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991.
小鼠ARS腹水型网状细胞肉瘤瘤株加1.5、2.0、2.5%DMSO体外培养,被诱导出现了巨噬细胞样分化。细胞及核缩小,尤以核缩小为著,核质比值下降。2.5%DMSO的作用最显著,核仁缩小仅见于2.5%组。核质比值小于0.5,且核仁亦缩小的细胞近似巨噬细胞。2.5%DMSC使非特异性酯酶阳性细胞增多;Po1ystyrene胶乳颗粒吞噬百分数和吞噬指数亦增高。透射电镜观察,2.5%DMSO处理的、核质比值小于0.5的ARS细胞内,细胞器丰富,Golgi复合体发达,次级溶酶体增多。扫描电镜观察,对照组的大细胞多,表面有多数密集的细长微绒毛。2.5%DMSO处理的ARS,大细胞减少,小细胞增多,微绒毛明显缩短减少。这种小细胞与光镜和透射电镜下观察的小细胞一致,是分化程度较高的巨噬细胞样细胞。2.5%DMSO处理的ARS细胞核分裂指数显著下降。 相似文献
992.
Nicolai S.C. van Oers Soo-Jeet Teh Bryan A. Irving Jacqueline Tiong Arthur Weiss Hung-Sia Teh 《Journal of immunological methods》1994,170(2):261-268
The T cell receptor (TCR) comprises an antigen-specific β heterodimer non-covalently associated with the CD3 γδε and TCR ζ subunits. Both the CD3 and TCR ζ subunits are proposed to be responsible for the intracellular signal-transduction events. We report here the production of eight monoclonal antibodies (mAbs) that bind in an ELISA assay to a 113 amino acid synthetic peptide corresponding to the cytoplasmic domain of TCR ζ. Western blot analysis of anti-CD8 precipitates of lysates of transfectants expressing chimeric CD8/ζ constructs encoding increasing COOH-terminal truncations of TCR ζ indicates that four of these mAbs recognized the region of TCR ζ chain comprising the last 29 COOH-terminal residues. Thus, this region of TCR ζ may encode an immunodominant epitope. Furthermore, one of these mAbs, G3, is capable of precipitating both non-phosphorylated and tyrosine phosphorylated TCR ζ. The G3 mAb should be useful for elucidiating the structural and signalling characteristics of the TCR ζ chain. 相似文献
993.
K G Chandy M A Charles B Buckingham N Waldeck A Kershnar S Gupta 《Immunology letters》1984,8(2):89-91
Peripheral blood from 11 newly diagnosed patients with insulin-dependent diabetes mellitus (IDDM) was studied for the proportion of monoclonal antibody (HNK 1, Leu 7) defined natural killer (NK) cells using a fluorescence-activated cell sorter analyzer. The proportion of Leu 7+ cells in patients with IDDM (7.0 +/- 4.0) was significantly (P less than 0.001) lower than in simultaneously studied healthy controls (16.8 +/- 7.0). A 2-yr-old boy with recent onset IDDM had a deficiency of Leu 7+ NK cells (6.1%), while his healthy identical twin had normal proportions of Leu 7+ cells (22.2%), when compared to a simultaneously studied healthy control. Two patients reexamined in remission and one other studied in remission alone, showed deficiency of Leu 7+ NK cells. This study demonstrates a quantitative deficiency of monoclonal antibody (Leu 7+) defined NK cells in newly diagnosed patients with IDDM that persists during remission of the disease and therefore appears to be independent of metabolic abnormality. The deficiency of NK cells may predispose genetically susceptible individuals to viral-induced islet cell injury, contributing to the pathogenesis of IDDM. 相似文献
994.
Surface markers of human natural killer cells as analyzed in a modified single cell cytotoxicity assay on poly-L-lysine coated cover slips 总被引:2,自引:0,他引:2
A modified single cell cytotoxicity assay using poly-L-lysine coated cover slips (PLL-SCCA) was employed to study the frequency and surface marker profile of human peripheral blood lymphocytes (PBL) with NK reactivity against K 562 target cells. When compared with the previously described agarose single cell cytotoxicity assay (A-SCCA) identical results were obtained. For 13 donors tested 18.1 +/- 4.4% of the PBL formed conjugates with K 562 and 2.7 +/- 1.6% displayed NK reactivity. In contrast to the A-SCCA, the PLL-modified assay permits direct identification of both conjugate forming (TBC) and cytolytic PBL (NK) by means of surface markers. Indirect immunofluorescence studies with monoclonal anti-PBL antibodies revealed that neither the plating procedures nor the incubation conditions employed affected the expression of the antigens recognized by these reagents. This method of directly identifying NK cells showed that OKM1+ cells were enriched among the NK cells as compared to PBL and TBC (55% vs. 23% and 43%, respectively). In contrast, the OKT3+ or Leu1+ fraction of the NK cells was reduced as compared to PBL and TBC. However, using this method of identification at the effector cell level, a substantial proportion of the NK cells were OKT3+ or Leu1+ (57% or 58% respectively, 7 donors). Approximately 25% of the NK cells were Leu2a+ and 30% were Leu3a+, respectively. However, the size of the Leu3a+ fraction varied considerably with individual donors and the size of this fraction appeared to be inversely related to that of the donors NK pool. 相似文献
995.
Induction of immunoglobulin-secreting cells from human peripheral blood lymphocytes in a serum-free culture medium was studied. Albumin, transferrin, insulin and fibronectin can replace serum entirely for support of pokeweed mitogen (PWM)-stimulated B lymphocytes, measured by a reverse hemolytic plaque assay using protein A-coated red cells. In this serum-free system, growth and maturation to IgM and IgG secretion occur at the same or higher efficiency as in conventional serum-containing medium, with maximum numbers of plaque-forming cells on day 6 at optimal dose of PWM, 0.5 ~ 5 μg/ml. This system can be used to avoid the interference from undefined serum components. 相似文献
996.
Dendritic cell number is related to IL-4 expression in the airways of atopic asthmatic subjects 总被引:3,自引:0,他引:3
Bertorelli G Bocchino V Zhou X Zanini A Bernini MV Damia R Di Comite V Grima P Olivieri D 《Allergy》2000,55(5):449-454
BACKGROUND: Airway dendritic cells are essential for stimulating naive T cells in response to inhaled antigen and for the development of allergic sensitization. IL-4 in vitro can distinguish dendritic cell lines from peripheral blood mononuclear cells. Our study had the following aims: 1) to compare the distribution of CD1a+ dendritic cells and IL-4+ cells, in the bronchial mucosa of asthmatics and controls 2) to determine the relationship between the numbers of CD1a+ dendritic cells and IL-4+ cells in the bronchial mucosa of asthmatics 3) to determine whether CD1a+ cells express the IL-4 receptor. METHODS: Twenty atopic asthmatic and eight normal subjects were studied. In each subject, bronchoscopy with bronchial biopsies was performed. CD1a, IL-4, and IL-4 receptor expressions were evaluated by immunohistochemistry. RESULTS: The number of CD1a+ and IL-4+ cells was significantly higher in asthmatics than controls. The number of CD1a+ cells was positively correlated to the number of IL-4 + cells. Bronchial biopsy serial section studies showed that CD1a+ cells express the receptor for IL-4. CONCLUSIONS: These results suggest that an increased amount of IL-4 may play a physiopathologic role in maintaining the dendritic cell pool in vivo. Therefore, because of possible IL-4 activity on antigen-presenting cells in T-cell immune responses to allergens, an important new role of IL-4 in asthma inflammation can be envisaged. 相似文献
997.
Increased phagocytic capacity of the blood,but decreased phagocytic activity per individual circulating neutrophil after an ultradistance run 总被引:3,自引:0,他引:3
Holger Gabriel Hans-Josef Müller Karin Kettler Lars Brechtel Axel Urhausen Wilfried Kindermann 《European journal of applied physiology》1995,71(2-3):281-283
The effect of a long strenuous endurance exercise on the phagocytic function of neutrophils was examined. 9 athletes [7 males, 2 females, age: 36–68 years, body mass: 64 (SD 10) kg, height: 175 (SD 10) cm] completed a competetive 100 km run in 8:07 (median value; range: 7:29–9:50 hours). In a whole blood assay the phagocytosis of opsonized E. coli, the receptor density of the Fc receptor 3 (CD16) and the complement receptor 3 (CD11b, direct immunofluorescence) of neutrophils were measured on a per cell basis by flow cytometry before and up to 3 hours after the race. The phagocytic rate (percentage of neutrophils incorporating bacteria) was unchanged after exercise, whereas the phagocytic activity (number of incorporated bacteria per cell) was significantly reduced by –34 (SD 8) % (Wilcoxon test, P<0.001). The total phagocytic capacity of the blood increased 2-3fold post exercise. The surface antigen expressions of CD11b and CD16 were unaffected by the ultradistance run. The results indicate either a reduced phagocytic function of neutrophils on a single cell basis or the mobilization of neutrophils of the marginal pool with a lower phagocytic activity. However, after a long endurance exercise the phagocytotic capacity of the blood was enhanced due to increased cell concentrations. 相似文献
998.
V. E. Gould K. J. Bloom W. W. Franke W. H. Warren R. Moll 《Virchows Archiv : an international journal of pathology》1995,425(6):617-629
A total of 291 enlarged lymph nodes showing a range of reactive-inflammatory processes, primary and metastatic neoplasms were studied to determine the distribution and immunoprofile of their cytokeratin-positive interstitial reticulum cells (CIRC) in comparison with normal nodes. In 258/291 nodes (89%), CIRC numbers were distinctly increased in the subcapsular, paracortical and, occasionally, in the medullary zones; often, these increased CIRC formed networks around follicles, sinuses and vessels. CIRC had comparatively small, irregularly shaped bodies and dendritic processes; occasionally, giant forms were noted. CIRC contained cytokeratins (CK) 8 and 18 but not 19, as shown by immunohistochemistry, and by gel electrophoresis with subsequent immunoblotting. They co-expressed vimentin consistently, alpha-smooth-muscle actin frequently, and desmin less frequently. They did not contain desmoplakins, Factor VIII, S-100, LCA, B and T lymphocyte- and macrophage-associated antigens, chromogranin A, synaptophysin or the A-80 glycoprotein. We found no clear correlation between the increased CIRC and given nodal disease processes. However, CIRC were most abundant in nodes free of but draining malignant tumours; bizarre CIRC assemblies were noted in HIV lymphadenopathy. CIRC appear to represent a subset of the so-called fibroblastic reticulum cells of lymph nodes. Their function remains undetermined; their increase in diverse lymphadenopathies suggests that they partake in nodal reactions to injury. It remains unclear whether the increase in CIRC relative number is due to proliferation or to CK gene induction processes but their presence and potential capability to undergo hyperplasia with dysplastic forms should alert pathologists to possible diagnostic pitfalls. In addition, we discuss that CIRC may undergo transformation and represent the cell of origin of certain CK-positive tumours restricted to lymph nodes. 相似文献
999.
Sazuku Nisitani Takeshi Tsubata Masao Murakami Tasuku Honjo 《European journal of immunology》1995,25(11):3047-3052
Activation mechanisms of B-1 (Ly-1 B) cells have been suggested to be different from those of conventional B cells. To assess the role of various interleukins (IL) in the activation of B-1 cells, we injected IL-4, IL-5 or IL-10 into nonanemic anti-red blood cells (RBC) autoantibody-transgenic mice, in which conventional B cells are clonally deleted but peritoneal B-1 cells persist without secreting Ig. Intraperitoneal or intramuscular injection of IL-5 or IL-10, but not IL-4, increased the number of antibody-producing peritoneal B-1 cells by four- to five-fold, resulting in increased anti-RBC serum autoantibody and induction of hemolytic anemia. These results suggest that IL-5 or IL-10 may play an important role in the terminal differentiation of B-1 cells into antibody-producing cells in vivo. 相似文献
1000.
Conventional indirect haemagglutination test was performed in rhesus monkey sera (collected from Plasmodium knowlesi infected animals) with and without prior treatment of sera with 2-mercapto-ethanol (2-ME). Surprisingly, many sera samples showed significant enhancement of final titre with 2-ME. The 2-ME enhancement effect was more pronounced in the sera of hyperimmune monkeys on further injection of antigen or parasites. It was also noticeable in the sera during primary drug-suppressed P. knowlesi infection and appeared to have a bearing on the immune status of the animals to rechallenge. The use of a soluble antigen prepared from P. knowlesi infected erythrocytes was found to be essential in IHA test to demonstrate the 2-ME enhancement effect. Antigen prepared from freed parasites (commonly used) failed to show a similar effect in IHA. The possible role of certain T-lymphocyte products - antigen binding, non-agglutinating, 2-ME sensitive molecules - in malarial immunology has been proposed. 相似文献