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排序方式: 共有6270条查询结果,搜索用时 15 毫秒
101.
Sinuhe Hahn Thomas Stalder Marion Wernli Diana Bürgin Jürg Tschopp Shigekazu Nagata Peter Erb 《European journal of immunology》1995,25(9):2679-2685
Fas was recently demonstrated to be the major target molecule engaged by CD4+ cytolytic T lymphocytes (CTL). We examined Fas expression on various cloned T cell subpopulations and their susceptibility to lysis by CD4+ or CD8+ CTL. A reciprocal relationship in Fas and Fas-ligand expression was observed in CD4+ T helper (Th)1- and Th2-type clones, and Fas mRNA was predominantly detected in Th2 clones, whereas Fas-ligand mRNA was principally found in Th1 clones. The two Th0 clones tested expressed both Fas and Fas-ligand, but only one exhibited cytolytic activity, whereas both were sensitive to CD4-mediated lysis. A functional consequence of the inverse Fas-Fas-ligand expression pattern was that Th2 and Th0 cells were sensitive to lysis by both Th1 CD4+ CTL and a CD8+ CTL clone in a Fas-dependent manner. These results suggest that cytolytic CD4+ Th1 cells may play an immunomodulatory role, regulating a Th2/Th0 response by Fas-mediated lysis. 相似文献
102.
慢性乙肝患者杀伤性免疫细胞功能的研究 总被引:8,自引:0,他引:8
通过对44例病毒性肝炎患者T细胞亚群,NK细胞活性与LAK细胞活性的观察,探讨了在慢性乙型肝炎病毒复制与非复制状态下的杀伤性细胞活性。结果表明:在乙肝病毒的高复制状态下,CD8^+细胞数增加,CD4^+/CD8^+比例显著下降;NK细胞活性与LAK细胞活性也明显低下,且在HBeAg与HBVDNA阳性组中,NK活性与LAK活性的改变与HBeAg的P/N值变化呈显著负相关,而NK活性与LAK活性变化则 相似文献
103.
Donald G. Payan L. Joseph Wheat Zackarie Brahmi Stephen Ip W. Peter Hansen Robert A. Hoffman Kathleen Healey Robert H. Rubin 《Journal of clinical immunology》1984,4(2):98-107
Circulating T-lymphocyte subpopulations were enumerated in 65 patients with histoplasmosis and correlated with the different clinical manifestations of the disease. Acute pulmonary histoplasmosis, rheumatologic, disseminated, and chronic inflammatory manifestations of histoplasmosis were all associated with a significant elevation above normal of OKT8+ (suppressor-cytotoxic) lymphocytes and a significantly lower than normal OKT4+ (helper-inducer)-lymphocyte to OKT8+-lymphocyte ratio. In contrast, cavitary disease was associated with an increase in OKT4+ lymphocytes, a decrease in OKT8+ lymphocytes, and a higher than normal OKT4/OKT8 ratio. Clinical recovery was associated with normalization of these values. Functional activity determined by coculture techniques correlated closely with T-lymphocyte subset measurements. These distinct subset abnormalities may help monitor immunological aspects of disease activity. 相似文献
104.
Flow cytometric analysis of cell proliferation dynamics in the B cell compartment of the mouse 总被引:20,自引:0,他引:20
Using a method which allows simultaneous flow cytometric detectionof cell surface markers and 5-bromo-2'-deoxyuridine (BrdU) incorporation,the distribution and proliferative behavior of B lineage subpopulationswas studied in intact adult mice. In the bone marrow we coulddefine two subsets of B cells on the basis of differential expressionof the pan-B cell marker B220 and of membrane-associated µand immunoglobulin heavy chains. B220dullµ+– Bcells were found to emerge from rapidly dividing cells and probablyrepresent B cells recently generated from B220dullµ–pie-B cells. In contrast, oniy few, If any, of the B220brightµ++B cells were labeled with BrdU after a period of 8 days, suggestingthat these cells represent long-lived B cells residing in thebone marrow. Analysis of BrdU-Incorporation into splenic B cellsshowed that only 20% of these cells had gone through cell divisionduring the preceding 8 days. Almost none of the B cells in theperitoneum, a large fraction of which belongs to the Ly1 B subset,were labeled with BrdU over a period of 7 days in 8-month-oldanimals. 相似文献
105.
Westerholm-Ormio M Garioch J Ketola I Savilahti E 《Clinical and experimental immunology》2002,128(1):94-101
T helper cell type 1 (Th1) response to gluten has been implicated in the pathogenesis of coeliac disease (CD). To characterize immunological activation and mild inflammations leading to overt CD in potential coeliac patients, jejunal biopsies were obtained from family members of patients with CD or dermatitis herpetiformis (DH). Nine family members and one latent CD, eight CD patients and eight normal controls furnished jejunal biopsy specimens. Immunohistochemical staining of sections for interleukin-1alpha (IL-1alpha), IL-2, IL-4, interferon-gamma (IFN-gamma), tumour necrosis factor alpha (TNF-alpha), CD3, gammadelta-T cell receptor (gammadelta-TCR), and alphabeta-TCR was carried out with monoclonal antibodies. Further, expression of IL-4 and IFN-gamma messenger RNA was detected by radioactive in situ hybridization in these same samples. In lamina propria, CD patients and potential CD patients had higher densities of IL-2 (P = 0.028, P = 0.043), IL-4 (P = 0.021, P = 0.034) and IFN-gamma positive cells (P = 0.000, P = 0.009) than did controls. Moreover, CD patients showed a higher density of TNF-alpha positive cells (P = 0.012, P = 0.001) than the other two groups, and expression of IFN-gamma mRNA (P = 0.035) was higher in them than in the other two study groups. Additionally, higher densities of TNF-alpha and IFN-gamma positive cells occurred in potential CD patients with high gammadelta-TCR+ intraepithelial lymphocytes (IELs). Our findings support the hypothesis that lamina propria T cells and macrophages, through their secretion of cytokines, play a central role in the pathogenesis of coeliac disease. The inflammatory cytokines found in potential CD specimens strongly suggest that these inflammatory markers can be identified long before visible villous changes have occurred. 相似文献
106.
目的:探讨了冠心病患者治疗前后血清SOD、ET及T淋巴细胞亚群水平。方法:分别应用放免法和单克隆抗体法对42例冠心病患者进行了血清SOD、ET及T淋巴细胞亚群水平检测,并与35名正常健康人作比较。结果:冠心病患者在治疗前血清ET水平显著地高于正常人组(P<0.01),而SOD和CD4/CD8比值明显地低于正常人组(P<0.01),经治疗后一个月则与正常人组比较差异无显著性(P>0.05)。结论:检测冠心病患者血清SOD、ET及T淋巴细胞亚群水平对判断病情及其预后均具有一定的临床实用价值。 相似文献
107.
Elli Ioachim-Velogianni Nickolaos E. Stavropoulos Evangelia Kitsiou Stella Stefanaki Niki J. Agnantis 《The Journal of pathology》1994,174(3):183-189
Lymphocyte subpopulations (B cells, CD4, CD8), interleukin-20 receptors (IL-2), monocytes/macrophages (Leu M5), and HLA-DR antigen expression were studied immunohistochemically on frozen sections from 38 bladder cancer specimens. T cells predominated over B cells in all tumours. CD4-positive lymphocytes predominated over CD8 in the stroma (CD4/CD8: 1·35/1), while in epithelial tumour cells CD8 was the prominent subpopulation (CD8/CD4: 1·75/1). Aberrant HLA-DR expression was found in 21·05 per cent of bladder tumours. A strong correlation between CD4 and CD8 population densities and macrophages with the other subpopulations was noticed. In HLA-DR-positive tumours, there was no correlation of the percentage of positive cells with CD4- and CD8-positive lymphocyte populations. Various parameters including IL-2 receptors, B cells, CD8- and CD4-positive cells, and macrophages did not differ significantly between the groups of tumours expressing and not expressing HLA-DR antigen. There were no statistically significant differences in the population densities of B cells, CD8- or CD4-positive cells, IL-2 receptor, monocytes/macrophages, and HLA-DR antigen expression among various clinicopathological parameters, including growth pattern, histological grade and clinical stage or patient's age and sex. These findings suggest that in transitional cell carcinoma of the urinary bladder, HLA-DR antigen expression is independent of lymphocyte subpopulations. It is therefore possible that HLA-DR expression by tumour cells reflect the existence of separate HLA-DR-positive or HLA-DR-negative tumour clones. 相似文献
108.
NOD鼠胸腺及外周淋巴细胞亚群变化与年龄关系 总被引:1,自引:0,他引:1
NOD鼠可自发地患糖尿病,该鼠的发病与自身免疫性淋巴细胞对胰岛的浸润,从而引起胰岛β细胞的不断破坏有关。这种破坏可能是由T淋巴细胞所引起的。雌性NOD鼠胸腺及外周淋巴细胞随年龄的增加胸腺细胞数量减少而脾细胞数量增加。用CD4/CD8双抗双标检测显示,雌性NOD糖尿病鼠胸腺双阴性与单阳性细胞的比例增加而双阳性细胞的比例减少。外周CD4比CD8阳性细胞的比值在胰岛炎期增高,在糖尿病期下降。 相似文献
109.
Lymphocyte proliferation in response to acute heavy resistance exercise in women: influence of muscle strength and total work 总被引:3,自引:0,他引:3
Dohi K Mastro AM Miles MP Bush JA Grove DS Leach SK Volek JS Nindl BC Marx JO Gotshalk LA Putukian M Sebastianelli WJ Kraemer WJ 《European journal of applied physiology》2001,85(3-4):367-373
Little is understood about the immune responses to heavy resistance exercise. The purpose of this investigation was to determine
the influence of physical strength and the ability to do more total work on lymphocyte proliferation after an acute bout of
heavy resistance exercise. A group of 50 healthy but non-strength trained women were recruited for the study and tested for
their one repetition maximum (i.e. 1 RM or maximal mass lifted once). From the normal distribution of strength the top and
bottom 8 women [mean age 22.5 (SD 3.1) years] were asked to volunteer to define our two groups (i.e. high strength and low
strength). The two groups were significantly different (P<0.05) in 1 RM squat strength [low strength 39.9 (SD 4.6) kg, 0.65 (SD 0.08) kg·kg body mass–1 and high strength 72.2 (SD 10.7) kg, 1.1 (SD 0.12) kg·kg body mass–1] but were not significantly different in body mass, age, activity levels, and menstrual status (all in same phase). Each
performed a resistance exercise protocol consisting of six sets of 10 RM squats with 2 min rest between the sets. The 10 RM
loads and total work were significantly greater in the high strength group than in the low strength group. Blood samples were
obtained pre-exercise and immediately post-exercise for test for lactate (significant increase with exercise) and cortisol
(no changes) concentrations with no differences noted between groups. Immunological assays on the blood samples determined
the incorporation of tritiated thymidine by lymphocytes in responses to concanavalin A (ConA), phytohemagglutinin (PHA), and
pokeweed mitogen (PWM). Following the squat exercise, there was a significant decrease in lymphocyte responsiveness to PWM
in the high strength but not in the low strength group for both total proliferation and proliferation adjusted per B or T
cell. On the other hand, lymphocytes from the low strength group proliferated to a significantly greater extent (adjusted
per T cell) in response to ConA and PHA. These data indicate that the heavy resistance exercise protocol reduced the lymphocyte
proliferative responses only in the stronger group of subjects. This effect may have been due to the high absolute total work
and the greater exercise stress created by the resistance exercise protocol in the high strength group. Therefore, individuals
performing at the same relative exercise intensity (i.e. 10 RM) in a resistance exercise protocol may have different immune
responses stemming from differences in absolute total work performance.
Electronic Publication 相似文献
110.
Silvano Ferrini Anna Cambiaggi Raffaella Meazza Sabrina Sforzini Sabrina Marciano Maria Cristina Mingari Lorenzo Moretta 《European journal of immunology》1994,24(10):2294-2298
A new anti-p58 monoclonal antibody (mAb), termed CH-L, has been used to characterize a minor subset of T lymphocytes co-expressing p58 and CD3 molecules. In two-color immunofluorescence analysis, CH-L+CD3+ cells represented 0.5 to 6% of the peripheral blood lymphocytes (in 20 healthy donors). Clonal analysis showed that most CD3+CH-L+ T cell clones expressed the CD8+4? T cell receptor (TcR) α/β+ phenotype, while only a few were CD8?4+ TcR α/β+, CD8?4? TcR α/β+ or CD8?4? TcR γ/δ+. Western blot analysis indicated that the CH-L mAb identifies the same 56-58-kDa diffuse band in both T and natural killer cell (NK) clones. A minority of T cell clones also expressed other NK-related markers such as CD16, CD56 and CD94 and two clones also reacted with the anti-p58 mAb EB6. Interestingly, most clones displayed cytolytic activity in an anti-CD3 mAb-triggered redirected killing assay against the Fcδ receptor+ P815 target cells and NK-like activity against K562 and Raji cells. In contrast, the IGROV-1 ovarian carcinoma cell line was resistant to cytolysis by all of these clones. Since p58 molecules have previously been shown to exert regulatory functions on NK-mediated lysis, we investigated whether anti-p58 mAb could also influence cytotoxicity mediated by CD3+p58+ T lymphocytes. Lysis of P815 target cells, triggered by anti-CD3 mAb, could be inhibited by anti-p58 mAb in 8 out of 12 cytolytic clones tested, while 4 clones were not inhibited. In addition, anti-p58 mAb enhanced the cytolytic activity of 3 clones against IGROV-1 and of 4 other clones against Raji target cells. Taken together, these data indicate that p58+ T cells express heterogeneous phenotypes and different forms of TcR and, in most instances, display cytolytic functions. Perhaps more importantly, the p58 molecule appears to modulate the cytolytic activity triggered via the CD3/TcR complex. 相似文献