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1.
M A Leon 《Science (New York, N.Y.)》1967,158(806):1325-1326
Concanavalin A precipitated less than 5 percent of immunoglobulin G from human serum. It reacted with all of 42 myeloma serums of the immunoglobulin G type tested, but no more than approximately 50 percent of the total myeloma protein was ever precipitated. The fact that not all of the protein was precipitated and that the amounts precipitated varied from serum to serum may be interpreted as demonstrating heterogeneity of the carbohydrate in these myeloma proteins. Other glycoproteins precipitated by concanavalin A were identified, and subsequently separated from concanavalin A by chromatography.  相似文献   

2.
The receptor with high affinity for immunoglobulin E (IgE) on mast cells and basophils is critical in initiating allergic reactions. It is composed of an IgE-binding alpha subunit, a beta subunit, and two gamma subunits. The human alpha subunit was expressed on transfected cells in the presence of rat beta and gamma subunits or in the presence of the gamma subunit alone. The IgE binding properties of the expressed human alpha were characteristic of receptors on normal human cells. These results now permit a systematic analysis of human IgE binding and a search for therapeutically useful inhibitors of that binding.  相似文献   

3.
KAY K  RIEKE WO 《Science (New York, N.Y.)》1963,139(3554):487-490
The type and fate of mononuclear cells of guinea pigs hypersensitive to tuberculin were studied by means of purified protein derivative labeled with I(125) and mononuclear cells labeled with tritiated thymidine. Purified protein derivative labeled with I(125) was taken up in vitro by lymphocytes and neutrophils from animals that were either sensitive or nonsensitive to tuberculin, but it was bound more frequently by the cells of sensitive animals. Passive transfer of tuberculin hypersensitivity by means of lymphocytes labeled with tritiated thymidine indicated that significant numbers of radioactive cells migrated to the site where the skin was tested with purified protein derivative only when the test was made immediately after transfusion. Although skin reactions from tests made with purified protein derivative 24 hours after transfusion were comparable to those from tests made immediately, the number of labeled cells at the sites of the later tests was not consistently larger than it was in controls (Histoplasmin reactions). Thus transfused tuberculin-sensitive cells are neither always attracted to the sites of the test with purified protein derivative nor are they required in large numbers at the site for a positive reaction to develop.  相似文献   

4.
Concentration of the complement protein C'lq was determined immunochemically in serums of individuals with a wide variety of immunoglobulin abnormalities. A significant correlation was observed between decreased concentration of C'lq and deficient synthesis of immunoglobulin G; C'lq was particularly diminished in subjects with congenital, sex-linked (Bruton) agammaglobulinemia. In contrast, two to five times the normal concentration of C'lq was found in the serum of three patients with heavy chain disease (subtype immunoglobulin G3). No significant relation was found between C'lq and concentrations of immunoglobulins A and M.  相似文献   

5.
A sensitive method for detecting cells containing antibody to beta-galactosidase has been devised. The enzyme attached to the cells containing antibody can hydrolyze a fluorogenic substrate and yield fluorescent products which are measured microphotofluorometrically. This method of detecting a few molecules of antibody is applicable to other enzyme antigen systems.  相似文献   

6.
目的 探讨类风湿关节炎(RA)患者外周血单个核细胞体外诱导成树突状细胞(DC)TIM4表达.方法 分离15例RA患者和10例正常对照外周血单核细胞,加入重组人巨噬集落形成因子(rhMCSF)、重组人白介素-4(rhIL-4)培养6d,再加入肿瘤坏死因子-α(TNF-α)培养1d.采用流式细胞仪检测DC诱导分化情况,实时荧光定量PCR和Western blot检测TIM4表达.结果 RA患者外周血单核细胞诱导分化成DC数量多于对照组(P<0.01),DC表达TIM4明显增加(P<0.01).结论 DC表达TIM4上调可能参与RA发病.  相似文献   

7.
8.
Human monocytes contain two distinct receptor sites, one specific for the third component of complement (C'3), the other for immunoglobulin G(gammaG). The two receptors may function either independently or cooperatively in the induction of phagocytosis. Ingestion of erythrocytes coated with immunoglobulin M antibody requires a relatively large number of bound C'3 molecules per cell. Ingestion of erythrocytes sensitized with gammaG antibody is independent of complement; however, the reaction is inhibited by concentrations of gammaG far below those in normal serum. Inhibition by gammaG-globulin is overcome by a relatively small number of bound C'3 molecules per cell. The two monocyte receptors exert a cooperative effect on ingestion by monocytes of erythrocytes coated with gammaG antibody in the presence of inhibitory amounts of free gammaG.  相似文献   

9.
10.
The Gm and Inv genetic factors, characteristic antigens of human immunoglobulin G, were detected in chimpanzee serums. All animals tested were Gm(a+, x-, b(l)-, b(2)-, b(3)+, b(4)+). Polymorphism was demonstrated for factors Gm(c), Inv(l), and Inv(b). Three of the subclasses of heavy polypeptide chains and both types of light polypeptide chains that are present in human immunoglobulin G were identified in chimpanzee serums.  相似文献   

11.
Almost all B cells in autoimmune mice with the viable motheaten (mev) mutation express the Ly-1 cell surface antigen, which marks a minor population of B cells constituting a separate lineage in normal mice. Immunoglobulins primarily of the M and G3 classes, which in both normal and mev mice contain high levels of lambda light chain, are produced in excess in mev mice. These and other observations suggest that the development of B cells that express Ly-1 is regulated independently from the development of B cells that do not express Ly-1. B cells bearing the Ly-1 surface antigen may play specialized roles in the normal immune system and in autoimmunity by regulating other B cells via lymphokines, by producing antibodies to self and certain foreign antigens, and by preferentially secreting immunoglobulin M and immunoglobulin G3.  相似文献   

12.
Hybrid (NZB x W)F(1) mice spontaneously develop antibodies to nuclear antigens (ANA) and DNA (ADNA) and are an animal model of human systemic lupus erythematosus. Immunofluorescent and electron microscopic observations of the choroid plexus and renal glomeruli of (NZB x W)F(1) mice reveal deposits of host immunoglobulin G (IgG) and the third complement component which appear shortly after the development of ANA and ADNA in the circulation. Additionally, enhancement of ADNA responses accelerates the appearance and severity of IgG deposits in the choroid plexus. The choroid plexus may be a favored site for the deposition of immune complexes and the neuropsychiatric findings in patients with systemic lupus erythematosus and some patients with acute or chronic infections may be related in part to immune complex disease of the choroid plexus.  相似文献   

13.
用模拟酸雨淋溶法研究红壤和红色石灰土的盐基迁移状况   总被引:1,自引:1,他引:1  
用模拟酸雨对红壤和红色石灰土的原状土柱进行连续淋溶,探讨土壤盐基的淋溶强度、容量以及土壤pH和交换性盐基的变化规律。结果指出,酸雨对红色石灰土的盐基淋溶强度和容量大于红壤。交换性盐基的淋溶速率也有同样趋势;土层厚度的增加能大大降低酸雨对盐基的淋溶强度、容量和淋溶速度;红壤的pH对酸雨淋溶较敏感。而红色石灰土的交换性盐基对酸雨的反应较敏感。所以就土壤酸化速率而言,以土壤pH为指标时,则红壤大于红色石灰土;但以盐基淋失量为指标时则相反。  相似文献   

14.
目的 :观察支气管哮喘患者在发病期外周血中的Th 1/Th 2型细胞因子水平的变化。方法 :采用双抗体夹心ELISA方法分别对哮喘患者发作期组 (n =15 )、缓解期组 (n =15 )及正常人对照组 (n =2 0 )外周血单核细胞 (PBMC)产生的Th 1/Th 2型细胞因子 (IL 2、IL 4、IL 10 )进行了测定。结果 :哮喘急性发作期患者PBMC产生的IL 2水平较正常对照组明显下降 (P <0 .0 5 ) ,而IL 4、IL 10水平均增高 (P <0 .0 5 ) ,缓解期恢复至正常水平。结论 :哮喘发病过程中Th 1/Th 2型细胞因子处于失衡状态 ,为哮喘的治疗提供指引  相似文献   

15.
Animal cells: noncorrelation of length of G1 phase with size after mitosis   总被引:6,自引:0,他引:6  
The interval between mitosis and initiation of DNA synthesis (G(1)) varied over a fourfold range for Chinese hamster ovary cells, an established line. This was not because of size differences. Synchlronous cells of different sizes began DNA synthesis at similar times after mitosis. A novel technique of centrifugation for separating cells according to size is described.  相似文献   

16.
Hepatic microsomal enzymes in man and rat: induction and inhibition by ethanol   总被引:10,自引:0,他引:10  
The feeding of ethanol increased significantly the activities of hepatic pentobarbital and benzpyrene hydroxylases in rats, and, in human volunteers, doubled pentobarbital hydroxylase activity. In vitro ethanol inhibited aniline, pentobarbital, and benzpyrene hydroxylases. These data may explain, at least in part, the increased tolerance of alcoholics to sedatives when sober, and the enhanced sensitivity to sedatives when inebriated.  相似文献   

17.
18.
Neuronal cell Thy-1 glycoprotein: homology with immunoglobulin   总被引:77,自引:0,他引:77  
The amino acid sequences of mouse brain Thy-1 glycoproteins are shown to be homologous to those of variable-region immunoglobulin domains. There is also good homology with constant domains and beta 2-microglobulin; overall the results suggest that Thy-1 may be like the primordial immunoglobulin domain. Preliminary evidence for an invertebrate Thy-1 homolog supports this possibility.  相似文献   

19.
20.
Oral administration of 4-bromo-3-hydroxybenzyloxyamine to normal humans resulted in decreased urinary excretion of histamine; the normal increase in urinary levels of histamine after oral histidine loading was prevented. In two patients having systemic mastocytosis, additional evidence of inhibition of biosynthesis of histamine included marked reduction in symptoms attributed to histamine, and prevention of symptomatic exacerbation associated with histidine loading.  相似文献   

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