Search results for "HaCaT"
showing 10 items of 29 documents
Enhanced expression of IL-8 in normal human keratinocytes and human keratinocyte cell line HaCaT in vitro after stimulation with contact sensitizers,…
1994
Abstract To investigate the interleukin-8 production of keratinocytes after stimulation in vitro we have used various agents: (i) contact sensi-tizer (2,4-dinitrofiuorobenzene, 3-n-penladecylcatechol); (ii) tolerogen (5-methyl-3-n-pentadecylcatechol); (iii) irritant (sodium lauryl sulfate). Interleukin-8 gene expression was assessed by northern blot hybridization of the total cytoplasmic RNA extracted from subconfluent normal human keratinocyte cultures and the keratinocyte cell line HaCaT using a radiolabeled DNA probe specific for human interleukin-8. Intcrleukin-8 gene expression was markedly increased upon in vitro stimulation after 1-6 h with contact sensitizers, tolerogen and the irri…
Melittin Modulates Keratinocyte Function through P2 Receptor-dependent ADAM Activation
2012
Melittin, the major component of the bee venom, is an amphipathic, cationic peptide with a wide spectrum of biological properties that is being considered as an anti-inflammatory and anti-cancer agent. It modulates multiple cellular functions but the underlying mechanisms are not clearly understood. Here, we report that melittin activates disintegrin-like metalloproteases (ADAMs) and that downstream events likely contribute to the biological effects evoked by the peptide. Melittin stimulated the proteolysis of ADAM10 and ADAM17 substrates in human neutrophil granulocytes, endothelial cells and murine fibroblasts. In human HaCaT keratinocytes, melittin induced shedding of the adhesion molecu…
Preliminary approach to elucidate the role of pigment as a binding site for drugs and chemicals in anagen hair: differential uptake of 3 H-haloperido…
2002
A striking difference was observed for cellular-bound drug in HaCaT and Sk-Mel-1 cells for a fixed drug exposure time of 72 h and varying 3H-haloperidol concentrations in the culture media. Drug uptake was dependent on drug concentration and linearly correlated for both the non-pigment- and the pigment-producing cells which however was different in magnitude. In an additional investigation the time course of drug uptake during 3H-haloperidol exposure (400 pmol/ml; 28 days) revealed increasing drug concentrations in the Sk-Mel-1 population, whereas drug concentrations in the keratinocytes reached a plateau within a short time period. In contrast to the HaCaT cells no tendency to saturation w…
The cell adhesion domain of type XVII collagen promotes integrin-mediated cell spreading by a novel mechanism.
2001
Type XVII collagen (BP180) is a keratinocyte transmembrane protein that exists as the full-length protein in hemidesmosomes and as a 120-kDa shed ectodomain in the extracellular matrix. The largest collagenous domain of type XVII collagen, COL15, has been described previously as a cell adhesion domain (Tasanen, K., Eble, J. A., Aumailley, M., Schumann, H., Baetge, J, Tu, H., Bruckner, P., and Bruckner-Tuderman, L. (2000) J. Biol. Chem. 275, 3093-3099). In the present work, the integrin binding of triple helical, human recombinant COL15 was tested. Solid phase binding assays using recombinant integrin alpha(1)I, alpha(2)I, and alpha(10)I domains and cell spreading assays with alpha(1)beta(1)…
Different integrins mediate cell spreading, haptotaxis and lateral migration of HaCaT keratinocytes on fibronectin
2000
Collaborative role of various fibronectin-binding integrins (alpha5beta1, alphavbeta1 and alphavbeta6) as mediators of cell adhesion and migration on fibronectin was studied using cultured HaCaT keratinocytes. This cell line spontaneously expressed all three fibronectin-binding integrins. In addition, the expression of alphavbeta6 integrin was strongly and specifically upregulated by transforming growth factor-beta1 (TGFbeta1) whereas the amount of other integrins remained practically unchanged on the cell surface. Adhesion, spreading and motility of HaCaT keratinocytes on fibronectin were promoted by TGFbeta1. Based on antibody blocking experiments, both untreated and TGFbeta1-treated HaCa…
The Influence of Adalimumab and Cyclosporine A on the Expression Profile of the Genes Related to TGFβ Signaling Pathways in Keratinocyte Cells Treate…
2020
Background. In the treatment of moderate to severe psoriasis, cyclosporine A (CsA) conventional therapy is used and biological, anti-cytokine treatment using, for example, anti-TNF drug—adalimumab. Aim. This study aimed at investigating the effect of CsA and adalimumab on the profile of mRNAs and protein expression associated with transforming growth factor β (TGFβ) pathways in human keratinocyte (HaCaT) culture previously exposed to lipopolysaccharide (LPS). Materials and Methods. HaCaT culture was exposed to 1 ng/ml LPS for 8 hours+8 μg/ml adalimumab for 2, 8, and 24 hours or 1 ng/ml LPS for 8 hours+100 ng/ml CsA for 2, 8, and 24 hours and compared to the control culture. Sulphorodamine B…
In contrast to their murine counterparts, normal human keratinocytes and human epidermoid cell lines A431 and HaCaT fail to express IL-10 mRNA and pr…
1997
Abstract In mice, keratinocyte-derived IL-10 is up-regulated by ultraviolet-B (UVB) radiation and plays a major role in UVB-induced immunosuppression. The present study was designed to examine whether a comparable phenomenon can be detected in man. Freshly isolated or cultured normal human keratinocytes (NHK) and keratinocyte cell lines A431 and HaCaT were stimulated with graded doses of UVB (up to 200 J/m2) or with a variety of other stimuli. RNA was extracted at various time points post-stimulation and analysed by reverse transcriptase-polymerase chain reaction (RT-PCR) using four different IL-10-specific primer pairs and RNA from monocytes or T cells as positive controls. We failed to de…
Oxidative DNA damage induced by visible light in mammalian cells: extent, inhibition by antioxidants and genotoxic effects
1998
The extent of the indirect DNA damage generated in mammalian cells by visible light because of the presence of endogenous photosensitizers was studied by means of repair endonucleases. In immortalized human keratinocytes (HaCaT cells) exposed to low doses of natural sunlight, the yield of oxidative DNA base modifications sensitive to the repair endonuclease formamidopyrimidine-DNA glycosylase (Fpg protein) generated by this indirect mechanism was 10% of that of pyrimidine dimers (generated by direct DNA excitation). A similar yield of Fpg-sensitive modifications, which include 8-hydroxyguanine, was observed in primary keratinocytes. The relative yield of oxidative base modifications decreas…
Potential Antipsoriatic Avarol Derivatives as Antioxidants and Inhibitors of PGE2 Generation and Proliferation in the HaCaT Cell Line
2004
The synthesis and structure-activity relationships for a series of 14 new avarol derivatives as antioxidants and inhibitors of cell proliferation and PGE(2) generation in human keratinocytes are described. Compound 6 (thiosalicylic derivative) was the most potent inhibitor of superoxide generation in human neutrophils and also potently inhibited PGE(2) generation in the human keratinocyte HaCaT cell line. Compound 7(3'-methylaminoavarone) presented the best antiproliferative profile, by the inhibition of (3)H-thymidine incorporation in HaCaT cells, with potency similar to the reference compound anthralin. None of the avarol derivatives showed any sign of cytotoxicity measured as LDH release…
Preliminary approach to elucidate the role of pigment as a binding site for drugs and chemicals in anagen hairs: pigments as carriers for 3 H-haloper…
2002
In view of the melanin-binding characteristics of haloperidol and its differential uptake by pigment- and non-pigment-producing cells, a co-culture of HaCaT with Sk-Mel-1 cell lines was performed to investigate whether melanosomes act as carriers for drug molecules associated with the pigments. Initially, HaCaT and Sk-Mel-1 cells were separately cultivated in the presence of 3H-haloperidol (400 pmol/ml medium ) for 28 days followed by subsequent co-cultivation in the absence of 3H-haloperidol for 5 days. The transfer of pigments into the keratinocytes during co-culture was confirmed by transmission electron microscopy. After the co-culture experiments a striking increase (or = 50%) of 3H-ha…