该序列与ESAT-6第58-61位氨基酸的序列一致。9种序列中各取1个单噬菌体经双抗体夹心和竞争ELISA检测,有7个单噬菌体(1、5、6、10、13、14、18,S/N值依次为9.2、9.7、9.4、8.9、9.6、9.9、9.0)确定为具有免疫活性的阳性克隆。选取含有WDAT保守序列的阳性单噬菌体5与CE融合蛋白分别对2种血清标本抗体进行间接ELISA检测结果显示,单噬菌体5对2种血清标本抗体检测的吸光度值均高于CE融合蛋白(分别为0.931±0.298 vs 0.317±0.157、0.496±0.073 vs 0.118±0.026,均P〈0.05);单噬菌体5对活动性肺结核患者血清标本抗体的检出率(95%,19/20)明显高于CE融合蛋白(60%,12/20),而对有卡介苗接种史健康人血清标本抗体的检出率(9/10)低于CE融合蛋白(10/10)。结论利用噬菌体展示随机肽库技术成功筛选出7个CE融合蛋白的模拟抗原表位,并获得了定位于ESAT-6第58-61位氨基酸序列的CE融合蛋白的1个线性B细胞抗原表位,提高了ELISA检测的敏感性,为进一步研究CE融合蛋白的? 相似文献
95.
Robert F. Todd Stefan C. Meuer Paul L. Romain Stuart F. Schlossman 《Human immunology》1984,10(1):23-40
Previous studies using conventional hetero- or isoantisera have indicated the involvement of class II (Ia) molecules in presentation of soluble by monocytes to inducer T lymphocytes, stimulation of inducer T cells in MLR, and recognition of Ia-bearing targets cells by cytotoxic T lymphocytes (CTL). The experience in using monoclonal anti-Ia reagents capable of blocking these phenomena in the human system is limited. Recently, however, we have characterized a lytic IgG2a monoclonal antibody, 9–49, that binds to functionally significant class II molecules. This antibody blocks (in the absence of complement): (1) specific binding of peripheral blood lymphocytes (PBL) to antigen-pulsed monocyte monolayers, (2) proliferation of PBL in response to soluble antigen (tetanus toxoid or mumps) or cell surface class II antigen stimulation in allogeneic or autologus MLR, (3) proliferation of cloned T4+ (inducer) lymphocyte cell lines to class II antigens, (4) generation of cytotoxic lymphocytes during allogenic MLR, and (5) recognition (and killing) of class II-bearing target cells by T4+ CTL clones. Proliferation and CTL activity of a T8+ clone is unaffected by the 9–49 antibody. These results indicate the usefulness of this monoclonal reagent in studies evaluating the functional role of Ia molecules in immune recognition phenomena. 相似文献
96.
The IgG subclasses of immunoglobulin for intravenous injection (IVIg) were investigated after various different types of treatment.
The level of IgG2 was relatively low in preparations treated with pepsin, but by changing the clone producing anti-IgG2 antibody,
the level approached that of normal human serum. Though undetectable in sulfonated immunoglobulin preparations, IgG3 was detected
after reoxidation. When determining the IgG subclasses of IVIg, it must be kept in mind that the apparent value may subsequently
become lower due to the depressed reaction of the antibody. 相似文献
97.
Roy Patterson Irena M. Suszko Stephen G. Hendrix C.Raymond Zeiss 《The Journal of allergy and clinical immunology》1981,67(2):162-165
Aqueous extracts of tree pollen were partially purified and polymerized with methods previously established for preparation of ragweed and grass polymers. The polymerized tree preparations were antigenic as demonstrated by ability to elicit immediate-type skin reactivity in humans and to induce an immune response in rabbits. The polymerized tree antigen was 100- to 10,000-fold less skin reactive than monomer tree antigen in tree pollen-sensitive patients but both preparations had similar antigenicity in rabbits. These results demonstrate that polymerized tree antigens can be prepared and should have the therapeutic potential already demonstrated for polymerized ragweed preparations. 相似文献
98.
Mouse monoclonal antibodies to the human C3b receptor 总被引:7,自引:0,他引:7
J Cook E Fischer C Boucheix M Mirsrahi M H Jouvin L Weiss R M Jack M D Kazatchkine 《Molecular immunology》1985,22(5):531-539
Mouse monoclonal antibodies were raised against the human C3b receptor (CR1) molecule that had been purified from solubilized erythrocytes membranes. Four hybridomas were selected, cloned and expanded because their supernatants reacted strongly with insolubilized CR1 by ELISA and intensely stained B-dependent areas of the spleen and glomerular podocytes by indirect immunofluorescence. The four monoclonal antibodies, named J3D3, J8B10, J3B11 and J7C2, were IgG1 immunoglobulins. J3D3 immunoprecipitated two protein bands of apparent mol. wts 200,000 and 220,000 from 125I-surface-labeled human erythrocytes, which correspond to the two major allotypic forms of CR1. By indirect immunofluorescence, monoclonal antibodies stained polymorphonuclear leucocytes (PMN), most peripheral blood B-cells and a small subset of peripheral blood T-cells. J3D3 bound to CR1 on erythrocytes, PMN and lymphocytes with an affinity of 1-3 X 10(9) M-1 and recognized 170-1330 antigenic CR1 sites with an average of 740 sites/erythrocyte in 100 healthy individuals, approx. 50,000 sites/PMN and 15,000 sites/lymphocyte. There was a bimodal distribution of CR1 numbers on erythrocyte in the normal population. The four monoclonal antibodies similarly inhibited CR1-mediated decay of preformed cell-bound alternative- and classical-pathway C3 convertase sites. Two antibodies, J3D3 and J3B11, inhibited C3b-dependent rosette formation with lymphocytes, although much less efficiently than F(ab')2 polyclonal anti-CR1 antibody. Differences that were observed in the relative capacity of the antibodies to inhibit some of the functions of CR1 and in their ability to compete for binding of 125I-J3D3 to CR1 on erythrocytes, suggested that they are directed against different epitopes on CR1. Monoclonal antibodies provide useful means to assess and analyze the biological and immunoregulatory functions of the C3b receptor. 相似文献
99.
Zusammenfassung Eine optimale Behandlung des Hodgkin-Patienten setzt die Kenntnis des Ausbreitungsstadiums voraus. Laboruntersuchungen, Röntgen und Nuklearmedizin reichen gewöhnlich nicht aus, um dies mit ausreichender Sicherheit festzustellen. Es sind in der Regel Biopsien von Knochenmark und Leber erforderlich. In besonderen Fällen werden auch eine Laparoskopie oder explorative Laparotomie und Splenektomie empfohlen. Als optimale Therapie tritt in den auf Lymphknotenregionen beschränkten Ausbreitungsstadien die Strahlentherapie in den Vordergrund, bei ausgeprägten Allgemeinsymptomen und bei Organbefall eine zytostatische Behandlung. Diagnostik und Therapie sollten individuell gehandhabt werden. Neue therapeutische Vorstellungen müssen kritisch an den z.T. hervorragenden Ergebnissen gemessen werden, die von verschiedenen Arbeitsgruppen erreicht wurden.Herrn Professor Dr. Dr. h. c. H.E. Bock zum 75. Geburtstag in Verehrung und Dankbarkeit gewidmet 相似文献
100.
W H Yang G Dorval C K Osterland N J Gilmore 《The Journal of allergy and clinical immunology》1979,63(5):300-307
Chronic immunization may lead to the production of circulating immune complexes (CICs). This study was undertaken to determine the presence of circulating IgG immune complexes in 95 subjects with allergic rhinitis/asthma receiving immunotherapy, 46 individuals with similar diagnosis but not on immunotherapy, and 64 healthy controls. Modified Raji cell and murine leukemia cell (L-1210) assays, selected for a high density of Fc receptors and devoid of Epstein-Barr virus membrane antigen, were used. Other immunological parameters such as immunologlobulins G, A, M, E, and rheumatoid factor activity were also studied. The CIC concentrations in the treated group did not differ significantly from the untreated group, although both groups did have a significantly higher concentration than the healthy controls. The presence of CICs has no relationship with age or sex of patients, dosage of allergen administered, number and nature of allergens received, period between the time of last injection and the blood sampling, and the duration of immunotherapy. Serum IgG, IgA, IgM, and rheumatoid factor activity did not differ between the treated and untreated groups. IgE was significantly higher in the treated group when compared with the untreated, and IgE levels in treated patients with elevated CICs were significantly increased compared with CIC-negative treated patients. These data suggest that CICs are present in serum of atopic diseases such as allergic rhinitis/asthma. Significantly, an association of elevation of CICs with immunotherapy could not be demonstrated. 相似文献