We tested the hypothesis that water Ca is involved in control of branchial Na permeability in low pH tolerant convict cichlids and black neon tetras. We measured Na efflux in water with different Ca concentrations during exposure to low pH, silver, and copper, at levels which are known to stimulate Na efflux. For convict cichlids at pH 7.
View Article and Find Full Text PDFObjective: The importance of cold-shock Y-box binding protein 1 (YB-1) for cell homeostasis is well-documented based on prior observations of its association with certain cancer entities. This study was undertaken to explore the role of YB-1 in T cell homeostasis and survival and the potential contribution of YB-1 to the pathogenesis of systemic lupus erythematosus (SLE).
Methods: In the peripheral blood from 25 SLE patients and 25 healthy donors, the expression of YB-1 and frequency of T cell apoptosis was analyzed by quantitative polymerase chain reaction (qPCR) and fluorescence-activated cell sorting of CD4+ T cells ex vivo and also analyzed in T cells in vitro after 6 days of stimulation with anti-CD3-coupled or anti-CD3/anti-CD28-coupled microspheres.
J Eur Acad Dermatol Venereol
December 2016
In atopic dermatitis (AD), the skin barrier is disturbed, and the expression of calcium-dependent S100 proteins and the calcium gradient is also altered in the epidermis. The calmodulin-like skin protein (CLSP), which is expressed in the differentiated epidermis, is believed to modulate the function of calcium-dependent proteins involved in barrier formation and is significantly increased in the epidermis of psoriatic patients. We, therefore, investigated the CLSP level in skin biopsies taken from patients with acute exacerbated and non-exacerbated AD as well as from healthy control subjects.
View Article and Find Full Text PDFBackground: Skin blistering diseases due to autoantibodies are typically treated with high dose systemic corticosteroids and other conventional immunosuppressants. However, in severe cases, this treatment may not be sufficient to achieve disease control or contraindicated because of comorbidity.
Methods: We describe 15 patients (pts.
Dystrophic epidermolysis bullosa (DEB) is a rare hereditary skin disorder caused by mutations in COL7A1, encoding collagen type VII.1 Clinical manifestations of COL7A1 mutations range from generalized skin blistering to mild localized blistering or nail dystrophy.2 The investigation of the molecular basis of DEB has revealed more than 540 different mutations that cannot entirely explain phenotypic variations (HGMD Professional 2010.
View Article and Find Full Text PDFCTLA-4 (CD152) is a regulatory molecule in the immune system fundamentally important for the inhibition of T cell activity that is mediated by an unknown mechanism. Here we demonstrate similarities of CTLA-4 and Itch deficient mice and that CTLA-4 deficient T cells show a massive reduction in the overall ubiquitination of proteins. CTLA-4-mediated signal transduction leads to increased de-phosphorylation and therefore activation of the ubiquitin ligase Itch and enhanced ubiquitination of the Itch target molecule JunB.
View Article and Find Full Text PDFDigital ulcers in progressive systemic sclerosis (PSS) are often refractory to therapy. A frequently chronic aggressive course can lead to the loss of acral limbs involved. A 73-year-old woman developed a dramatic worsening of her ulcerations despite maximum conventional therapy.
View Article and Find Full Text PDFEngagement of the TCR can induce different functional outcomes such as activation, proliferation, survival, or apoptosis. How the TCR-mediated signaling cascades generating these distinct cellular responses are organized on the molecular level is so far not completely understood. To obtain insight into this question, we analyzed TCR/CD8-mediated signaling events in mature OT-I TCR transgenic T cells under conditions of stimulation that lead to either proliferation or apoptosis.
View Article and Find Full Text PDFUVA1-irradiation was introduced as an innovative and effective phototherapy of atopic dermatitis (AD) and other skin diseases. In AD, a defect of a central apoptosis inducing effector system involved in immunoregulation and immune defense, i.e.
View Article and Find Full Text PDFPerforin-containing lytic granules are secretory lysosomes of cytotoxic lymphocytes. They act as a negative regulator of activated T cells, control immunoglobulin production, contribute to the regulation of the TH1/TH2 balance, and occupy a central role in anti-viral defense mechanisms. This review focuses on recent evidence for a fundamental defect in the lymphocytic perforin system of atopic patients, namely perforin reduction and the hyperreleasability of perforin granules.
View Article and Find Full Text PDFCD8(hi+) cytotoxic T lymphocytes (CTL) are major players in immune defense. In addition, they contribute to the maintenance of immune homeostasis. We now describe a hitherto unavailable, but simple assay to determine ex vivo lytic granule-based cytotoxic functions of human CD8(hi+) CTL subgroups in a clinical setting, under target cell free conditions.
View Article and Find Full Text PDFImiquimod (IMQ), an activator of Toll-like receptor-7 (TLR-7), induces by several routes a profound anti-viral and anti-tumor effect in vivo. Physiologically, the immune system is using perforin-containing granules of cytotoxic T lymphocytes (CTL) towards the same biological purpose. This functional synergism prompted our current experiments addressing the question whether IMQ may influence perforin-release and/or induce perforin in CTLs in vitro.
View Article and Find Full Text PDFThe system of perforin-containing lytic granules of cytotoxic lymphocytes plays an important role in the immune defense machinery. Investigating the capacity and efficacy of this system in and ex vivo is helpful to understand immune responses and their modulation by therapeutic interventions. With regard to its pathophysiological function, we recently demonstrated a substantial increase of perforin-positive CD8+ T cells in the peripheral blood of patients with acute exacerbated psoriasis and severe generalized drug reactions, and, in marked contrast, a highly significant perforin-depletion and a perforin-hyperreleasability in atopic dermatitis (AD).
View Article and Find Full Text PDFEndogenous antioxidants are decreased in skin and blood during UV exposure. Combined supplementation of beta-carotene, alpha-tocopherol and ascorbic acid in addition to topical sunscreens may help to lower the risk of sunburning. Acute UV erythema with sunburn reaction are the most important factors in conjunction with the cumulative life-long UV dose for inducing skin damage resulting in photoageing and precancerous and cancerous lesions.
View Article and Find Full Text PDFWhile the recycling pathway of endocytosis has been shown to participate in many cellular functions, little is known regarding the transport carriers that mediate this pathway. In this study, we overexpressed a point mutant of ADP-ribosylation factor 6 (ARF6), that perturbs its GTPase cycle, to accumulate endosome-derived coated vesicles. Characterization by their purification revealed that, upon cell homogenization, these vesicles were mostly aggregated with larger noncoated membranes, and could be released with high-salt treatment.
View Article and Find Full Text PDFSkin Pharmacol Appl Skin Physiol
December 2001
The 70-kD plasma membrane pore-forming protein perforin is a key component of lymphocyte cytotoxicity mediated by lytic granules. It represents a major player in the regulation of various immune reactions like immunoglobulin synthesis, T-cell activation and homeostasis, and in the elimination of virus-infected and tumor cells. Dysregulation of the perforin-granule system, i.
View Article and Find Full Text PDFSkin Pharmacol Appl Skin Physiol
September 2001
In psoriasis an etiopathogenetic vicious circle has been hypothesized in which disease manifestation is triggered by skin-specific autoantigen structures. Autoreactive T cells are supposed to mediate inflammation and hyperproliferation in the epidermopapillary compartment, positively feeding back the expression and accessibility of decisive antigen structures. Recently an epitope within cytokeratin 17 (K17) has been described as such a putative psoriasis autoantigen, which is moreover known to be up-regulated under the influence of proinflammatory interferon-gamma (IFN-gamma), which is abundantly detected in psoriatic plaques.
View Article and Find Full Text PDFBackground: As a plasma membrane pore-forming protein, perforin is essential for T-cell cytotoxicity mediated by lytic granules. Recent studies on the immune system of perforin knockout mice demonstrated striking similarities to the immunopathology of atopic diseases.
Objective: We sought to investigate the perforin system of atopic patients.
Cofilin, an actin-depolymerizing protein, is essential for the functional dynamics of the actin cytoskeleton and for cell viability. In unstimulated human peripheral blood T lymphocytes cofilin is phosphorylated and localized in the cytoplasm. Following co-stimulation through accessory receptors (e.
View Article and Find Full Text PDF