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1.
When plasma containing a hepatitis-associated antigen (Au/SH) is fractionated, the antigen is localized in fractions III and IV with none in fraction II and only small amounts in fractions I and V. The amount of antigen found in each of these fractions is probably not predictive of clinical infectivity of Cohn ethanol fractions from normnal pooled plasna. 相似文献
2.
Interactions of immunoglobulins G and M in the detection of the mammalian C-type virus cross-reactive antigen 总被引：2，自引：0，他引：2
The mammalian C-type tumor viruses share an antigenic determinant, gs-3, located on the major internal polypeptide of the virion. Detection of this determined in gel diffusion assays by antiserums prepared in rats by immunization with rat tumor homogenates carrying murine virus and serums prepared in a rabbit by immunization with purified murine gs antigen depended on antibodies present in the fractions containing immunoglobulins M and G. The immunoglobulin G fraction by itself precipitated only the homologous murine antigen. Neither fraction alone precipitated heterologous (cat, rat, or hamster) antigen (definition of the gs-3 reaction), while a mixture of the two fractions did. The gs-3 reaction was eliminated by treatment of the serums with beta-mercaptoethanol, also indicating a requirement for immunoglobulin M antibodies. 相似文献
3.
以21日龄杜大长断奶仔猪为研究对象,探讨了大豆抗原蛋白对其生长性能和肠道免疫核因子的影响。结果表明,与对照组相比,试验组断奶仔猪日均采食量降低了25.88%(P<0.01);日增重下降了28.70%(P<0.01),腹泻率提高了58.77%(P<0.01);木糖吸收试验表明试验组仔猪在第1,2,3,4,5 h后血浆中木糖浓度分别比对照组低62.39%(P<0.01),68.54%(P<0.01),67.27%(P<0.01),67.98%(P<0.01)和69.95%(P<0.01);试验组断奶仔猪空肠和回肠组织绒毛长度分别降低27.56%(P<0.01)和22.43%(P<0.01),隐窝深度分别提高30.01%和53.03%(P<0.01)。十二指肠绒毛长度和隐窝深度差异不显著;空肠黏膜核因子NF-κB活性提高了71.87%(P<0.01)。结果提示,日粮中大豆抗原蛋白对断奶仔猪的生长性能产生了显著的负面影响,大豆抗原蛋白可能通过调控肠道黏膜组织核因子活性,影响了断奶仔猪肠道粘膜的形态和结构,进而影响采食量,腹泻率和生长性能。 相似文献
4.
The HL-A7 antigen of human leukocytes occurs as a soluble, low-density lipoprotein in the serum of HL-A7-positive individuals. Its presence in high concentration may inhibit direct leukocyte grouping, leading to erroneous results. This finding affords an easy method for the preparation of monospecific cytotoxic antiserums by absorption with serum fractions rather than leukocytes. 相似文献
5.
The circumsporozite protein, a surface antigen of the sporozoite stage of the monkey malarial parasite Plasmodium knowlesi, was expressed in the yeast Saccharomyces cerevisiae by using an expression vector containing the 5' regulatory region of the yeast alcohol dehydrogenase I gene. It was necessary to eliminate the entire 5' upstream region of the parasite DNA to obtain the expression of this protein. Only the circumsporozoite precursor was produced by the yeast transformants, as detected by immunoblotting. About 55 and 20 percent of the circumsporozoite protein produced in yeast was associated wtih the 25,000 g and 150,000 g particulate fractions, respectively. The protein could be solubilized in Triton X-100 and was stable in solubilized extracts. 相似文献
6.
Australia antigen (hepatitis B antigen): a conformational antigen dependent on disulfide bonds 总被引：14，自引：0，他引：14
Reduction and alkylation of purified hepatitis-associated Australia antigen (hepatitis B antigen) resulted in a total loss of serologic activity. The reduced and alkylated protein formed a single band with a sedimentation coefficient of 31S on analytical ultracentrifugation, and no subunits were detected by Sephadex gel filtration. Although this preparation induced a delayed hypersensitivity response when injected into guinea pigs, it failed to stimulate humoral antibody formation. The data suggest that hepatitis B antigen is a conformational antigen critically dependent upon the disulfide bonds of the protein moiety. 相似文献
7.
Goat antibodies to idiotypes (anti-idiotypic antibodies; Ab2) that recognize an idiotype associated with the combining site of a BALB/c mouse IgG2a monoclonal antibody (Ab1) to human gastric carcinoma were used to immunize BALB/c mice and rabbits. A monoclonal anti-anti-idiotypic antibody (Ab3) of IgG1 isotype was obtained after immunization of mice. The Ab3 and the Ab1 showed identical binding specificities and bound with similar avidities to the same tumor antigen. The induction of Ab1-like Ab3 by Ab2 was not restricted to mice, since Ab3 could also be induced in rabbits. Both the mouse- and the rabbit-derived Ab3 bound the same gastrointestinal cancer-associated antigen as Ab1. These findings indicate that Ab2 induced the formation of antigen-specific Ab3, probably because it bears the internal image of the tumor-associated antigen. This Ab2 may therefore have potential for modulating the immune response of cancer patients to their tumors. 相似文献
8.
Cytostructural localization of a tumor-associated antigen 总被引：2，自引：0，他引：2
Tumor cell membrane glycoproteins may be involved in the induction of tumor immunity or in the escape of tumors from immunologic defense mechanisms. Forty-four benign and malignant breast lesions were examined for the presence of a carbohydrate precursor antigen (T antigen) of the human blood group system MN. T antigen was demonstrated by means of an immunohistochemical technique to detect tissue binding of peanut agglutinin, a plant lectin, with affinity for T antigen. Malignant breast lesions showed a pattern of T antigen expression different from that of benign breast tissues. A possible role for T antigen in the modulation of the immune response to breast carcinoma is suggested. 相似文献
9.
10.
伏马菌素B_1人工抗原的构建 总被引：1，自引：0，他引：1
碳化二亚胺法将伏马菌素B1(fumonisin B1,FB1)与载体蛋白进行偶联制备免疫抗原FB1-BSA及包被抗原FB1-OVA,比较了不同偶联条件对抗原合成的影响。紫外扫描初步显示载体蛋白与伏马菌素偶联成功。皮下注射免疫BALB/c小鼠,获抗FB1多克隆抗体,间接非竞争ELISA分析所得抗血清效价,最高可达1∶23000,间接竞争ELISA显示所制备的抗血清能有效识别伏马菌素B1,与脱氧雪腐镰刀菌烯醇(DON)、玉米赤霉烯酮(ZEN)、T-2毒素无交叉反应。 相似文献
11.
Australia antigen: detection and transmission in shellfish 总被引：2，自引：0，他引：2
P Mahoney G Fleischner I Millman W T London B S Blumberg I M Arias 《Science (New York, N.Y.)》1974,183(4120):80-81
Australia antigen was found in clams contaminated by drainage of untreated sewage from a coastal hospital. In closed-system aquariums, the antigen was ingested by clams and transmitted to previously uninfected clams. In opensystem aquariums, the titer of Australia antigen decreased with time, suggesting viral concentration rather than replication. 相似文献
12.
培养表达小瓜虫抑动抗原的重组四膜虫(Tetrahymena thermophila)G1株,诱导表达小瓜虫的抑动抗原,采用非离子型去污剂Triton X-114提取虫体膜蛋白,然后通过亲和层析法纯化抑动抗原。采用ELISA、SDS-PAGE和Western Blotting分析所提取的抑动抗原的纯度及免疫学特性。结果表明:通过亲和层析能够得到重组四膜虫所表达的G1抑动抗原蛋白,它与相应血清型小瓜虫抑动抗原的分子量和免疫原性相近,其分子量为44 kDa(还原条件)或36 kDa(非还原条件)。 相似文献
13.
J H Peters 《Science (New York, N.Y.)》1967,157(793):1200-1202
Specific heterophile reactive antigen has been localized by means of indirect immunofluorescence in 12 of 13 kidney biopsy specimens obtained during the acute phase of infectious mononucleosis. I feel that this may represent the identification of infectious agent antigen. Evidence is also presented for the possible existence of two different strains of the agent of infectious mononucleosis. 相似文献
14.
L R Sibal W F Feller M A Fink B E Kohler W T Hall H E Bond 《Science (New York, N.Y.)》1969,164(875):76-78
A rapid, sensitive immuno-assay for mammary tumor virus antigen based on inhibition of passive hemagglutination has been developed. The method permits measurement of this antigen in mouse milk from which the fat has been removed. 相似文献
15.
Identification and characterization of a neuron-specific nuclear antigen in Drosophila 总被引：7，自引：0，他引：7
An antigen found only in neuronal nuclei of Drosophila melanogaster is revealed by staining with a monoclonal antibody (Mab44C11). This antigen appears early in development, before neurons show any other signs of antigenic or morphologic differentiation, and persists throughout development. This nuclear staining permits reliable detection of neurons in developmental studies of wild-type and mutant flies. Protein immunoblot analyses and immune precipitation experiments show that the neuronal nuclear antigen is a 50-kilodalton polypeptide. 相似文献
16.
Thaunat O Granja AG Barral P Filby A Montaner B Collinson L Martinez-Martin N Harwood NE Bruckbauer A Batista FD 《Science (New York, N.Y.)》2012,335(6067):475-479
During the activation of humoral immune responses, B cells acquire antigen for subsequent presentation to cognate T cells. Here we show that after mouse B cells accumulate antigen, it is maintained in a polarized distribution for extended periods in vivo. Using high-throughput imaging flow cytometry, we observed that this polarization is preserved during B cell division, promoting asymmetric antigen segregation among progeny. Antigen inheritance correlates with the ability of progeny to activate T cells: Daughter cells receiving larger antigen stores exhibit a prolonged capacity to present antigen, which renders them more effective in competing for T cell help. The generation of progeny with differential capacities for antigen presentation may have implications for somatic hypermutation and class switching during affinity maturation and as B cells commit to effector cell fates. 相似文献
17.
A neuronal antigen in the brains of Alzheimer patients 总被引：44，自引：0，他引：44
A monoclonal antibody was prepared against pooled homogenates of brain tissue from patients with Alzheimer's disease. This antibody recognizes an antigen present in much higher concentration in certain brain regions of Alzheimer patients than in normal brain. The antigen appears to be a protein present in neurons involved in the formation of neuritic plaques and neurofibrillary tangles, and in some morphologically normal neurons in sections from Alzheimer brains. Partial purification and Western blot analysis revealed the antigen from Alzheimer brain to be a single protein with a molecular weight of 68,000. Application of the same purification procedure to normal brain tissue results in the detection of small amounts of a protein of lower molecular weight. 相似文献
18.
Exposure of human Wi-38 cells to human serums containing Australia antigen, and presumably serum hepatitis virus, renders the cells refractory to infection by Newcastle disease virus as detected by the hemadsorption-negative plaque test for intrinsic interference. Induction of the Newcastle disease virus refractory state could be passed in cell culture with up to a 1 : 100,000 dilution of material obtained from cells "infected" with serums containing Australia antigen after filtration (0.45-microm pores) and heating to 60 degrees C for 1 hour. Human antiserums to the Australia antigen prevented induction of the Newcastle disease virus refractory state. 相似文献
19.
利用鸡鲍氏志贺氏菌和鸡痢疾志贺氏菌制备多价凝集抗原,确定其最佳反应浓度及比例.选择合适的试验鸡只,用2种鸡志贺氏菌灭活疫苗定期肌肉注射免疫和抗体效价测定,适时采血分离血清.结果显示,鸡鲍氏抗原与痢疾抗原的最佳混合浓度为6×10~9mL~(-1),最佳比例为1:1.制备的鸡鲍氏和鸡痢疾志贺氏菌多价阳性血清,经抗体效价测定均达6log2,阴性血清与鸡志贺氏菌多价凝集抗原作用无凝集现象出现.研制的多价凝集抗原及其标准血清经特异性试验、重复性试验和保存方法试验,具有特异性强、敏感性高、重复性好、易保存等特点,且可省去单价凝集抗原繁琐的检测程序和时间. 相似文献
20.
Dudziak D Kamphorst AO Heidkamp GF Buchholz VR Trumpfheller C Yamazaki S Cheong C Liu K Lee HW Park CG Steinman RM Nussenzweig MC 《Science (New York, N.Y.)》2007,315(5808):107-111
Dendritic cells (DCs) process and present self and foreign antigens to induce tolerance or immunity. In vitro models suggest that induction of immunity is controlled by regulating the presentation of antigen, but little is known about how DCs control antigen presentation in vivo. To examine antigen processing and presentation in vivo, we specifically targeted antigens to two major subsets of DCs by using chimeric monoclonal antibodies. Unlike CD8+ DCs that express the cell surface protein CD205, CD8- DCs, which are positive for the 33D1 antigen, are specialized for presentation on major histocompatibility complex (MHC) class II. This difference in antigen processing is intrinsic to the DC subsets and is associated with increased expression of proteins involved in MHC processing. 相似文献