title: Differentiation-regulated expression of Toll-like receptors 2 and 4 in HaCaT keratinocytes.
abstract: Toll-like receptors (TLRs) play an important role in the recognition of pathogens in keratinocytes. In this study, we investigated whether the differentiation state of HaCaT keratinocytes correlates with the expression of TLR2 and TLR4 genes. The expression levels of TLR2 and TLR4 in a HaCaT differentiation model system were determined using quantitative real-time RT-PCR (Q-RT-PCR) and flow cytometry. The progression of keratinocyte differentiation was monitored by determining the level of involucrin gene expression using Q-RT-PCR. The expression levels of TLR2 and TLR4 increased with the stage of differentiation and there were strong correlations between the expression level of the involucrin gene and those of the TLR2 gene ( r=0.809, P<0.0001) and the TLR4 gene ( r=0.568, P<0.02). Increased cell surface expression of TLR2 and TLR4 was also found in differentiated HaCaT keratinocytes by flow cytometric analysis. Our findings suggest that upregulation of TLR expression during differentiation in keratinocytes could be a part of the differentiation process of keratinocytes and could have biological significance in protecting skin against microbes.
authors.affiliation: Department of Dermatology and Allergology, University of Szeged, Korányi fasor 6., H-6701, Szeged, Hungary. andor@mail.derma.szote.u-szeged.hu
authors.forename: Andor
authors.initials: A
authors.lastname: Pivarcsi
authors.forename: Andrea
authors.initials: A
authors.lastname: Koreck
authors.forename: Laszlo
authors.initials: L
authors.lastname: Bodai
authors.forename: Márta
authors.initials: M
authors.lastname: Széll
authors.forename: Csilla
authors.initials: C
authors.lastname: Szeg
authors.forename: Nóra
authors.initials: N
authors.lastname: Belso
authors.forename: Anna
authors.initials: A
authors.lastname: Kenderessy-Szabó
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Bata-Csörgo
authors.forename: Attila
authors.initials: A
authors.lastname: Dobozy
authors.forename: Lajos
authors.initials: L
authors.lastname: Kemény
mesh_terms: D002454:Cell Differentiation / Q000502:physiology; D002460:Cell Line; D000078404:Epidermal Cells; D004817:Epidermis / Q000276:immunology; D015870:Gene Expression / Q000276:immunology; D006801:Humans; D015603:Keratinocytes / Q000166:cytology* / Q000502:physiology*; D008562:Membrane Glycoproteins / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D011956:Receptors, Cell Surface / Q000235:genetics*; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors; D015854:Up-Regulation / Q000276:immunology
chemical_list: D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; C495342:TLR2 protein, human; C495345:TLR4 protein, human; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors