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51.
This investigation uses a system for inducing and detecting anti-tetanus toxoid antibody (anti-TT) synthesis to study specific antibody (Ab) synthesis by bone marrow mononuclear cells (MC). We measured the amounts of anti-TT secreted and the number of B cells secreting antibody (Ab). The ELISA plaque detects single B cells secreting specific Ab. The results show that (1) spontaneous anti-TT secretion by MC is higher than spontaneous anti-TT secretion by peripheral blood lymphocytes (PBL) using an ELISA plaque (P<0.01); (2) spontaneous anti-TT production by MC correlated with the serum anti-TT titers as measured by an ELISA (r=0.75,P=0.005); (3) two types of marrow B cells were identified—one that spontaneously secretes anti-TT and another that produces anti-TT after TT-stimulation; (4) the frequency of anti-TT-secreting B cells is higher in MC than in PBL; (5) the amount of Ab secreted per marrow B cell is not different from that secreted by a peripheral B cell; and (6) marrow B cells could be induced to produce anti-TTin vitro up to 10 months without added cytokines. These results show that bone marrow is a major repository for differentiated B cells that spontaneously produce Abs to maintain circulating Abs titers and for memory B cells that can be induced to produce specific Ab.  相似文献   
52.
目的构建人免疫缺陷病毒1型(HIV-1)特异性噬菌体抗体库,制备人源抗HIV-1gp120单克隆抗体。方法以半巢式聚合酶链反应(PCR)从HIV-1感染者外周血单个核淋巴细胞中扩增抗体重链Fd和轻链(k)基因,与噬菌体载体pComb3连接,构建噬菌体抗体Fab组合文库。对抗体库进行3轮吸附-洗脱-扩增的亲和选择后,以ELISA法筛选抗HIV-1gp120噬菌体抗体,并进行DNA序列分析和Fab的可溶性表达。结果半巢式PCR有效地扩增出Fd和k基因,以此构建成容量为195×107的噬菌体抗体库。3轮亲和选择使特异性抗体得到高度富集,抗HIV-1gp120噬菌体抗体阳性克隆占32%。对一阳性克隆抗体基因CH1和CL部分DNA序列进行了测定,并在大肠杆菌表达出可溶性Fab。结论抗HIV-1特异性噬菌体抗体库的构建和人源抗HIV-1gp120单克隆抗体的制备为今后筛选抗HIV中和抗体奠定了基础,具有重要的应用价值。  相似文献   
53.
Antigen-specific vaccines are one of several molecularly targeted approaches under investigation as possible treatments for prostate cancer. Important to the development of vaccines is the identification of appropriate target antigens. We hypothesized that antigens of the prostate might be identified in patients with the chronic prostatitis/pelvic pain syndrome, a syndrome for which an autoimmune pathology has been proposed. Such antigens might represent naturally recognized target antigens of the prostate that could be investigated in the future as prostate tumor antigens. In this report, we used SEREX to identify proteins expressed in a prostate cDNA expression library recognized by IgG from the sera of patients with chronic prostatitis. Candidate proteins were evaluated using a panel of sera from 62 subjects with symptomatic prostatitis and 71 control male blood donors. We identified one protein that was recognized primarily in sera from subjects with prostatitis compared with controls. MAD-PRO-34, a nucleolar autoantigen, was recognized in 6/62 subjects and 0/71 controls (p = 0.00897). This protein had previously been identified as an autoantigen in patients with prostate cancer. In addition, the NY-CO-7 protein was recognized in 9/62 subjects and 3/71 controls (p = 0.0654). Two subjects had IgG specific for both the MAD-PRO-34 and NY-CO-7 gene products. Our results demonstrate that some patients with the chronic prostatitis/pelvic pain syndrome have autoantibodies to specific proteins. Proteins identified, and MAD-PRO-34 in particular, could be further investigated as potential prostate tumor antigens.  相似文献   
54.
Inhibiting complement anaphlytoxin C5a during sepsis may prevent sepsis mortality. Although human anti-C5 antibodies exist, their therapeutic use in microbial sepsis has been avoided because of the hypothesis that inhibiting C5b will prevent formation of the bactericidal membrane attack complex (MAC) and worsen clinical outcome. We wished to test the hypothesis that inhibition of C5 would improve outcomes in sepsis. Sepsis was induced in rats by laparotomy and cecal ligation and puncture (CLP) by an IACUC-approved protocol. Sham animals underwent laparotomy without CLP. Following CLP rats were randomized to receive a single IV dose of purified IgG ant-C5 antibody (Ab) or control IgG Ab. Anti-C5 Ab treated rats (n = 20) had significantly lower mortality vs. controls (n = 21), 20% vs. 52% (P = 0.019, log-rank). Analysis of bacterial load by culture of spleen and liver homogenates showed a reduction in colony forming units in anti-C5 Ab treated rats vs. control IgG (P = 0.003 and 0.009, respectively). Anti-C5 treatment reduced lung injury as measured by total MPO content of lung tissue (P = 0.024). Finally, rats genetically deficient in C6 production, unable to form MAC but capable of producing C5a and C5b, were protected from CLP-induced sepsis mortality. Our results show that in anti-C5 antibody therapy prevents CLP sepsis-induced mortality and improves lung injury. Inhibition of the complement MAC does not increase bacterial load or mortality, therefore, the use of anti-C5 therapy may be beneficial rather than detrimental in sepsis.  相似文献   
55.
目前国外已有制备抗人血管内皮细胞(VEC)单克隆抗体(McAb)成功的报道。但国内尚无这方面的报导。国外一些实验室所制得的抗人VEC的McAb,有的与单核细胞或(和)淋巴细胞具有交叉反应,有的作用于细胞质抗原而非膜抗原。Cerilli认为,VEC具有独特的非HLA抗原,而外周血单核细胞也具有这种VEC抗原系统。迄今尚未有人尝试  相似文献   
56.
重组Rab8截短体蛋白的原核表达、纯化和抗体制备   总被引:1,自引:0,他引:1  
目的 获得Rab8纯化蛋白,制备多克隆抗体,为深入研究Rab8在病毒感染宿主细胞过程中的作用奠定基础.方法 首先从HepG2细胞中克隆Rab基因,然后从Rab8质粒中亚克隆Rab8 C端编码122个氨基酸的基因片段,构建Rab8与6His的融合蛋白原核表达质粒.原核表达与蛋白纯化后,免疫动物,制备Rab8多克隆抗体.采用ELISA法检测其效价.Western检验抗体特异性,间接免疫荧光染色法验证其免疫组化特性.结果 克隆了人Rab8编码基因,构建了表达Rab8 C端编码122个氨基酸的原核表达质粒pQE31-Rab8-122,经过大肠杆菌表达、镍亲和层析柱纯化,获得相对分子量约15 000的融合蛋白,免疫Balb/c小鼠后收获抗血清.ELISA显示抗体效价达1/20 000.Western blot和免疫荧光染色结果显示此多克隆抗体能够与原核表达的Rab8蛋白发生特异性反应,并能够识别HepG2细胞中内源性Rab8蛋白.结论 本研究获得原核表达的Rab8纯化蛋白,成功的制备了Rab8多克隆抗体,为进一步研究Rab8参与病毒感染宿主细胞提供了重要的实验材料.  相似文献   
57.
Summary In order to study the long-term immunogenicity of interferon-2c (Berofor) in cancer patients, serum was collected starting in 1983 from study patients with various proliferative diseases who received interferon-2c at different doses, according to different schedules, and via different routes. A total of 1992 samples were tested for the presence of anti-interferon-2c antibodies. Due to long-term interferon-2c treatment, 346 patients were eligible for induction of neutralizing anti-interferon antibodies over a treatment period of 252 months. Most patients were treated for longer than 6 months. Of the 346 patients, three patients (0.87%) exhibited measurable titers of neutralizing antibodies following therapy with interferon-2c. One hundred and sixty-three patients suffered from non-Hodgkin lymphomas, leukemias, and preleukemias. One patient with chronic myeloid leukemia experienced antibody induction under therapy. The other 183 patients had solid tumors. Two of them reacted with antibody production. All titers were very low (1:12, 1:8, and 1:64). Compared with figures reported for other interferon- preparations, the propensity of interferon-2c to induce neutralizing antibodies seems to be very low. This property might be related to arginines occurring as critical residues in positions 23 and 34 of the interferon-2c molecule.Abbreviations ANB antiviral neutralization bioassay - CE competitive sandwich ELISA - EBI Ernst Boehringer Institut - IFN interferon  相似文献   
58.
CD1d-restricted NKT cells are a novel T cell lineage with unusual features. They co-express some NK cell receptors and recognize glycolipid antigens through an invariant T cell receptor (TCR) in the context of CD1d molecules. Upon activation through the TCR, NKT cells produce large amounts of IFN-gamma and IL-4. It has been proposed that rapid cytokine output by activated NKT cells may induce bystander activation of other lymphoid lineages. The impact of CD1d-restricted NKT cell activation in the induction of B cell-mediated immune responses to infection is still unclear. We show here that CD1-restricted NKT cells contribute to malarial splenomegaly associated with expansion of the splenic B cell pool and enhance parasite-specific antibody formation in response to Plasmodium berghei infection. The increased B cell-mediated response correlates with the ability of NKT cells to promote Th2 immune responses. Additionally, antibody responses against the glycosylphosphatidylinositol (GPI)-anchored protein merozoite surface protein 1 (MSP-1) were found to be significantly lower in CD1(-/-) mice compared to wild-type animals. P. berghei-infected MHC class II (MHCII)(-/-) mice also generated antibodies against MSP-1, suggesting that antibody production against GPI-anchored antigens in response to malaria infection can arise from both MHCII-dependent and independent pathways.  相似文献   
59.
根据自身免疫性甲状腺疾病发病机制的独特型-抗独特型免疫免疫学说,用兔抗人TSHAb检测TSH抗独特型抗体(TSHAb2)。以正常人为对照,以其结合率^-x+2s为正常值上限,大于此值为阳性。60例TRAb阳性病人,65%病人TSHAb2阳性,而40例TRAb阳性病人中,只有5%病人TSHAb2阳性。两组差异显著(P〈0.05)。TRAb和TSHAb2呈正相关(r=0.645,P〈0.01)。同时用  相似文献   
60.
BACKGROUND: The hemagglutination inhibition (HI) assay is a frequently used method to screen human sera for antibodies against influenza A viruses. Because HI has relatively poor sensitivity in detecting antibodies against avian influenza A strains, a more complicated microneutralization (MN) assay is often preferred. Recent research suggests that the sensitivity of the HI assay can be improved by switching from the traditionally used turkey, guinea pig, human, or chicken RBCs to horse RBCs. OBJECTIVE: To evaluate the performance of the horse RBC HI when screening for human antibodies against avian influenza types H3, H4, H5, H6, H7, H9, H11, and H12. STUDY DESIGN: We evaluated the reproducibility of horse RBC HI and its agreement with MN results using sera from people exposed or not exposed to wild and domestic birds. RESULTS: The horse RBC HI assay had high reliability (90%-100%) and good agreement with MN assay results (52%-100%). CONCLUSION: The horse RBC HI assay is reliable, less expensive, less complex, and faster than the MN assay. While MN will likely remain the gold standard serologic assay for avian viruses, the horse RBC HI assay may be very useful as a screening assay in large-scale epidemiologic studies.  相似文献   
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