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921.
目的:探讨CD44v6蛋白表达与胰腺癌增殖及淋巴结转移的关系。方法:应用免疫组织化学(S-P)法检测38例胰腺癌组织标本中CD44v6和PCNA的表达。结果:CD44v6在胰腺癌中的阳性率为65%(25/38),与淋巴结转移呈非常显相关(P<0.01),与胰分化程度无关(P>0.05)。CD44v6阳性染色胰腺组织中PCNA标记率较阴性高(P<0.05)。结论:CD44v6在胰腺癌的增殖,转移过程中可能起重要作用,可作为胰腺癌预后预测的生物学指标之一。 相似文献
922.
The aim of this study was to quantify and characterise the CD4+ and CD8+, CD45RA+, CD45RO- T-lymphocytes that paradoxically expressed the CD29 bright+ phenotype in health and in rheumatoid arthritis. We further evaluated their clinical implications. Blood samples were obtained from 100 patients with rheumatoid arthritis and 40 age- and sex-matched controls. Cell surface antigens and interleukin-2 (IL-2) binding were detected on CD4+ and CD8+ peripheral blood T-lymphocytes (T-PBL) by three-colour flow cytometry. One-third of the patients were clinically evaluated at the time of blood sampling. In healthy donors, we found 16 ± 14% of CD29 bright+cells among CD4+, CD45RA+, RO-T-PBL. These false naive CD4+ T-PBL were Leu-8+, and a majority expressed the CD25/p55 receptor (IL-2R chain), while a minority showed the CDlla bright+, CD69+ and/or CD 122/p75+ (IL-2R chain) phenotype, and few cells were CD31 bright+ and HLA-DR+. In rheumatoid arthritis, their proportion among CD4+, CD45RA+, RO- cells increased to 25 ± 15% (P < 0.001, compared with controls). In patients, the reductions in CD31 and CD38 expression (P < 0.05 for both), as well as the enhanced CD25 expression (P < 0.001) on CD4+, CD45RA+, RO- T-PBL reflected a more differentiated phenotype. The occurrences of CD25 and CD122 were increased on false naive CD4+ T-PBL (0.01 <P<0.001); however, the binding of IL-2 remained very low (in contrast to the binding of IL-2 on CD45RO+ T-PBL). Furthermore, a major subset of CD8+, CD45RA+, RO- T-PBL (45 ± 17% in controls) expressed the CD29 bright+ phenotype. These false naive CD8+ T-PBL included a great many of CID 1lb+, CD28- cells, while a minority showed the HLA-DR+, CD69+ and/orCD122+ phenotypes. Patients with low levels of IgM rheumatoid factors (IgM-RF; but with active disease) had an elevated proportion of CD45RA+, RO-cells among the CD8+ T-PBL, in part due to an increased proportion of false naive cells (P < 0.05). In patients, the false naive CD8+ T-PBL showed down-regulated CD1lb and an increased expression of IL-2 receptor chains (CD25 and CD 122; 0.05 <P < 0.01), but without a significant increase in IL-2 binding. More CD69 on false naive CD8+ T-PBL was found in patients with high levels of IgM-RF (P < 0.005 compared to patients with low 19M-RF). Finally, both false naive CD4+ and CD8+ T-PBL correlated with the clinical process and outcome variables (0.05 <P <0.01). The levels of activated false naive CD4+ T-PBL (CD25+ and/or CD122+) or CD8+ T-PBL (CD69+ and/or CD122+) were associated with clinical parameters of disease activity (0.05 <P < 0.01). Thus, in rheumatoid arthritis, false naive T-PBL showed important qualitative differences. The levels of activated false naive T-PBL could be particularly interesting for monitoring disease evolution. 相似文献
923.
Macey Hou Milne Parameswaren Howe Cavenagh Howells & Newland 《British journal of haematology》1998,101(1):78-81
The platelet-type thrombin receptor was the first member to be identified in a family of protease activated receptors (PARs) and has been designated PAR-1. We recently reported that the large granular lymphocytes (LGLs) in patients with proliferations of CD8+ cells co-expressed PAR-1 and the expression of PAR-1 correlated with the expression of CD57. Here we show, by three-colour immunofluorescence, that the LGLs from a patient with a rare CD4+ CD57+ monoclonal expansion also expressed PAR-1. Northern blot analysis confirmed the presence of high levels of mRNA for PAR-1 in these LGLs. 相似文献
924.
Miyakawa R Ichida T Yamagiwa S Miyaji C Watanabe H Sato Y Yokoyama H Tsukada C Ishimoto Y Sugahara S Yang XH Abo T Asakura H 《Journal of gastroenterology and hepatology》2005,20(7):1126-1130
The human liver contains significant numbers of innate immune cells, such as natural killer (NK) cells and natural killer T (NKT) cells, which express both T-cell receptors and NK-cell receptors simultaneously. It has been suggested that the innate immune system plays a crucial role in the liver. In this report, the distribution of NK and NKT cells in the liver and peripheral blood of two patients with drug-induced fulminant hepatic failure (FHF) who had undergone living donor liver transplantation was examined. In both the liver and peripheral blood, the proportions of NK and NKT cells markedly decreased compared with those in healthy donors. It was also revealed that, unlike murine NKT cells, human CD56(+) T cells and CD57(+) T cells did not constitutively express CD28, which is one of the important costimulatory molecules on T cells. Additionally, the residual CD56(+) T cells and CD57(+) T cells in the patients expressed more CD28 than in controls. This result suggests that NKT cells might be more activated in FHF. Although the accumulation of further cases is required, it is suggested that both NK and NKT cells might be involved in hepatic injury in FHF. 相似文献
925.
Expression and clinical significance of CD44V5 and CD44V6 in resectable colorectal cancer 总被引:16,自引:0,他引:16
Vizoso FJ Fernández JC Corte MD Bongera M Gava R Allende MT García-Muñiz JL García-Morán M 《Journal of cancer research and clinical oncology》2004,130(11):679-686
Purpose This study was conducted to evaluate the prognostic significance of CD44v5 and CD44v6 in resectable colorectal cancer.Materials and methods Membranous CD44v5 and CD44v6 levels were measured by an immunoenzymatic assay in tumors and surrounding mucosal samples obtained from 105 patients with resectable colorectal carcinomas.Results There were no significant differences of CD44v5 levels between tumors [median: 3.2 (range: 0.9–83.5) ng/mg protein) and surrounding mucosal samples (3 (3–146.2) ng/mg protein]. However, tumor samples showed significantly higher CD44v6 levels [19.5 (2.2–562.9) ng/mg protein] than mucosal samples [5 (5–230) ng/mg protein] (P=0.0001). Patients with higher CD44v5 or CD44v6 content in tumor samples had a considerably shorter relapse-free survival (P<0.05, for both). Patients with a higher CD44v6 content also had a shorter relapse-free and overall survival in the multivariate analysis (P<0.05).Conclusion The results of this study suggest a role of CD44v5 and CD44v6 in colorectal cancer progression. Membranous CD44v levels in primary tumors, measured by immunoenzymatic assay, may contribute to a more precise prognostic estimation in patients with resectable colorectal cancer.Supported by grants from ISCIII Red de Centros de Cancer RTICCC (C03/10) and Obra Social Cajastur 相似文献
926.
Lin PC Lee MY Lin JT Hsiao LT Chen PM Chiou TJ 《International journal of hematology》2008,87(4):434-439
CD34+-selected peripheral blood progenitor cells (PBPCs) may not only reduce contaminated tumor cells but also compromise immunologic
reconstitution and increase incidence of infections after transplantation. We analyzed the incidence of virus reactivation
in CD34+-selected PBPCs autologous transplantation. From December 2001 to December 2004, ten high-risk aggressive non-Hodgkin’s lymphoma
(NHL) patients were enrolled in a program of high-dose chemotherapy plus autologous CD34+-selected PBPCs support. Viral screening studies, including clinical symptoms, physical examinations, hepatitis B virus (HBV)-DNA,
cytomegalovirus (CMV)-polymerase chain reaction (PCR), rapid diagnosis of fluorescent antibody stain for herpes-simplex virus
(HSV), and viral culture from blood, fluid or tissue were performed weekly during the first 3 months and then monthly for
1 year. Two of four patients (50%) who were HBV carriers developed HBV reactivation. The other two HBV carriers who received
prophylactic lamivudine therapy did not develop HBV reactivation. Two patients (20%) developed cytomegalovirus (CMV) infection,
and three patients (30%) developed HSV infection in total ten serum-positive patients. The possibility of virus reactivation
might increase in NHL patients undergoing autologous CD34+-selected PBPC transplantation. Administering prophylactic antivirus therapy and closely following patient’s clinical viral
complications should be considered. 相似文献
927.
Ciesek S Liermann H Hadem J Greten T Tillmann HL Cornberg M Aslan N Manns MP Wedemeyer H 《Journal of viral hepatitis》2008,15(3):200-211
Dendritic cells (DCs) play a central role in antiviral immunity. Conflicting data on DC function have been reported for hepatitis C virus (HCV) infection. In addition to antigen presentation and cytokine secretion, a subset of human DCs displays direct cytotoxic activity. It has been suggested that measles virus and human immunodeficiency virus (HIV) may enhance cytotoxicity of DCs potentially leading to apoptosis of activated T cells and subsequent down-regulation of antiviral immune responses. We demonstrate that CD1c-positive myeloid DCs, but not BDCA-4-positive plasmacytoid DCs, are able to kill different target cells mainly via tumour necrosis factor-related apoptosis-inducing ligand. The ability of CD1c+ DCs to lyze target cells was found to be completely impaired in patients with chronic hepatitis C (10 chronic HCV patients vs 10 healthy controls; P < 0.001) but not in patients with primary biliary cirrhosis. Successful antiviral therapy of chronic hepatitis C rescued the cytotoxicity of DCs. Myeloid DCs of HCV patients and healthy controls had a similar phenotype and endocytotic activity, however, the frequency of mDCs in the peripheral blood was lower (P = 0.004) and the allostimulatory function was weaker (P < 0.001) in chronic hepatitis C. Thus, in contrast to HIV and measles virus studies on monocyte-derived DCs, freshly isolated myeloid DCs of patients with hepatitis C do not show an increased but a completely abolished cytotoxic activity. The impaired DC cytotoxicity could represent a novel mechanism for the increased prevalence of autoimmunity in HCV infection. 相似文献
928.
Paczkowska E Larysz B Rzeuski R Karbicka A Jałowiński R Kornacewicz-Jach Z Ratajczak MZ Machaliński B 《European journal of haematology》2005,75(6):461-467
The hematopoietic and non-hematopoietic stem/progenitor cells harvested directly from the bone marrow (BM) or G-CSF mobilized peripheral blood were demonstrated to play an important role in regeneration of damaged organs (1, 2). Here, we asked if the stroke- or acute heart infarct-related stress triggers mobilization of stem/progenitor-enriched CD34(+)cells from the BM into the peripheral blood, which subsequently could contribute to regeneration of damaged tissues. To address this question the peripheral blood samples were harvested from patients with ischemic stroke during the first 24 h of manifestation of symptoms and on the second and sixth day afterwards or during the first 24 h of acute cardiac pain as well as on the second and sixth day of infarct. We measured in these patients (i) percentage of circulating hematopoietic stem/progenitor-enriched CD34(+) cells in peripheral blood by employing fluorescence activated cell sorter (FACS) and (ii) number of hematopoietic progenitor cells for the granulocyte-monocytic colony-forming unit (CFU-GM) and erythoid burst-forming unit (BFU-E) lineages circulating in peripheral blood. We concluded that stress related to ischemic stroke or acute myocardial infarction triggers the mobilization of hematopoietic stem/progenitor-enriched CD34(+) cells from the BM into peripheral blood. These circulating stem/progenitor-enriched CD34(+) cells may contribute to the regeneration of ischemic tissues, however, this possibility requires further studies. 相似文献
929.
Bolognesi A Polito L Tazzari PL Lemoli RM Lubelli C Fogli M Boon L de Boer M Stirpe F 《British journal of haematology》2000,110(2):351-361
Immunotoxins specific for the CD80 and CD86 antigens were prepared by linking three type 1 ribosome-inactivating proteins (RIPs), namely bouganin, gelonin and saporin-S6, to the monoclonal antibodies M24 (anti-CD80) and 1G10 (anti-CD86). These immunotoxins showed a specific cytotoxicity for the CD80/CD86-expressing cell lines Raji and L428. The immunotoxins inhibited protein synthesis by target cells with IC50s (concentration causing 50% inhibition) ranging from 0.25 to 192 pmol/l as RIPs. The anti-CD80 immunotoxins appeared 1-2 log more toxic for target cells than the anti-CD86 ones. Immunotoxins containing saporin and bouganin induced apoptosis of target cells. The toxicity for bone marrow haemopoietic progenitors of these conjugates was also evaluated. Bouganin and related immunotoxins at concentrations up to 100 nmol/l did not significantly affect the recovery of committed progenitors or of more primitive cells. The saporin-containing immunotoxins at concentrations >/= 1 nmol/l showed some toxicity on colony-forming unit cells (CFU-C). The expression of the CD80 and CD86 molecules is prevalently restricted to antigen-presenting cells and is also strong on Hodgkin and Reed-Sternberg cells in Hodgkin's disease. Present results suggest that immunotoxins targeting type 1 ribosome-inactivating proteins to these antigens could be considered and further studied for the therapy of Hodgkin's disease or other CD80/CD86-expressing tumours. 相似文献
930.
L. Brancato S. Itescu M. L. Skovron G. Solomon R. Winchester 《Rheumatology international》1989,9(3-5):137-141
Summary Arthrocutaneous disorders including Reiter's syndrome, psoriasiform rashes, and other forms of chronic arthritis and enthesopathy, such as psoriatic arthritis, occur with an increased prevalence in the setting of HIV infection. Herein we describe the spectrum and prevalence of musculoskeletal and allied skin disorders as they occur in the setting of HIV infection. The role of genetic susceptibility in the development of these disorders is addressed. Based on the frequency of infectious agents capable of triggering reactive arthritis and the presence of HLA-B27 in 71% of these individuals, it is suggested that the disorder strongly resembles Reiter's syndrome as it occurs in the not HIV-infected group. Preliminary evidence indicates an enhanced penetrance for susceptibility among HLA-B27 individuals. In contrast, among HIV-infected patients with psoriasiform lesions there was no statistically significant association (P<0.05) between the presence of psoriasiform rash and the HLA alleles Cw6, B7, B17, Bw16, or Bw57 when compared with HIV-infected controls. These findings suggest that among HIV-infected individuals the development of Reiter's syndrome involves an immune recognition event primarily dependent upon HLA-B27 molecules in which an unknown antigen in the context of HLA-B27 is presented to CD8 lineage suppressor/cytotoxic cells. In contrast, the pathogenesis of psoriasiform lesions in HIV patients, despite their similarity to certain lesions in Reiter's syndrome, proceeds by distinct pathways that do not involve events influenced by specific polymorphic class I molecules. 相似文献