Search results for "Apoptosi"
showing 10 items of 1846 documents
Lymphoma cell apoptosis in the liver induced by distant murine cytomegalovirus infection.
2006
ABSTRACTCytomegalovirus (CMV) poses a threat to the therapy of hematopoietic malignancies by hematopoietic stem cell transplantation, but efficient reconstitution of antiviral immunity prevents CMV organ disease. Tumor relapse originating from a minimal residual leukemia poses another threat. Although a combination of risk factors was supposed to enhance the incidence and severity of transplantation-associated disease, a murine model of a liver-adapted B-cell lymphoma has previously shown a survival benefit and tumor growth inhibition by nonlethal subcutaneous infection with murine CMV. Here we have investigated the underlying antitumoral mechanism. Virus replication proved to be required, …
Relationship between apoptosis and survival molecules in human cumulus cells as markers of oocyte competence
2017
SummaryTo select from a single patient the best oocytes able to reach the blastocyst stage, we searched for valuable markers for oocytes competence. We evaluated the DNA fragmentation index (DFI) and the level of some survival molecules, such as AKT, pAKT and pERK1/2, in individual cumulus cell–oocyte complexes (COC). The study included normo-responder women. The average age of the patients was 34.3. DFI in cumulus cells was evaluated using the terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labelling (TUNEL) assayin situ. AKT, pAKT and pERK1/2 were measured by immunological assay and densitometric analysis of fluorescent signals using NIS-Elements BR 3.10 image software. Statisti…
Serotherapy with thymoglobulin and alemtuzumab differentially influences frequency and function of natural killer cells after allogeneic stem cell tr…
2007
Although thymoglobulin and alemtuzumab are frequently used in hematopoietic stem cell transplantation (HSCT), little is known of their effects on NK cells, which mediate important functions in post-transplantation immunology. In the present study, we determined NK cell death in vitro using propidium iodide and Annexin V. The NK cell activity in 34 patients at day +30 after allogeneic HSCT was assessed using the CD107a assay. Alemtuzumab and thymoglobulin were similarly very potent in inducing NK cell death in vitro. Even in low concentrations (1 microg/ml) the antibodies induced apoptosis and necrosis in a relevant percentage of NK cells (30%). However, the number of tumor reactive (CD107a+…
Inhibition of tumor cell proliferation in human uterine leiomyomas by vitamin D via Wnt/β-catenin pathway.
2018
To assess the effect of vitamin D (VitD) on human uterine leiomyomas through Wnt/β-catenin pathway inhibition, apoptosis induction, and cell growth arrest.A prospective study comparing leiomyoma vs. myometrium tissues. Paired design study comparing human uterine leiomyoma primary (HULP) cells treated with or without VitD.University hospital.Human uterine leiomyoma and myometrium were collected from women (aged 35-52 years) without hormonal treatment.Samples were collected from women undergoing surgery due to symptomatic uterine leiomyoma pathology.Uterine leiomyoma and myometrium tissues were analyzed by western blot (WB) to determine proliferation, Wnt/β-catenin, and apoptosis pathways. HU…
Low bcl-2 expression and increased spontaneous apoptosis in T-lymphocytes from newly-diagnosed IDDM patients.
1995
The bcl-2 gene product has been shown to regulate apoptotic cell death, and its dysregulation has been shown to induce several abnormalities in the immune system. No data exist regarding bcl-2 expression in autoimmune diseases, such as human insulin-dependent diabetes mellitus (IDDM). We investigated bcl-2 protein expression by testing T lymphocytes from 15 newly-diagnosed (3 weeks) IDDM patients in comparison to 10 age-matched control subjects. The expression of bcl-2 on CD3+ lymphocyte subsets was investigated after membrane permeabilization by two- or three-colour immunofluorescence. When the percentage and mean fluorescence intensity (MFI) of bcl-2+/CD3+ cells from normal individuals an…
The transcription factor IFN regulatory factor–4 controls experimental colitis in mice via T cell–derived IL-6
2008
The proinflammatory cytokine IL-6 seems to have an important role in the intestinal inflammation that characterizes inflammatory bowel diseases (IBDs) such as Crohn disease and ulcerative colitis. However, little is known about the molecular mechanisms regulating IL-6 production in IBD. Here, we assessed the role of the transcriptional regulator IFN regulatory factor-4 (IRF4) in this process. Patients with either Crohn disease or ulcerative colitis exhibited increased IRF4 expression in lamina propria CD3+ T cells as compared with control patients. Consistent with IRF4 having a regulatory function in T cells, in a mouse model of IBD whereby colitis is induced in RAG-deficient mice by transp…
MMP-7 promoter polymorphisms do not influence CD4+ recovery and changes in plasma viral load during antiretroviral therapy for HIV-1 infection.
2005
Summary Matrix metalloproteinase-7 (MMP-7) generates soluble Fas Ligand (FasL), which is involved in the apoptotic loss of CD4+ T cells during HIV infection. We evaluated whether two polymorphisms in MMP-7 promoter could influence CD4+ recover in response to antiretroviral therapy, and found that these polymorphisms are ineffective.
CD4+ CCR5+ and CD4+ CCR3+ lymphocyte subset and monocyte apoptosis in patients with acute visceral leishmaniasis
2004
The potential involvement of apoptosis in the pathogenesis of visceral leishmaniasis (VL) was examined by studying spontaneous and Leishmania antigen (LAg)-induced apoptosis using cryopreserved peripheral blood mononuclear cells (PBMC) of Sicilian patients with VL. Results indicate that monocytes and T lymphocytes from acute VL patients show a significantly higher level of apoptosis compared with that observed in healed subjects. The percentage of apoptotic cells was higher in monocytes than in T lymphocytes. T cells involved in programmed cell death (PCD) were mainly of the CD4(+) phenotype. In particular, the T helper 1-type (Th1) subset, as evaluated by chemokine receptor-5 (CCR5) expres…
CD28-dependent Rac1 activation is the molecular target of azathioprine in primary human CD4+ T lymphocytes
2003
Azathioprine and its metabolite 6-mercaptopurine (6-MP) are immunosuppressive drugs that are used in organ transplantation and autoimmune and chronic inflammatory diseases such as Crohn disease. However, their molecular mechanism of action is unknown. In the present study, we have identified a unique and unexpected role for azathioprine and its metabolites in the control of T cell apoptosis by modulation of Rac1 activation upon CD28 costimulation. We found that azathioprine and its metabolites induced apoptosis of T cells from patients with Crohn disease and control patients. Apoptosis induction required costimulation with CD28 and was mediated by specific block- ade of Rac1 activation thro…
Azathioprine suppresses ezrin-radixin-moesin-dependent T cell-APC conjugation through inhibition of Vav guanosine exchange activity on rac proteins
2006
Abstract We have shown recently that the azathioprine metabolite 6-Thio-GTP causes immunosuppression by blockade of GTPase activation in T lymphocytes. In the present study, we describe a new molecular mechanism by which 6-Thio-GTP blocks GTPase activation. Although 6-Thio-GTP could bind to various small GTPases, it specifically blocked activation of Rac1 and Rac2 but not of closely related Rho family members such as Cdc42 and RhoA in primary T cells upon stimulation with αCD28 or fibronectin. Binding of 6-Thio-GTP to Rac1 did not suppress Rac effector coupling directly but blocked Vav1 exchange activity upon 6-Thio-GTP hydrolysis, suggesting that 6-Thio-GTP loading leads to accumulation of…