Abstracts JSIDICSID Joint Meeting

ORAL PRESENTATIONS

83

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COMBINATIONTREATMENTS WITH ULTRAVIOLET B AN@ INTERLEUKIN- la DRAMATICALLY INCREASE TUMOR NECROSIS FACTOR-a PRODUCTlON IN HUMAN DERMAL FIBROBLASTS. fIiroshi Fuiisawa. w

‘v” -and Division of Dermatology, Sunnybrook Health Science Centre, University of Toronto, Toronto, Canada.

Ultraviolet B (UVB) is known 10 induce cylokine synthesis m the skin. Cytokines act in a cascade fashion and can have synergistic or antagonistic actions on re.gulstion of other cytokines. In this study, we examined the potential synergy ix&en UVB and in&eukin-la (IL-la) 0. cylokine production by human bennal fibrobIns& UVB irradiation (ZOO I/m’) or IL-la (IO w/ml) indeoendentlv induced small amoonts of tumor necro& facto& (TNF-aj (<Z?pg/ml) f&n horn& dermal tibroblasu. However, combined treatments with UVB i&&ion (ZOO I/m’) and IL- lcx (IO ne/mll induced 30-40 fold (un 10 800 oe/mll hieher levels of TNF-a than foodd in &he; UVB or IL-la treau&t alone &-ass&d by ELISA. This synergic effect was also observed at a message level. In order to obtain maximum synerg,slic effects, it was necessary 10 add IL-la within 3 hours after UVB irradiation. UVB is capable of causing release of IL-la from human keradnocytes. While most UVB is filtered oo, by epidanis. approximately 10% of incident UVB penetrates to the level of dermal tibroblasu. Thus, UVB may act in a cascade fashion to induce inflammation by initial release of keratinocytes IL-la which [hen synergizes with UVB on human dennal fibrohlasu to significantly increase TNF-a production

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IL-I. BUT NOT TNF-a, SYNERGISTICALLY UP-REGULATES THE GM-CSF- INDUCED 87-l EXPRESSION OFMURINELANGERHANS CELLS. M. Funre, C. H. Char@, and K. Tamakil. Department of Dermatology, Tokyo University Branch Hospital, *Department of Dermatology, Kaohsiung Medical College. #Department of Dennatology,Umve,wy of Tokyo

Epidermal Lmgerhans cells (LC) express several co-sumulatory mdecules such as 87188 1, wbch has been ,mplwted as one of the imponan, detemunants for potent anngen presenting function of LC. Recent studies have shown that 871881 antigens cornprize three disunct molecules termed 87-l. B7-2, and B7-3. F’rwoos studies have revealed that the phenotypx and funcdonrd properties of LC are encxmwsly affected by YWOUS cylokines mcltimg granulocyte-maaophage cdony somulating facta (GM- CSF), ~nterleuk~n-I (IL-l), and tumor necros,s factor a (TNF-a) derived from sorroundmg keradnccytes. We have examined the effects of various cytokines on Le B7- 1 expressmn of munne LC. OH ep~dennal cells (2x106 - 3x106 cells/ml/well) were cultured m 24-well plate wth medium onlv. GM-CSF (0.05% U/ml). TNF-a (IO-ICC0

U/ml).lL-la(l-lOU/ml),orIL-le(0.1.IOU/ml) forZ4hor72hat37oC.The nonadherent cell population was harvested, and double-smmed with anti-B7-l and an,]-l- Ak anhbcdies. then-was analyzed by flow cyfometry. The expression of 87-l was slgnificandy upregulated by GM-CSF,Ti+-a. IL-la, or IL-1B ma dose-dependent manner. The upregulatory effect of GM-CSF was mast potent, and as low as 0.05 U/ml of GM-CSF sigmficardly enhanced the 87-l expression. None of the cytokines reprcdwbly affecti the expression of I-A. Moreover, ILI, but no,TNFa, synergstically upregulated Ihe GM-CSF-induced 87-1 expression of munne LC. These results suggest that TNF-a may exert u different stlmolus to LC compared to GM-CSF or IL-I.

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6 DETECTtON OF UNIDUE GENES IN LCCAlJZED SCLERDDERMA FtBFtOBLASTS BY THE mRNA DlFFERENTtAL DISPLAY STRATEGY. M. Ueki. Dept. of Dermatology and *Plastic 8 Reconstructive Surgery, Kawasaki Medimt School, tirashiki, Japan. --

Localized scleroderma is an Idiopathic dir charactswod by an accumulation d the extracellular matrix in dermis. Lesional skin fibroblasts have been believed to play a crucial role in the disease development. Indeed, abnormal expressions of several extracellular matrix genes in lesional fibroblasts have been observed. howwor. the all-tin machinery of b fun&n is tilt unctoar. To address molecular mechanisms of changes in fibroblasts, w8 employed P mRNA differential display which is a novel gene sublraclon strategy. Total RNA6 of cutlured derd ItbmMasN de&ad lrom involved and uninvolved Iksions of Mcwhea patients (n=4) ware exiracted Poly-A RNAs we wnwrted into cDNA, amplitied by a polmerass chain reaction using 20 wts of primers. then analyzed on a sequencing get. In patient 1, 30 altered clones, including 3’ l-ion of NFrB DNA binding subuntt, were detected in involved fibmblasls 88 canpared to uninv&& Sbrobtasts. In addition, three d these r,&nas. designated as 41FA42. 41FTll. and 41FG42. showed altered expression also in patients 2 and 4. Furthermore. a DNA sequonc~ analysis exhibit& sQnificant segment similarittt to: 0. cuniculw sarmlemmat associated protein-3 (41FTli), Human vitamin D binding protein (41 FA42), and Yq43bQ7sl Homo sapiens cDNA clone (4iFG42). To analyze dot& ot tha%s genes. loll-length clonmg and tissue in silu hybridizafion tilt be pursed. This approach may lead us to identii gene(s) associated with the wdurs of the disease.