title: Expression of Toll-like receptors in verruca and molluscum contagiosum.
abstract: Recent studies indicate that several Toll-like receptors (TLRs) are implicated in recognizing viral structures and instigating immune responses against viral infections. The aim of this study is to examine the expression of TLRs and proinflammatory cytokines in viral skin diseases such as verruca vulgaris (VV) and molluscum contagiosum (MC). Reverse transcription-polymerase chain reaction and immunostaining of skin samples were performed to determine the expression of specific antiviral and proinflammatory cytokines as well as 5 TLRs (TLR2, 3, 4, 7, and 9). In normal human skin, TLR2, 4, and 7 mRNA was constitutively expressed, whereas little TLR3 and 9 mRNA was detected. Compared to normal skin (NS), TLR3 and 9 mRNA was clearly expressed in VV and MC specimens. Likewise, immunohistochemistry indicated that keratinocytes in NS constitutively expressed TLR2, 4, and 7; however, TLR3 was rarely detected and TLR9 was only weakly expressed, whereas 5 TLRs were all strongly expressed on the epidermal keratinocytes of VV and MC lesions. In addition, the mRNA expression of IFN-beta and TNF-alpha was upregulated in the VV and MC samples. Immunohistochemistry indicated that IFN-beta and TNF-alpha were predominantly localized in the granular layer in the VV lesions and adjacent to the MC bodies. Our results indicated that VV and MC skin lesions expressed TLR3 and 9 in addition to IFN-beta and TNF-alpha. These viral-induced proinflammatory cytokines may play a pivotal role in cutaneous innate immune responses.
authors.affiliation: Department of Dermatology, College of Medicine, The Catholic University of Korea, Kangnam St. Mary's Hospital, 505 Banpo-dong, Seocho-gu, Seoul, Korea.
authors.forename: Ja Kyung
authors.initials: JK
authors.lastname: Ku
authors.forename: Hyun Jo
authors.initials: HJ
authors.lastname: Kwon
authors.forename: Mi-Yeon
authors.initials: MY
authors.lastname: Kim
authors.forename: Hoon
authors.initials: H
authors.lastname: Kang
authors.forename: Peter I
authors.initials: PI
authors.lastname: Song
authors.forename: Cheryl A
authors.initials: CA
authors.lastname: Armstrong
authors.forename: John C
authors.initials: JC
authors.lastname: Ansel
authors.forename: Hyung Ok
authors.initials: HO
authors.lastname: Kim
authors.forename: Young Min
authors.initials: YM
authors.lastname: Park
mesh_terms: D016207:Cytokines / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007249:Inflammation; D016899:Interferon-beta / Q000096:biosynthesis; D015603:Keratinocytes / Q000166:cytology; D008954:Models, Biological; D008976:Molluscum Contagiosum / Q000378:metabolism*; D051196:Toll-Like Receptor 3 / Q000096:biosynthesis; D051217:Toll-Like Receptor 9 / Q000096:biosynthesis; D051193:Toll-Like Receptors / Q000096:biosynthesis*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D014860:Warts / Q000378:metabolism*
chemical_list: D016207:Cytokines; C495344:TLR3 protein, human; C495371:TLR9 protein, human; D051196:Toll-Like Receptor 3; D051217:Toll-Like Receptor 9; D051193:Toll-Like Receptors; D014409:Tumor Necrosis Factor-alpha; D016899:Interferon-beta