Search results for "LPE"
showing 10 items of 493 documents
The Transcription Factor T-bet Regulates Mucosal T Cell Activation in Experimental Colitis and Crohn's Disease
2002
The balance between pro and antiinflammatory cytokines secreted by T cells regulates both the initiation and perpetuation of inflammatory bowel diseases (IBD). In particular, the balance between interferon (IFN)-gamma/interleukin (IL)-4 and transforming growth factor (TGF)-beta activity controls chronic intestinal inflammation. However, the molecular pathways that evoke these responses are not well understood. Here, we describe a critical role for the transcription factor T-bet in controlling the mucosal cytokine balance and clinical disease. We studied the expression and function of T-bet in patients with IBD and in mucosal T cells in various T helper (Th)1- and Th2-mediated animal models …
Immunological pattern in patients with 21-hydroxylase deficiency.
1994
The aim of this work was to perform an immunological study in six patients with 21 hydroxylase deficiency in mild form (M210HD) and in 2 patients with 21-hydroxylase deficiency in classical form (C210HD) and in their parents, in whom a previous HLA,C4,Bf typing demonstrated high prevalence of DR5 and phenotypic absence of fraction C4B of complement (C4BQO). This study contains the evaluation of C3, IgA, IgG, IgM levels, anticardiolipin antibodies (IgG and IgM) and circulating immunocomplexes. A study of lymphocyte subsets was also performed. Among M210HD 1 patient showed presence of anticardiolipin antibodies both IgM and IgG; this patient had shown antinuclear antibodies in a previous stud…
Induction of Interleukin 10–Producing, Nonproliferating Cd4+ T Cells with Regulatory Properties by Repetitive Stimulation with Allogeneic Immature Hu…
2000
The functional properties of dendritic cells (DCs) are strictly dependent on their maturational state. To analyze the influence of the maturational state of DCs on priming and differentiation of T cells, immature CD83− and mature CD83+ human DCs were used for stimulation of naive, allogeneic CD4+ T cells. Repetitive stimulation with mature DCs resulted in a strong expansion of alloreactive T cells and the exclusive development of T helper type 1 (Th1) cells. In contrast, after repetitive stimulation with immature DCs the alloreactive T cells showed an irreversibly inhibited proliferation that could not be restored by restimulation with mature DCs or peripheral blood mononuclear cells, or by…
Tcgfiii/p40 is produced by naive murine cd4+ t cells but is not a general t cell growth factor*
1989
Several antigen-specific T cell lines were found to secrete a lymphokine upon activation by antigen or lectin that was provisionally termed T cell growth factor III (TCGF III) because it induced the proliferation of a CD4+ T cell clone independently from IL2 and IL4. Amino acid sequence analysis (and the functional properties of TCGF III) revealed that TCGF III was identical with a recently identified lymphokine termed P40. TCGF III/P40 was not only produced by long-term cultured T cell lines but also upon stimulation of freshly isolated Mlsa-reactive T cells. In addition, naive CD4+ T cells secreted TCGF III/P40 upon activation by lectin or allo-major histocompatibility complex structures.…
Autocrine transforming growth factor- from chronic lymphocytic leukemia-β cells interferes with proliferative T cell signals
1999
Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of noncycling B cells in lymphatic and extralymphatic tissues. In the present study we investigated the possible contribution of TGF-beta, as secreted by CLL-B cells, on this low proliferative state. CLL-B cells were shown to express TGF-beta RNA and to release bioactive TGF-beta into culture supernatants. Antibody neutralization of endogenously secreted TGF-beta increased the proliferation of CLL-B cells as cultured in the presence of IL-2 or IL-4 or in direct contact with activated CD4+ T cells. In these culture systems, addition of exogenous TGF-beta downregulated basal and cytokineinduced proliferation of CLL-B cell…
Quantitative representation of all T cells committed to develop into cytotoxic effector cells and/or interleukin 2 activity-producing helper cells wi…
1984
A limiting dilution culture system based on stimulation with concanavalin A (Con A) has been used to study the quantitative distribution of helper and of cytotoxic precursor cells in Lyt-2-defined subpopulations of murine T cells. Virtually all of the selected Lyt-2+ and Lyt-2-T cells grow and expand to large clonal colonies within an 8-9-day culture period. Our data show that upon stimulation with Con A, 90% of the Lyt-2-T cells were capable to produce interleukin 2 (IL 2) activity. In addition, IL 2 activity is produced by 8-10% of Lyt-2+ T cells. However, at the clonal level, the average of the IL2 activity produced by Lyt-2+ T cells is about 8-fold less as compared to Lyt-2-T cells. Pre…
T helper cell populations: As flexible as the skin?
2011
T helper cells can be defined by the cytokines they produce and are divided into Th1, Th2, Th17, T(FH) or regulatory T cells. Th17 cells have been shown to produce, in addition to IL-17, IL-22. In the current issue of the European Journal of Immunology, an article by Larsen et al. (Eur. J. Immunol. 2011. 41: 2596-2605) provides evidence that human T helper cells, like murine cells, can also express IL-22 in the absence of the other T helper cell signature cytokines. Moreover, they show that these IL-22-producing cells, namely Th22 cells, can be found in the skin of psoriasis patients, where they might contribute to the pathogenesis of this inflammatory skin disease. Finally, they show that,…
Tree visitation and seed dispersal of wild cherries by terrestrial mammals along a human land-use gradient
2010
Abstract The role of terrestrial mammals as seed dispersers of fleshy-fruited plants has only rarely been investigated in temperate regions although recent studies underline the importance of these animals for long-distance seed dispersal. Here we examine the potential role of mammals as seed dispersers of wild cherry (Prunus avium L.) along a gradient of human land-use intensity. We placed camera traps at 21 wild cherry trees to identify the mammal species that visited the trees. We conducted feeding trials to test if the recorded species were legitimate seed dispersers or seed predators and to assess gut passage times. We tested the influence of human land-use intensity by quantifying hab…
Allogeneic effector/memory Th-1 cells impair FoxP3+ regulatory T lymphocytes and synergize with chaperone-rich cell lysate vaccine to treat leukemia
2011
AbstractTherapeutic strategies combining the induction of effective antitumor immunity with the inhibition of the mechanisms of tumor-induced immunosuppression represent a key objective in cancer immunotherapy. Herein we demonstrate that effector/memory CD4+ T helper-1 (Th-1) lymphocytes, in addition to polarizing type-1 antitumor immune responses, impair tumor-induced CD4+CD25+FoxP3+ regulatory T lymphocyte (Treg) immunosuppressive function in vitro and in vivo. Th-1 cells also inhibit the generation of FoxP3+ Tregs from naive CD4+CD25−FoxP3− T cells by an interferon-γ–dependent mechanism. In addition, in an aggressive mouse leukemia model (12B1), Th-1 lymphocytes act synergistically with …
In Vivo Imaging of Partially Reversible Th17 Cell-Induced Neuronal Dysfunction in the Course of Encephalomyelitis
2010
SummaryNeuronal damage in autoimmune neuroinflammation is the correlate for long-term disability in multiple sclerosis (MS) patients. Here, we investigated the role of immune cells in neuronal damage processes in animal models of MS by monitoring experimental autoimmune encephalomyelitis (EAE) by using two-photon microscopy of living anaesthetized mice. In the brainstem, we detected sustained interaction between immune and neuronal cells, particularly during disease peak. Direct interaction of myelin oligodendrocyte glycoprotein (MOG)-specific Th17 and neuronal cells in demyelinating lesions was associated with extensive axonal damage. By combining confocal, electron, and intravital microsc…