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31.
The induction of immune responses in vivo is typically performed with antigens administered in external adjuvants, like alum, complete Freund's adjuvant, LPS and, more recently, monophosphoryl lipid A (MPL). However, the role of the adjuvant is still poorly defined. The aim of this study was to test whether the MPL affects the function of antigen-presenting cells (APC) in vitro and in vivo. Antigen-pulsed APC [including macrophages, B cells and dendritic cells (DC)] were incubated or not with MPL, and their ability to sensitize naive T cells was tested in vitro and in vivo. The data show that MPL enhances the ability of macrophages and B cells to sensitize naive T cells, and confers to them the capacity to induce the development of T(h)1 and T(h)2. Administration of MPL i.v. in mice results in the redistribution of fully mature DC in the T cell area of the spleen. These observations suggest that MPL may induce an antigen-specific primary immune response by provoking the migration and maturation of DC that are the physiological adjuvant of the immune system.  相似文献   
32.
Using short term CTL lines derived from HLA A2/Kb transgenic mice and IFN-gamma release assays we demonstrate that the NS4.1769 epitope, is generated from natural processing of the NS4 antigen, and presented in the context of the A2/Kb molecules. Interestingly, T cell recognition of the naturally processed form of the NS4.1769 epitope was associated with significant IFN-gamma release, but no direct cytolytic activity. Epitopes of this phenotype might be of interest, in terms of therapy of chronic HCV infection by associating the benefit of localized lymphokine release with low or absent direct cytopathicity.  相似文献   
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The isologous antiidiotypic response in BALB/c mice to immunization with the DNP-binding IgA myeloma protein, MOPC 315, alters the expression of the anti-DNP antibody repertoire and confers immunity against MOPC 315 myeloma tumors. In order to characterize the idiotopes on MOPC 315 IgA which elicit this response we have isolated four monoclonal antiidiotypic antibodies (AIA), D10 (IgG2a), A2(IgG1), G3 (IgG2b) and F1 (IgG2a), produced by splenocytes of BALB/c mice immunized with MOPC 315 IgA in three independent fusion experiments. These AIA react with MOPC 315 IgA. reassociated H315 L315 and F315V but not with free H315, L315, V315H or V3152. In addition the AIA do not react with the closely related DNP-binding IgA myeloma protein, MOPC 460, suggesting that they are directed against private idiotopes on MOPC 315 IgA. These idiotopes can be divided into two groups. Group I, defined by D10, A2 and G3 consists of two overlapping idiotopes, one of which is related to the hapten-binding site. The two idiotopes are formed by an interaction of amino acids in H315 and L315. Group II defined by F1 consists of one idiotope which is related to the hapten-binding site. This idiotope is comprised of an aminoacid sequence on H315 which requires an interaction with either L315 or L460 for expression. A2 and G3 react identically with the same idiotope but were derived from two independent fusion experiments. This indicates an identity of AIA clonotypes among individual mice and suggests that the isologous AIA response to MOPC 315 IgA is restricted.  相似文献   
35.
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   
36.
To develop a model for mold allergen extract standardization, we studied eight commercial Alternaria extracts from various suppliers by a variety of immunochemical and physicochemical techniques, including measurement of Alt-I, a purified allergenic fraction of Alternaria. Wide variations were noted in the allergenic and antigenic potencies of these extracts. Estimates of Alt-I content measured by Alt-I RAST inhibition and by radioimmunoassay correlated significantly (p < 0.05), but Alt-I activity by either method could not be correlated with allergenic potency as measured by RAST inhibition using solid-phase Alternaria. Each test extract produced unique and differing patterns of Coomassie blue-stained bands in isoelectrofocusing gels and in crossed immunoelectrophoresis gels using rabbit antibodies to Alternaria. The optimal method for mold allergen standardization involves a combination of RAST inhibition, isoelectrofocusing, and crossed immunoelectrophoresis techniques, and, if possible, quantitation of individual allergens.  相似文献   
37.
The effect of various immunomodulators on the induction of experimental autoimmune encephalomyelitis (EAE) is evaluated in the Lewis rat. Bordetella pertussis (BP) is the optimal inductor of EAE in this rat strain. Treatment of the animals with BP either before or after or simultaneously with guinea-pig spinal cord preparation (GpSC) resulted in an EAE about two weeks thereafter. Additional injection of living BCG, of CFA, IFA (incomplete Freund's adjuvant) or Vibrio cholerae neuraminidase (VCN) did not augment or mitigate the effect induced by BP or GpSC. Living BCG, IFA, VCN or Corynebacterium parvum (CP) did not induce EAE when given in combination with GpSC but without BP. CFA combined with GpSC only occasionally induced EAE. However, EAE could be induced by the combination of CFA and GpSC or IFA and GpSC in a part of the animals tested if they had been pretreated or simultaneously been injected with living BCG by intravenous route. EAE could not be enhanced by the additional injection of VCN. Surprisingly, most of the animals peracutely died after injection of CFA and BP in combination with GpSC when they had been pretreated with CP. This effect was most pronounced when pretreatment was done on day -4. No acute effect could be seen when CP was given simultaneously to CFA, BP and GpSC. Animals which did not peracutely succumb developed EAE similarly as those in the positive control groups. CP treatment simultaneously with BP but without CFA resulted in a reduction of the EAE specific mortality. This reduction could not be seen if treatment with CP was done after injection of GpSC and BP.  相似文献   
38.
Summary Previous reports by us have shown that the outcome of breast cancer patients who have received systemic adjuvant therapy is influenced by tumor estrogen or progesterone receptor (ER or PR) content or by nuclear grade. This publication provides information regarding the relative merit of those three markers. Findings from patients receiving L-PAM plus 5-FU (PF) or PF plus tamoxifen (PFT) indicate that the disease-free survival and survival within each regimen was almost identical when related to either ER, PR, or nuclear grade. Those having tumors with either of the receptors 10 fmol or a good nuclear grade had a better outcome through five postoperative years than did those with ER or PR 0–9 fmol or poor nuclear grade. The magnitude of the difference was similar for each of the three discriminants. Since they were found to be of equal predictive value, one marker might well serve as a substitute for another. Cox regression analyses, however, clearly indicate that ER, PR, and nuclear grade have an independent influence on outcome and that a more accurate assessment of outcome is obtained when more than one marker is employed. Thus, information should be obtained on as many markers as possible. This conclusion is supported by observations presented which indicate that nuclear grade in combination with either or both of the receptors is a better predictor than either marker alone and that, as indicated by life table probability values and relative odds ratios, an increasing number of favorable tumor prognostic indicators results in a better patient outcome particularly in PFT-treated patients. A possible explanation is considered for why the separation of receptor/nuclear grade categories is more orderly and pronounced in PF-treated patients receiving tamoxifen than in those given PF alone. See Appendix I  相似文献   
39.
目的 在“药辅合一”理念下导入Pickering乳技术,提升儿科用药羚珠散中石菖蒲挥发油的稳定性。方法 对羚珠散各饮片粉末进行初步表征,确定稳定剂。通过成乳量、包油量和乳剂形态筛选出最佳稳定剂质量浓度、油水比和制备方法。并使用近红外光谱(nearinfraredspectroscopy,NIRS)分析石菖蒲油在Pickering乳中的包裹状态。比较不同时间下各组别挥发油的保有量、丙二醛和过氧化物的含量。再通过GC-MS分析其中成分的变化趋势。结果 筛选出珍珠粉作为Pickering乳的稳定剂,珍珠粉质量浓度为65 mg/mL,油水比9∶11为最优成乳条件,高压均质法为最优的制备方法,NIRS分析可知石菖蒲挥发油被珍珠粉包裹,Pickering乳液中没有形成新的化学键。对比各组在不同时间段下石菖蒲油的保有率和其中丙二醛和过氧化物含量,可知40℃放置1、3、8 h的Pickering乳剂相比于石菖蒲挥发油组有更高的保有率和更低的氧化程度。GC-MS分析结果表明,相比于石菖蒲挥发油组,Pickering乳组挥发性成分的稳定性显著提高。结论 在“药辅合一”理念下Pickering乳可用于含油固...  相似文献   
40.
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