共查询到20条相似文献,搜索用时 15 毫秒
1.
Self-sandwich method. An improved immunoperoxidase technic for the detection of small amounts of antigens 总被引:11,自引:0,他引:11
The unlabeled antibody peroxidase-antiperoxidase (PAP) sequence has been widely accepted as the most sensitive method for demonstrating antigens in paraffin sections. However, the results have been unpredictable in routine surgical specimens, with frequent false-negative stains. In order to amplify the staining reactions a self-sandwich method was used. The amplifier (antigen itself) was added after the application of specific antibody. The procedure may be repeated several times before the application of the bridge antiserum followed by PAP complexes. The method was designed to increase the number of antigen-antibody layers without increasing the number of heteroantisera in the system. Specimens derived from routine tonsillectomy were studied semi-quantitatively. Based on the number of positively stained Ig-containing cells in germinal centers, the sensitivity of the self-sandwich method was estimated to be 20 to 50 times that of the PAP method. In addition, extracellular Ig (reticular staining) and surface Ig were also stained positively in the germinal centers and lymphocytic mantles, respectively, but were not demonstrated by the PAP method. The enhancement of the sensitivity was achieved without compromising the specificity. 相似文献
2.
An immunization procedure is presented which enhances the immune respons to weakly immunogenic tumor-specific cell surface antigens by coupling new helper antigens to tumor cells. Mice were immunized with lyophilized tumor cell membranes to which helper antigen was coupled. Only animals which were so primed against the helper antigen as to induce delayed hypersensitivity showed an increased in vitro immune response. This was not found in mice which were not primed or which exhibited immediate hypersensitivity. The possibility is discussed of enhancing immune response by introducing additional helper determinants linked to the original antigens. 相似文献
3.
The red cell mass was measured in 44 normal subjects and showed a closer correlation with total body water or surface area than with body weight. The results obtained in a group of patients with polycythaemia, however, still overlap with the normal range. When the total number of circulating red cells is measured these patients form a group quite separate from the normals. The diagnostic value of this measurement is therefore considerably greater than results obtained with the red cell mass. 相似文献
4.
5.
L P Pertschuk E Gaetjens A C Carter D J Brigati D S Kim T E Fealey 《American journal of clinical pathology》1979,71(5):504-508
Unselected, consecutive surgical specimens from 120 women with cancer of the breast were subjected to histochemical assay for the presence of estrogen receptor. A fluoresceinated bovine serum albumin--estradiol conjugate was used that linked estradiol at position 17 and contained 5 mol fluorescein and 4 mol estradiol per mole albumin. Simultaneous competitive binding studies with excess unlabeled estradiol, diethylstilbestrol, and the antiestrogen nitromifene citrate were regularly performed. Results were compared to those obtained by the dextran-coated charcoal receptor assay. Three specimens were necrotic, two others thawed, and two lacked sufficient protein for biochemical analysis. One specimen did not contain tumor, and 11 others showed a predominant nuclear staining pattern. Nuclear receptor was not assayed biochemically. Comparison of results in the remaining 101 cases showed agreement in 92%. The precedure is uncomplicated, economical, and could be performed and interpreted in any pathology laboratory. 相似文献
6.
A reliable and uniform vascular perfusion fixation method for the testis has been developed by using an initial washout solution containing a vasodilator and an anticoagulant. This is followed by a brief fixation with a sodium phosphate buffered formaldehyde-glutaraldehyde solution of conventional strenght, and then a second more concentrated aldehyde fixative solution containing picric acid. The method takes into account some of the unique features of the vascular supply of the male genital tract for its favorable perfusion and fixation. The advantages of this method are: (1) consistently favorable preservation of the testis; (2) simple and inexpensive apparatus; and (3) stable and relatively innocuous stock solutions. 相似文献
7.
An improved data analysis method for interleukin 2 microassay 总被引:1,自引:0,他引:1
Development of the interleukin 2(IL 2) microassay, coupled with the use of highly purified or recombinant factors has allowed a detailed examination of the mechanism of action of this important biological response modifier. However, probit analysis of the microassay data does not allow inherent error of the system to be approximated nor can units of activity be assessed for significance. A computer program was developed to analyze the validity of each regression line and to generate 95% confidence intervals around each line. This program employs analysis of variance, linear regression analysis and the parallel line assay to fix confidence intervals for each IL 2 unit value. The use of recombinant IL 2 as an immunomodulator in clinical settings warrants a more precise statistical method to evaluate normal fluctuations of this factor than currently in use. The development of such a method is presented here. 相似文献
8.
An improved method for the detection of DNA fragmentation. 总被引:20,自引:0,他引:20
A Facchinetti L Tessarollo M Mazzocchi R Kingston D Collavo G Biasi 《Journal of immunological methods》1991,136(1):125-131
An application of the Southern blot technique is described which permits the detection of DNA fragmentation due to cell death by apoptosis. DNA fragments were isolated from cell suspensions and tissues, separated on agarose gel, transferred by Southern blot and hybridized with a radiolabeled total cellular DNA probe. The application of this procedure to thymus cell samples, revealed the distinct ladder pattern of DNA fragments in multiples of about 180-200 base pairs, a characteristic feature of DNA fragmentation. In comparison to conventional DNA visualization with ethidium bromide staining, the radiolabeled probe improved the detection of DNA fragments at least eight-fold. This method detects low levels of DNA fragments, as well as physiological tissue DNA fragmentation, while avoiding cell damage due to DNA radiolabeling. 相似文献
9.
Chromik J Schnürer E Georg Meyer R Wehler T Tüting T Wölfel T Huber C Herr W 《Journal of immunological methods》2006,308(1-2):77-89
The design and successful clinical implementation of cancer vaccines targeting the induction of T-cell mediated immunity is a rapidly evolving field that is hampered by an empirical selection of antigen and adjuvant. In particular, vaccines using defined tumor-associated peptide epitopes elicit only a restricted T-cell repertoire in a minority of patients. In this regard, vaccines comprising the whole spectrum of antigens presented by individual autologous tumors would be advantageous. In an in vitro model, we evaluated the capacity of naturally processed Epstein-Barr virus-transformed B-lymphoblastoid-cell line (LCL)-derived peptides to activate virus-specific CD8+ T cells of seropositive healthy individuals. While bulk peptides obtained by mild acid elution from LCL contained multiple T-cell epitopes, this complex mixture of peptides was poorly immunogenic, even when presented by mature dendritic cells (DC). Pretreatment of DC with proteasome inhibitors strongly enhanced the immunogenicity of single viral synthetic as well as bulk LCL peptides. This was most likely achieved by facilitating the loading of exogenous epitopes onto DC-associated HLA-class I complexes in the face of significant inter-peptide competition for such loading. Our results suggest that proteasome inhibitors may be used to increase the antigenicity of mature DC pulsed with exogenous synthetic or naturally processed peptide epitopes in vaccination trials. 相似文献
10.
11.
E.L. LAGAAIJ G.F. CRAMER-KNIJNENBURG J.W. VAN DER PIJL J.A. BRUIJN J.W. DE FIJTER & J.H.J.M. VAN KRIEKEN 《Histopathology》1997,31(3):284-288
Aims:
A case report is presented in which an unexpected pathological diagnosis raised the possibility that biopsies of two patients were mixed-up. Since these biopsies were obtained from kidney transplant patients, the HLA-typings of both patients were known.
Methods and results:
We developed an immunohistochemical method using HLA-class I specific monoclonal antibodies to recognize the donor and recipient antigens in these biopsies. Using this method we could confirm the identity of the patients of whom the biopsies had been taken.
Conclusions:
This method, which uses the highly polymorphic HLA-system, is potentially useful for rapid and easy verification of the identity of specimens if a mix-up is suspected. 相似文献
12.
Reliable monitoring of respiration plays an important role in a broad spectrum of applications. Today, there are several methods for monitoring respiration, but none of them has proved to be satisfactory in all respects. We have recently developed a bioacoustic method that can accurately time respiration from tracheal sounds. The aim of this study is to tailor this bioacoustic method for monitoring purposes by introducing dedicated signal processing. The method was developed on a material of ten patients and then tested in another ten patients treated in an intensive care unit. By studying the differences in the variation of the spectral content between the different phases of respiration, the described method can distinguish between inspiration and expiration and can extract respiration frequency, and respiration pause periods. The system detected 98% of the inspirations and 99% of the expirations. This method for respiration monitoring has the advantage of being simple, robust and the sensor does not need to be placed closed to the face. A commercial heart microphone was used and we anticipate that further improvement in performance can be achieved trough optimization of sensor design. 相似文献
13.
A S Slutsky 《Medical hypotheses》1975,1(5):178-182
A new method is proposed for the estimation of infarction size from several measurements of creatine phosphokinase (CPK) activity. This method develops the previous method of Shell and co-workers by introducing the concept of a time- dependent fractional disappearance rate for CPK (kd(t) from the blood. This method would allow more accurate estimates to be made of infarction size. 相似文献
14.
M G Wing A M Montgomery S Songsivilai J V Watson 《Journal of immunological methods》1990,126(1):21-27
A high non-specific background fluorescence signal was observed when cell surface antigen analysis was carried out using flow cytometry on a cell sample which contained a high proportion of dead and dying cells. To overcome this problem it was necessary to analyse the cells in three stages. First the intact cells were identified by their forward (FWD) and 90 degree scatter profile. These cells were gated-on, then analysed on the basis of their FWD scatter and propidium iodide (PI) signal, allowing the dead PI positive cells to be gated out. The PI negative cells were then displayed using their 90 degree scatter and fluorescence signals following staining with the irrelevant antibody control. This revealed a population of dead cells, which despite being PI negative, were non-specifically binding antibody molecules. Such multiparameter analysis permitted the successful analysis of cell surface antigens in preparations of low viability by gating out the high background fluorescence associated with dead PI positive and negative cells. 相似文献
15.
Quantitative culture of Malassezia furfur from clinically healthy skin in 25 individuals was performed with two different methods using contact plates. The best results were obtained when a glucose peptone yeast extract medium, with the addition of milk, Tween-60, glycerol and glycerol monostearate was used. Different techniques for incubation and the reproducibility of this method were evaluated. Incubation can be done in a plastic bag at 32 or 37 degrees C. This new method is simple, the colonies are easy to identify and the counts are high and reliable. 相似文献
16.
We have recently shown that ovalbumin (OVA) entrapped in pH-sensitive liposomes could sensitize mouse thymoma cells for lysis by MHC class I-restricted cytotoxic T lymphocytes (CTL) (Reddy et al. (1991) J. Immunol. Methods, 141, 157-163). The present studies were designed to optimize the antigen delivery system. A simple freeze-thaw method was developed to load OVA into pH-sensitive liposomes, and the protocol was optimized in terms of the choice of buffer, pH and ionic strength of the medium, lipid composition, lipid and OVA concentrations and the number of freeze-thaw cycles. Under optimized conditions, approximately 25% of OVA could be entrapped in pH-sensitive liposomes at 172 micrograms protein/mg lipid. This compares to only about 5% entrapment (70 micrograms protein/mg lipid) using the previous method. OVA loaded to pH-sensitive liposomes using the improved method led to a sensitive measure of CTL activity. The approach promises to be suitable to measure CTL against less available soluble antigens such as viral proteins. 相似文献
17.
W. G. Forssmann S. Ito E. Weihe A. Aoki M. Dym D. W. Fawcett 《Anatomical record (Hoboken, N.J. : 2007)》1977,188(3):307-314
A reliable and uniform vascular perfusion fixation method for the testis has been developed by using an initial washout solution containing a vasodilator and an anticoagulant. This is followed by a brief fixation with a sodium phosphate buffered formaldehyde-glutaraldehyde solution of conventional strength, and then a second more concentrated aldehyde fixative solution containing picric acid. The method takes into account some of the unique features of the vascular supply of the male genital tract for its favorable perfusion and fixation. The advantages of this method are: (1) consistently favorable preservation of the testis; (2) simple and inexpensive apparatus; and (3) stable and relatively innocuous stock solutions. 相似文献
18.
Recent advances in the development of conjugate polysaccharide vaccines for human use have stimulated interest in the use of assays detecting antibody-secreting cells (AbSC) with specificity for bacterial antigens. Here we present improved haemolytic plaque-forming cell (PFC) assays detecting AbSC with specificity for tetanus and diphtheria toxoid as well as for Haemophilus influenzae type b and pneumococcal capsular polysaccharides. These assays were found to be less time consuming, more economical and yielded 1.9-3.4-fold higher plaque numbers than traditional Jerne-type PFC assays. In the case of anti-polysaccharide AbSC of the IgG isotype, the increase was as high as 7.4-11.8 times. Evidence is presented that the pronounced improvement in the detection of the latter is due to the presence of aggregating anti-IgG antibody from the beginning of the assay. It is proposed that in the case of low affinity of anti-polysaccharide antibodies aggregation of secreted monomeric antibody (IgG) is critical for plaque formation and increases the avidity of binding to target cells. 相似文献
19.
An improved method for purification of lymphocytes 总被引:1,自引:0,他引:1
A method that combines glass-bead column filtration, Ficoll-Hypaque gradient separation, discontinuous sucrose gradient, and drastic reduction of cell transfers is described. The procedure gives a high yield of pure human lymphocytes from small amounts of blood, good preservation of B cell/T cell ratio, and sufficient material for subsequent biochemical studies. 相似文献
20.
Nippa JH 《Journal of clinical engineering》1980,5(2):157-160
First generation EMI head scanners have a poor image display and photography system. This paper describes how an image converter is interfaced to the EMI viewer console to produce a standard television image. The design also incorporates a multi-image photography unit to allow photographing of up to nine images on one standard X-ray film. The converted system's advantages are: a bright and stable display, reduced operator time, and significant material savings. 相似文献