Search results for "Epidermis"
showing 10 items of 151 documents
Use of cultured human epithelium for coverage: a defect of radial forearm free flap donor site
2010
The radial forearm free flap has been popular in many areas of reconstructive surgery. Despite the many attributes of this flap in maxillofacial reconstruction, one of the disadvantages has been the morbidity of the donor site. Allogeneic cultured epidermis has been successfully applied on large second degree burns and on chronic leg ulcers. Autologous human keratinocytes and fibroblast equivalents can be cultured in-vitro from a small skin sample in order to produce a sufficient amount of epithelial autografts to cover the large defects of third-degree burn wounds. Interestingly, transplanted cultured epidermis retains characteristics of the original donor site. We report a case of a patie…
Avarol inhibits TNF-a generation and NF-kB activation in human cells and in animal models
2007
Avarol is a marine sesquiterpenoid hydroquinone with interesting pharmacological properties including anti-inflammatory and antipsoriatic effects. In the present study we evaluated the pharmacological effect of avarol on some inflammatory parameters related to the pathogenesis of psoriasis. Avarol inhibited tumor necrosis factor-alpha (TNF-alpha) generation in stimulated human monocytes (IC(50) 1 microM) and TNF-alpha-induced activation of nuclear factor-kappaB (NF-kappaB)-DNA binding in keratinocytes. In the mouse air pouch model, administration of avarol produced a dose-dependent reduction of TNF-alpha generation (ED(50) 9.2 nmol/pouch) as well as of interleukin (IL)-1beta, prostaglandin …
Induction of inflammatory cytokines in murine keratinocytes upon in vivo stimulation with contact sensitizers and tolerizing analogues
1992
In order to elucidate the role of keratinocytes (KCs) in the induction of contact sensitivity, we applied various contact sensitizers [2,4-dinitrofluorobenzene (DNFB), urushiol, 3-n-pentadecylcatechol (PDC), 4-ethoxymethylene-2-phenyloxazol-5-one (oxazolone)] and tolerizing compounds [2,4-dinitrothiocyanobenzene (DNTB), 5-methyl-3-n-pentadecyl-catechol (5-Me-PDC)] onto the earskin of non-sensitized Balb/c mice. In addition, we applied croton oil as a non-sensitizing, but stimulatory agent. Cytokine production was demonstrated by Northern blot hybridization of the total cellular RNA extracted from epidermal cells depleted by Langerhans cells and Thy 1+ dendritic cells using radiolabeled DNA …
Resistance of keratinocytes to TGFbeta-mediated growth restriction and apoptosis induction accelerates re-epithelialization in skin wounds.
2002
The pleiotropic growth factor TGFβ plays an important role in regulating responses to skin injury. TGFβ targets many different cell types and is involved in all aspects of wound healing entailing inflammation,re-epithelialization, matrix formation and remodeling. To elucidate the role of TGFβ signal transduction in keratinocytes during cutaneous wound healing, we have used transgenic mice expressing a dominant negative type II TGFβ receptor exclusively in keratinocytes. We could demonstrate that this loss of TGFβ signaling in keratinocytes led to an accelerated re-epithelialization of full thickness excisional wounds accompanied by an increased proliferation in keratinocytes at the wound ed…
Biomimetic Alginate/Gelatin Cross-Linked Hydrogels Supplemented with Polyphosphate for Wound Healing Applications
2020
In the present study, the fabrication of a biomimetic wound dressing that mimics the extracellular matrix, consisting of a hydrogel matrix composed of non-oxidized and periodate-oxidized marine alginate, was prepared to which gelatin was bound via Schiff base formation. Into this alginate/oxidized-alginate-gelatin hydrogel, polyP was stably but reversibly integrated by ionic cross-linking with Zn2+ ions. Thereby, a soft hybrid material is obtained, consisting of a more rigid alginate scaffold and porous structures formed by the oxidized-alginate-gelatin hydrogel with ionically cross-linked polyP. Two forms of the Zn-polyP-containing matrices were obtained based on the property of polyP to f…
Multicolor fate mapping of Langerhans cell homeostasis
2013
The adult epidermal Langerhans cell network is formed by adjacent proliferative units composed of dividing cells and their terminally differentiated daughter cells.
Maturation of epidermal Langerhans cells: increased expression of beta- and gamma-actin isoforms as a basis of specialized cell functions.
1999
Epidermal Langerhans cells (LC) represent immature dendritic cells. During in vitro culture in the presence of keratinocytes they mature into potent immunostimulatory cells for naive T cells. This process is thought to simulate in vivo maturation of LC following activation by antigen contact. Maturation of LC is accompanied by morphological alterations. Applying a differential screening procedure we isolated differentially expressed cDNAs involved in the maturation events including cDNAs of the cytoskeletal actin isoforms beta- and gamma-actin. Stronger signals with hybridization probes derived from cultured LC compared with probes derived from freshly isolated LC indicate upregulation of a…
Cytokines and their effects on maturation, differentiation and migration of dendritic cells.
1996
In this review the role of cytokines in the maturation and migration of phenotypically and functionally diverse dendritic cell (DC) subpopulations is discussed and their role in the progress of differentiation from bone marrow progenitors to lymphoid DC is described. GM-CSF is the most important cytokine for the development of functional DC and acts in concert with a varying mixture of other cytokines such as IL-4, IL-1 and TNF-α to direct the development of individual DC subpopulations.
FACIT collagen (1α-chain) is expressed by hemocytes and epidermis during the inflammatory response of the ascidian Ciona intestinalis
2007
Based on previous cloning and sequencing study, real-time PCR and in situ hybridization assays of the inflamed body wall of LPS-injected Ciona intestinalis showed the enhanced gene expression of a collagen with FACIT structural features (Ci-type IX-Col 1alpha-chain). By using specific antibodies raised against an opportunely chosen Ci-type IX-Col synthetic peptide, the fibroblast property of hemocytes challenged in vitro with LPS (at 4h) was displayed by flow cytometry, while immunocytochemistry identified hemocytes with large granules (morula cells) as collagen-producing cells. Hemocyte lysate supernatant analyzed in immunoblotting contained a 60 kDa band identifiable as 1alpha-chain-Ci-ty…
Compartmentalized production of CCL17 in vivo: strong inducibility in peripheral dendritic cells contrasts selective absence from the spleen.
2003
Dendritic cells (DCs)(*) fulfill an important regulatory function at the interface of the innate and adaptive immune system. The thymus and activation-regulated chemokine (TARC/CCL17) is produced by DCs and facilitates the attraction of activated T cells. Using a fluorescence-based in vivo reporter system, we show that CCL17 expression in mice is found in activated Langerhans cells and mature DCs located in various lymphoid and nonlymphoid organs, and is up-regulated after stimulation with Toll-like receptor ligands. DCs expressing CCL17 belong to the CD11b(+)CD8(-)Dec205(+) DC subset, including the myeloid-related DCs located in the subepithelial dome of Peyer's patches. CCL17-deficient mi…