interleukin-8 and involucrin

Recent in vivo studies have demonstrated involvement of the histamine H4 receptor in pruritus and skin inflammation. We previously reported that an H4 receptor antagonist attenuated scratching behaviour and improved skin lesions in an experimental model of atopic dermatitis. We also reported the expression of the H4 receptor in human epidermal tissues. In this study, we investigated the expression of H4 receptor mRNA and the function of the receptor in a culture system that mimics in vivo inflammation on the HaCaT human keratinocyte cell line. Increased expression of the H4 receptor was observed in HaCaT cells following differentiation. Treatment of HaCaT cells with histamine and TNFα enhanced the mRNA expression of interleukin (IL)-8. These increases in expression were significantly inhibited by the H4 receptor antagonist JNJ7777120. Our results indicate that IL-8 mRNA expression might be enhanced by histamine and TNFα via H4 receptor stimulation in keratinocytes.

Topics: Cell Differentiation; Cell Line; Gene Expression Regulation; Histamine; Humans; Indoles; Interleukin-8; Keratinocytes; Piperazines; Protein Precursors; Receptors, G-Protein-Coupled; Receptors, Histamine; Receptors, Histamine H4; RNA, Messenger; Tumor Necrosis Factor-alpha

In the present study, the inhibitory effect of arazyme on allergic inflammation was investigated by evaluating the alteration of cytokine production and expression of skin barrier proteins in immune and HaCaT human keratinocyte cells. THP‑1 human monocytic and EoL‑1 human eosinophilic cells were treated with Dermatophagoides pteronissinus extract (DpE). Monocyte chemotactic protein‑1 (MCP‑1)/CCL2, interleukin (IL)‑6 and IL‑8 increased following DpE treatment and arazyme significantly blocked the increase of MCP‑1, IL‑6 and IL‑8 expression in cell types. Secretion of MCP‑1, IL‑6 and IL‑8 induced by lipopolysaccharide in THP‑1 cells was also inhibited by arazyme treatment. Arazyme inhibited the secretion of IL‑6 and IL‑8 due to phorbol 12‑myristate 13‑acetate and calcium ionophores in human mast cells. Arazyme blocked the secretion of thymus and activation‑regulated chemokine (TARC)/CCL17, MCP‑1, IL‑6 and IL‑8 due to tumor necrosis factor‑α (TNF‑α) and interferon‑γ (IFN‑γ) in HaCaT cells. TNF‑α and IFN‑γ suppressed the expression of skin barrier proteins, including filaggrin, involucrin and loricrin. By contrast, arazyme increased the expression of filaggrin, involucrin and loricrin. These results may contribute to the development of a therapeutic drug for the treatment of allergic diseases, including atopic dermatitis.

Topics: Bacterial Proteins; Cell Line; Chemokine CCL2; Cytokines; Enterobacteriaceae; Eosinophils; Filaggrin Proteins; Gene Expression Regulation; Humans; Interleukin-8; Intermediate Filament Proteins; Keratinocytes; Membrane Proteins; Metalloproteases; Monocytes; Protein Precursors; Skin; Up-Regulation

Our previous gene expression analysis suggested that conjunctival epithelial cells of Sjögren's syndrome (SS) are inclined to hyper-proliferation and keratinisation status. The goal of this study is to elucidate whether such pathological situations really exist in the conjunctival epithelium of SS. Also, involvement of inflammatory cytokines in this disease was investigated. Conjunctival tissues or cells obtained from 12 SS patients and 13 normal subjects were subjected to indirect immunostaining to analyse expression of transglutaminase 1 (TGase1), involucrin, keratins 1, 4, 10 and 13. The number of proliferative cells was also analysed by immunostaining of Ki67 antigen. Additionally, changes in gene expression of TGase1 and involucrin after stimulation by IL-1 or IFN-gamma were quantified by real-time RT-PCR. TGase1 and involucrin were up-regulated in the conjunctival epithelium of SS patients. Although not statistically significant, Ki67 positive proliferative cells were slightly increased in SS patients. IFN-gamma stimulation significantly up-regulated TGase1 and unexpectedly repressed involucrin gene expression. IL-1 did not render any significant changes in the expression of these genes. These results suggest the existence of pathological keratinisation in the conjunctival epithelium of SS and also support our hypothesis that inflammatory cytokines may be involved in the ocular surface pathological changes in SS.

Topics: Aged; Biomarkers; Case-Control Studies; Cell Proliferation; Cells, Cultured; Conjunctiva; Epithelium; Female; Fluorescent Antibody Technique, Indirect; Gene Expression; HLA-DR Antigens; Humans; Interferon-gamma; Interleukin-1; Interleukin-8; Keratins; Middle Aged; Protein Precursors; Reverse Transcriptase Polymerase Chain Reaction; Sjogren's Syndrome; Statistics, Nonparametric; Transglutaminases; Up-Regulation

Gingival epithelial cells are a central component of the barrier between oral microflora and internal tissues. Host responses to periodontopathic bacteria and surface components containing fimbriae are thought to be important in the development and progression of periodontal diseases. To elucidate this mechanism, we established immortalized human gingival epithelial cells (HGEC) that were transfected with human papillomavirus. HGEC predominantly expressed Toll-like receptor (TLR) 2, but not TLR4 or CD14. They also induced interleukin-8 (IL-8) production when stimulated with Porphyromonas gingivalis fimbriae and Staphylococcus aureus peptidoglycan, but not Escherichia coli-type synthetic lipid A. Furthermore, an active synthetic peptide composed of residues 69 to 73 (ALTTE) of the fimbrial subunit protein, derived from P. gingivalis and similar to a common component of cell wall peptidoglycans in parasitic bacteria, N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP), significantly induced IL-8 production and NF-kappaB activation in HGEC, and these cytokine-producing activities were augmented by a complex of soluble CD14 and lipopolysaccharide-binding protein (LBP). IL-8 production in HGEC stimulated with these bacterial components was clearly inhibited by mouse monoclonal antibody to human TLR2. These findings suggest that P. gingivalis fimbrial protein and its active peptide are capable of activating HGEC through TLR2.

Topics: Bacterial Proteins; Drosophila Proteins; Epithelial Cells; Fimbriae, Bacterial; Gingiva; Humans; Interleukin-8; Keratins; Lipopolysaccharide Receptors; Membrane Glycoproteins; NF-kappa B; Oligopeptides; Peptide Fragments; Protein Precursors; Receptors, Cell Surface; Signal Transduction; Toll-Like Receptor 2; Toll-Like Receptor 4; Toll-Like Receptors

The biologically active vitamin D analog calcipotriol is effective and safe in the topical treatment of psoriasis, but its exact mechanism of action is unknown.. We investigated expression of 1,25-dihydroxyvitamin D3 receptors, markers for inflammation (CD1a, CD4, CD8, CD11b, CD15; NAP-1/interleukin-8; 55 kd tumor necrosis factor-receptor; intercellular adhesion molecule-1; HLA-DR), proliferation (proliferating cell nuclear antigen, Ki-67), and differentiation (transglutaminase K; involucrin; cytokeratin 16) in psoriatic skin during topical calcipotriol treatment.. For immunohistochemical staining we used the labeled avidin-biotin technique on cryostat-cut sections.. We found a significant increase of 1,25-dihydroxyvitamin D3 receptor expression in epidermal basal keratinocytes of lesional psoriatic skin during calcipotriol treatment. In all patients analyzed, effects on proliferation and differentiation of epidermal keratinocytes were stronger than effects on dermal inflammation. Effects on inflammation were more pronounced in the epidermal than in the dermal compartment.. Our findings indicate that analogs of 1,25-dihydroxyvitamin D3 upregulate their corresponding receptor in human keratinocytes in vivo. This mechanism may be important in the therapeutic efficacy of vitamin D analogs in psoriasis. The differential therapeutic effects in the epidermal and dermal skin compartments may be due to a reduced bioavailability of calcipotriol in the dermal compartment.

Topics: Administration, Cutaneous; Antigens, CD; Antigens, CD1; Biological Availability; Calcitriol; CD11 Antigens; CD4 Antigens; CD8 Antigens; Cell Differentiation; Cell Division; Dermatologic Agents; Epidermis; Gene Expression Regulation; HLA-DR Antigens; Humans; Immunoenzyme Techniques; Immunohistochemistry; Intercellular Adhesion Molecule-1; Interleukin-8; Keratinocytes; Keratins; Lewis X Antigen; Male; Proliferating Cell Nuclear Antigen; Protein Precursors; Psoriasis; Receptors, Calcitriol; Receptors, Interleukin; Receptors, Interleukin-8A; Receptors, Tumor Necrosis Factor; Skin; Transglutaminases; Tumor Necrosis Factor-alpha; Up-Regulation

The potent calciotropic hormone calcitriol (1,25-dihydroxyvitamin D3, 1,25(OH)2D3) has been shown to be very effective and safe in the topical treatment of psoriasis. In vitro, 1,25(OH)2D3 inhibits proliferation and stimulates differentiation of human keratinocytes. Increasing evidence suggests an immunoregulatory function of this potent steroid hormone. To further characterize the biological effects of topical calcitriol treatment in psoriasis, we have analyzed immunohistochemically the expression of markers for epidermal proliferation (proliferating cell nuclear antigen=PCNA) and differentiation (transglutaminase K, involucrin, cytokeratin 16), as well as inflammation (CD1a, 55 kDa TNF-receptor, NAP-1/IL-8) in calcitriol-treated psoriatic skin in situ. Our findings strongly support the hypothesis that calcitriol modulates keratinocyte proliferation/differentiation as well as inflammation in human skin in vivo. The immunoreactivity of markers for epidermal proliferation and differentiation, as well as of CD1a and NAP-1/IL-8, changed after 8 weeks of calcitriol treatment almost completely to the pattern characteristic for non-lesional psoriatic skin, while a large number of 55 kDa TNF-receptor positive cells could be found in the dermal compartment.

Topics: Administration, Topical; Antigens, CD1; Calcitriol; Cell Differentiation; Cell Division; Humans; Immunohistochemistry; Interleukin-8; Keratinocytes; Keratins; Proliferating Cell Nuclear Antigen; Protein Precursors; Psoriasis; Receptors, Tumor Necrosis Factor; Skin; Transglutaminases