Data/hora: 05/06/2024 02:17:35

Provedor de dados: 	17	
País: 	United Kingdom	
Título: 	Keratinocytes from human skin respond as typical immune cells after the stimulation with _Trichophyton rubrum_	
Autores: 	Alfonso E. Islas-Rodr&amp;#xed;guez; Luz A. Garc&amp;#xed;a-Madrid.	
Data: 	2007-09-06	
Ano: 	2007	
Palavras-chave: 	Immunology; Microbiology; Molecular Cell Biology.	
Resumo: 	_Trichophyton rubrum_ is the main agent causing dermatophytosis (1). Keratinocytes are&amp;#xd;&amp;#xa;considered to be the first physical barrier of defense against pathogens (2). But not&amp;#xd;&amp;#xa;only a physical barrier. They recognize antigens through Toll like receptors (TLR) (3).&amp;#xd;&amp;#xa;The activation of this TLR, present on the surface of the keratinocytes, induce the&amp;#xd;&amp;#xa;expression of different pro-inflammatory cytokines, co-stimulatory molecules and&amp;#xd;&amp;#xa;antimicrobial peptides such as [beta]-defensins (4).&amp;#xd;&amp;#xa;The main objective of this work is to determine if lipopolysaccharides of G &amp;#x2013; bacteria&amp;#xd;&amp;#xa;(LPS), lipotheichoic acid from G+ bacteria (LTA), and conidias, isolated from _T. rubrum_&amp;#xd;&amp;#xa;were able to activate the expression of TLR2 and TLR6 on the cell surface of a primary&amp;#xd;&amp;#xa;culture of human keratinocytes through Flow cytometry. Furthermore we are looking for&amp;#xd;&amp;#xa;the presence of [beta]-defensins 1 and 2, IL-1b and IL-8 in the supernatant, of the above&amp;#xd;&amp;#xa;mentioned culture of cells, by Western blot.&amp;#xd;&amp;#xa;From the flow cytometry data, the preliminary results showed an important dispersion&amp;#xd;&amp;#xa;in terms of proliferation, increase in size and granularity of keratinocytes, from primary&amp;#xd;&amp;#xa;cultures of skin from healthy donors, stimulated 6 hours with conidias of _T. rubrum_, and&amp;#xd;&amp;#xa;LTA, but not when non stimulated, or stimulated with LPS (Fig 1).&amp;#xd;&amp;#xa;When keratinocytes from primary cultures of skin from healthy donors were cultivated&amp;#xd;&amp;#xa;48 hours, it was found dispersion in terms of proliferation, increase in size and&amp;#xd;&amp;#xa;granularity when stimulated with conidias of _T. rubrum_, and LPS but not when non&amp;#xd;&amp;#xa;stimulated, or stimulated with LTA (Fig 2).&amp;#xd;&amp;#xa;The keratinocytes expressed increased levels of TLR2 and TLR6 when were&amp;#xd;&amp;#xa;stimulated with LTA and less to _T. rubrum_, in the 6 hours cultures, but this last cells still&amp;#xd;&amp;#xa;showed increased size (Fig 3).&amp;#xd;&amp;#xa;The Keratinocytes expressed increased levels of TLR2 in the 48 hours cultures when&amp;#xd;&amp;#xa;were stimulated with LPS and _T. rubrum_.(Fig 4)&amp;#xd;&amp;#xa;Besides, [beta]-defensin-2 was detected in the supernatant of cultures of keratinocytes&amp;#xd;&amp;#xa;stimulated with LPS (Fig 5).&amp;#xd;&amp;#xa;It can preliminary be concluded that keratinocytes from primary cultures of human skin from healthy donors, are cells that respond as typical immune cells, after stimulation&amp;#xd;&amp;#xa;with _T. rubrum_, LTA and LPS in different conditions, and that this mechanism may be&amp;#xd;&amp;#xa;very important, for the protection of local environment. &amp;#xd;&amp;#xa;&amp;#xd;&amp;#xa;References&amp;#xd;&amp;#xa;1.- Arenas R., Dermatofitosis en M&amp;#xe9;xico. Rev Iberoam Micol 2002; 19: 63-67.&amp;#xd;&amp;#xa;2.- Kupper T. and Fuhlbrigge R. Immune surveillance in the skin: mechanims and clinical consecuences.&amp;#xd;&amp;#xa;Nat Rev Immunol 2004; 4: 211-222&amp;#xd;&amp;#xa;3.- K&amp;#xf4;llish G., Naderi B., Voelcker V., Wallich R., Behrendt H., Ring J., Bauer S., Jacob T., Mempel M. and&amp;#xd;&amp;#xa;Olelrt M. Various members of the Toll-Like receptor family contribute to the innate immune response of&amp;#xd;&amp;#xa;human epidermal keratinocytes. Immunology 2005; 114: 531-541.&amp;#xd;&amp;#xa;4.- Akira, S. and Takeda K. 2004. Toll-like Receptor Signalling. Nature Reviews Immunology 4:499-511.	
Tipo: 	Manuscript	
Identificador: 	http://precedings.nature.com/documents/930/version/1

oai:nature.com:10101/npre.2007.930.1

http://hdl.handle.net/10101/npre.2007.930.1	
Fonte: 	Nature Precedings	
Fonte: 	Creative Commons Attribution 3.0 License