Search results for "Clear Cell"
showing 10 items of 339 documents
T lymphocyte control of autoreactivity: analysis with human T cell clones and limiting dilution culture
1986
To investigate cellular mechanisms controlling activated autoreactive T lymphocytes, a limiting dilution system was established employing cloned autoreactive major his-tocompatibility complex class II specific lymphocytes (a2/7) as stimulator cells for autologous peripheral blood mononuclear cells. At low responder/stimulator ratios, cytotoxic effector cells were generated capable of lysing clone a2/7. Importantly, within the population of cells mediating autocytotoxic effector function, differential specificities were found to exist. The generation of such autocytotoxic T lymphocytes appears to be inhibited by an additional population of cells circulating at lower frequency suggesting that…
Flupirtine protects both neuronal cells and lymphocytes against induced apoptosis in vitro: Implications for treatment of AIDS patients
1999
In the present study we demonstrate that flupirtine, an already clinically used, centrally acting, non-opiate analgesic agent, protects rat cortical neurons against HIV-gp120 induced apoptotic cell death. The drug was active at concentrations between 1 and 10 microg/ml. Furthermore we show inhibition of in vitro induced apoptosis in human blood mononuclear cells, using flupirtine. Induced apoptosis in peripheral blood mononuclear cells from healthy individuals and HIV-1 infected patients was reduced to approximately 50% after in vitro preincubation with flupirtine at concentrations between 0.1 and 10 microg/ml. The anti-apoptotic effect of flupirtine was restricted to CD3+ lymphocytes and i…
The 2-5A System and HIV Infection
1994
The human immunodeficiency virus type 1 (HIV-1) is the etiologic agent of acquired immunodeficiency syndrome (AIDS). The progression of this retro viral disease is associated with various clinical manifestations, including the acquisition of an immunodeficient state, the frequent presence of neurological disorders, and some malignancies (reviewed in Barre-Sinoussi et al. 1983; Wong-Staal and Gallo 1985; Fauci 1988). Immunologic dysfunctions caused by HIV-1 infection include disorders in the production of cytokines (Murray et al. 1984; Abb et al. 1986). For example, a significant decrease in the production of interferon-α (IFN-α) by cultured peripheral blood mononuclear cells (PBMC) from pat…
Enrichment of Outgrowth Endothelial Cells in High and Low Colony-Forming Cultures from Peripheral Blood Progenitors
2009
An effective isolation protocol for outgrowth endothelial cells (OEC) resulting in higher cell numbers and a reduced expansion time would facilitate the therapeutical application. In this study a standard protocol based on the isolation of mononuclear cells from adult peripheral blood was modified by adding a passaging step 7 days after the isolation. OEC colonies gained by both protocols were evaluated after 28 days and resulted in different frequencies of OEC colonies depending on the donor and culture protocol. Accordingly, we defined two groups, namely, high colony-forming cultures (HCC) and low colony-forming cultures (LCC) for further analysis. LCC revealed no increase in OEC colonies…
Abacavir and didanosine induce the interaction between human leukocytes and endothelial cells through Mac-1 upregulation
2010
Objective: Abacavir and didanosine are nucleoside reverse transcriptase inhibitors (NRTI) widely used in therapy for HIV-infection but which have been linked to cardiovascular complications. The objective of this study was to analyze the effects of clinically relevant doses of abacavir and didanosine on human leukocyte―endothelium interactions and to compare them with those of other NRTIs. Design and methods: The interactions between human leukocytes ― specifically peripheral blood polymorphonuclear (PMN) or mononuclear (PBMC) cells ― and human umbilical vein endothelial cells were evaluated in a flow chamber system that reproduces conditions in vivo. The expression of adhesion molecules wa…
Characterization of a novel population of low-density granulocytes associated with disease severity in HIV-1 infection
2012
The mechanisms resulting in progressive immune dysfunction during the chronic phase of HIV infection are not fully understood. We have previously shown that arginase, an enzyme with potent immunosuppressive properties, is increased in HIV seropositive (HIV+) patients with low CD4(+) T cell counts. Here we show that the cells expressing arginase in peripheral blood mononuclear cells of HIV+ patients are low-density granulocytes (LDGs) and that whereas these cells have a similar morphology to normal-density granulocyte, they are phenotypically different. Importantly, our results reveal that increased frequencies of LDGs correlate with disease severity in HIV+ patients.
The histology of ovarian cancer: worldwide distribution and implications for international survival comparisons (CONCORD-2).
2016
OBJECTIVE: Ovarian cancers comprise several histologically distinct tumour groups with widely different prognosis. We aimed to describe the worldwide distribution of ovarian cancer histology and to understand what role this may play in international variation in survival. METHODS: The CONCORD programme is the largest population-based study of global trends in cancer survival. Data on 681,759 women diagnosed during 1995-2009 with cancer of the ovary, fallopian tube, peritoneum and retroperitonum in 51 countries were included. We categorised ovarian tumours into six histological groups, and explored the worldwide distribution of histology. RESULTS: During 2005-2009, type II epithelial tumours…
Anti-HIV-1 activity of inorganic polyphosphates.
1997
Human blood plasma, serum, peripheral blood mononuclear cells, and erythrocytes contain significant amounts of inorganic polyphosphates (ranging from 53 to 116 microM, in terms of phosphate residues). Here we demonstrate that at higher concentrations linear polyphosphates display cytoprotective and antiviral activity. Sodium tetrapolyphosphate and the longer polymers, with average chain lengths of 15, 34, and 91 phosphate residues, significantly inhibited human immunodeficiency virus type 1 (HIV-1) infection of cells in vitro at concentrations > or = 33.3 microg/ml (> or = 283-324 microM phosphate residues), whereas sodium tripolyphosphate was ineffective. In the tested concentration range,…
Analysis of DNA single-strand breaks in human venous blood: a technique which does not require isolation of white blood cells.
1997
For DNA strand break analysis in human white blood cells, usually metrizoate-Ficoll centrifugation is used to isolate mononuclear cells. This procedure is time-consuming and requires at least 20 ml of blood per sample. Therefore, we developed a technique which does not require isolation of white blood cells prior to DNA strand break analysis by alkaline elution (direct method). The sensitivity of this new technique was compared to that of the standard method, which includes isolation of mononuclear blood cells. A statistically significant increase in sensitivity was observed using the direct method. After in vitro gamma-irradiation of venous blood, an increase in the elusion rate of 7.7 × 1…
Correlation between HHV-6 reactivation and multiple sclerosis disease activity.
2002
This study examined the association between HHV-6 infection and multiple sclerosis (MS) and the relationship between HHV-6 reactivation and disease activity. The frequency of HHV-6 genomic sequences in peripheral blood mononuclear cells (PBMCs), the incidence of plasma viremia (nPCR), the transcription of viral mRNA in PBMCs (RT-PCR), the presence of antiviral IgM and IgG class antibodies in the plasma (IFA) of 16 relapsing/remitting and secondary progressive MS patients were studied in comparison with clinical manifestations of the disease, magnetic resonance imaging (MRI) of brain, and serum interleukin (IL)-12 concentrations (ELISA). The prevalence of HHV-6 infection was significantly hi…