Keratinocytes cells

Keratinocyte proliferation is central to the clinical presentation of psoriasis. Keratinocytes are skin cells producing keratin which act as a skin barrier. Increased keratinocyte cell turnover (hyperkeratosis) results in the characteristic thick scaly skin lesions seen in patients with psoriasis.10,11 Hyperkeratosis results from immune derangements. 

Shvedova, A.A., Castranova, V., Kisin, E.R., Schwegler-Berry, D., Murray, A.R., Gandelsman, V.Z., Maynard, A., and Baron, P. (2003) Exposure to carbon nanotube material assessment of nanotube cytotoxicity using human keratinocyte cells. Journal of Toxicology and Environmental Health, Part A Current Issues, 66 (20), 1909-1926. 

Van Och, F.M. et al., Assessment of potency of allergenic activity of low molecular weight compounds based on IL-1 alpha and IL-18 production by a murine and human keratinocyte cell line, Toxicology, 210, 95, 2005. 

Gupta, A., Rosenberger, S. F., and Bowden, G. T., Increased ROS levels contribute to elevated transcription factor and MAP kinase activities in malignantly progressed mouse keratinocyte cell lines, Carcinogenesis, 20, 2063, 1999. 

Shvedova AA, Castranova V, Kisin ER, Schwegler-Berry D, Murray AR, Gandelsman VZ, Maynard A, Baron P (2003) Exposure to carbon nanotube material Assessment of nanotube cytotoxicity using human keratinocyte cells. J. Toxicol. Environ. Flealth A 66 1909-1926. 

Boukamp, P., R. T. Petrussevska, D. Breitkreutz, J. Homung, A. Markham, and N. E. Fusenig. 1988. Normal keratinization in a spontaneously immortalized aneuploid human keratinocyte cell line. J Cell Biol 106(3) 761-71. 

O Driscoll KR, Madden PV, Christiansen KM, Viage A, Slaga T), Fabbro D, Powell CT. Weinstein IB (1994) Overexpression of protein kinase C beta I in a murine keratinocyte cell line produces effects on cellular growth, morphology and differentiation. Cancer Lett 83 249-259... 

Currie LJ, Martin R, Sharpe JR, James SE (2003) A comparison of keratinocyte cell sprays with and without fibrin glue. Bums 29(7) 677-685... 

Simon, M., and Green, H. (1984). Participation of membrane-associated proteins in the formation of the cross-linked envelope of the keratinocyte. Cell 36, 827-834. 

Hudson LG, Toscano WA Jr, Greenlee WF. 1985. Regulation of epidermal growth factor binding in human keratinocyte cell line by 2,3,7,8-tetrachlorodibenzo-p-dioxin. Toxicol Appl Pharmacol 77 251-259. 

Thus, external forces applied to the epidermis and/or internal forces present in dermis are transmitted through the cornified layer and lead to stretching of keratinocyte-keratinocyte cell junctions and the epidermal-dermal junction. These forces appear to be transmitted between epithelial cells via cadherins and may result in activation of secondary messengers which alter gene expression and protein synthesis. 

Living, bi-layered skin substitute containing type 1 bovine collagen Extracted and purified from bovine tendons and viable allogeneic human fibroblast and keratinocytes cells isolated from human infant foreskin... 

Doxycycline inhibits the detachment of SM-exposed HaCaT cells in culture from the growth substrate. However, analysis of the metabolic activity of the adherent cells reveals that doxycycline treatment does not maintain cell viability. It is suggested that doxycycline and other matrix metalloprotease inhibitors may have a role to play in therapeutic intervention against SM, only as a combination therapy (Lindsay et al, 2007). Human keratinocyte cell lines were pretreated with mixtures of methenamine and glutathione prior to SM exposure. Though it is possible to protect the cell cultures from the toxic effects of SM, it will be effective only as a pretreatment (Smith et al, 1997). 

Cowan, F.M., Broomfield, C.A., Smith, W.J. (2002). Suppression of sulfur mustard-increased IL-8 in human keratinocyte cell cultures by serine protease inbibitors implications for toxicity and medical countermeasures. Cell Biol. Toxicol. 18 175-80. 

Hu P, Berkowitz P, Madden VJ, Rubenstein DS. Stabilization of plakoglobin and enhanced keratinocyte cell-cell adhesion by infra- 37. cellular 0-glycosylation. J. Biol. Chem. 2006 281 12786-12791. 

Limat A, Breitkreutz D, Hunziker T, Klein CE, Nozer F, Fusenig NE Braathen LR (1994) Outer root sheath (ORS) cells organize into epidermoid cyst-like spheroids when cultured inside Matrigel a light-microscope and immunohistological comparison between human ORS cells and interfoUicular keratinocytes. Cell and Tissue Research 275 169-176. 

Finally, cell culture studies are often used to assess direct cutaneous toxicity to skin cells such as keratinocytes. As discussed above, this can be used to define if a potential topical chemical that penetrates the skin can cause epidermal cell dysfunction. However, systemically administered chemicals can also distribute to skin and modify keratinocytes cell function. Damage to skin, especially if the mechanism of action is immunological, does not require topical exposure. 

Oddi S, Bari M, Battista N, Barsacchi D, Cozzani I, Maccarrone M (2005) Confocal microscopy and biochemical analysis reveal spatial and functional separation between anandamide uptake and hydrolysis in human keratinocytes. Cell Mol Life Sci 62 386-395... 

NF-kB regulates many genes involved in inflammation, such as inducible nitric oxide synthase (iNOS), proinflammatory cytokines, IL-1, mmor necrosis factor-alpha (TNF-a), IL-6, chemokine, IL-8, E-selectin, vascular cell adhesion molecule 1 (ICAM-1), and granulocyte-macrophage colony stimulating factor (GM-CSF) (Brennan et al., 1995 Akira and Kishimoto, 1997 Bames and Adcock, 1998 Rahman and MacNee, 1998 McClintock et al., 2002). Arroyo et al. (2000) found a dose-dependent increase in TNF-a, IL-6, and interleukin-1-beta (IL-1-beta) in SM-treated human keratinocyte cells. 

Farkas A, Kemeny L, Szony BJ, et al. Dithranol upregulates IL-10 receptors on the cultured human keratinocyte cell hne HaCaT. Inflamm Res 2001 50 44 9. 

Keratinocyte—Cell of the epidermis that produces keratin. 

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