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203 Inhibition of Human Cyclooxygenase-1 by DermatophagoidesAllergenic Extracts

M. Sanchez-Borges1, M. Ouellet2, M. Percival3, A. Capriles-Hulett1, F.Caballero-Fonseca1; 1Allergy and Immunology, Centro Médico-DocenteLa Trinidad, Caracas, VENEZUELA, 2Merck Frosst Canada & Co., Kirk-land, PQ, CANADA, 3Allergy and Immunology, Merck Frosst Canada &Co., Kirkland, PQ, CANADA.RATIONALE: An increased prevalence of cutaneous NSAID hypersen-sitivity reactions (urticaria and/or angioedema) has been observed inpatients who experience systemic anaphylaxis triggered by mite-contam-inated foods. We have investigated the presence of substances that inhib-it human cyclooxygenases (COX) in Dermatophagoides allergenicextracts.METHODS: The in vitro effects of Dermatophagoides farinae and Der-matophagoides pteronyssinus commercial allergenic extracts on COX-1and COX-2 isoenzymes were studied using recombinant human COX-1and COX-2 microsomal assays.RESULTS: COX-1 enzymatic activity was inhibited by a 2000 AU/mlconcentration of D. farinae and D. pteronyssinus extracts by 76 and 70 %,respectively. On the other hand, both extracts produced a significant acti-vation of COX-2 activity at concentrations above 220 AU/ml.CONCLUSIONS: COX-1 inhibition by mite-derived products may con-tribute to the clinical picture of severe adverse reactions observed in someNSAID-sensitive subjects occurring immediately after oral/GI mucosalexposure to foods contaminated with mites.

204 [Withdrawn]

206 A Comparison of Cytokine Responses in Respiratory SyncytialVirus and Adenovirus Infections In Vitro

J. S. Yoon, M. H. Lee, H. H. Kim, J. T. Kim, J. S. Lee; Department of pedi-atrics, the Catholic University of Korea, Seoul, REPUBLIC OF KOREA.RATIONALE: Respiratory syncytial virus(RSV) and adenovirus(AV)infections are indistinguishable during the acute phases of the diseases.However, long-term prognosis is different. RSV infection is related tolater development of asthma, and AV, mainly AV serotype 3, 7 and 21, isrelated to residual airway damage manifested by bronchiectasis, bronchi-olitis obliterans. We hypothesized that this difference could be partly dueto different immune responses induced by these viruses.METHODS: To test this hypothesis we infected human bronchial epithe-lial cell line BEAS-2B with RSV and AV serotype 3 at the same multi-plicity of infection 1, and then the total RNAs and the supernatants wereobtained at 24 hour. BEAS-2B cells uninfected were used as a control. IL-6, IL-8 and RANTES mRNA expression and protein production weredetermined by RT-PCR and ELISA respectively.RESULTS: BEAS-2B cells showed mRNA expression and production ofIL-6, IL-8, and RANTES constitutively and after RSV or AV infection.The cells infected with RSV showed a significant increase in the produc-tion of IL-6, IL-8, and RANTES protein(P<0.05) and with AV showed asignificant increase in the production of IL-6 and RANTESprotein(P<0.05) but not of IL-8. IL-6, IL-8, and RANTES protein in cellswith RSV infection were significantly higher than those with AV infec-tion(P<0.05).CONCLUSIONS: These results suggest that there may be differentvirus-specific induction of IL-6, IL-8, and RANTES production duringinfection of airway epithelial cells. Because IL-6, IL-8, and RANTES arethe important mediators of airway inflammation, virus-specific inductionof these cytokines may explain the different long-term prognosis of air-way infection with different virus.Funding: the Catholic University of Korea

207 Effect of Macrophage Inflammatory Protein-1� on AirwayInflammation of Asthma in Mouse Model

C. Li, W. Zhang, X. Chen, L. Xie, Q. He, X. Hu, J. Li, M. Li, R. Wu, Z.Zhang; Division of Pulmonology, Yuying Children’s Hospital, WenzhouMedical College, Wenzhou City, Zhejiang, P.R. China., CHINA.RATIONALE: Macrophage inflammatory protein-1� (MIP-1�) isinvolved in airway inflammation of mouse asthma.METHODS: Mouse asthma was established by the ovalbumin (OVA)sensitization/challenge method. Seventy male BALB/C mice were ran-domly divided into control and asthma groups that received vehicle andOVA respectively. At different time points after last challenge, sera andbronchoalveolar lavage fluid (BALF) were collected for MIP-1� proteinlevel determination using ELISA. The total cell counts and cell distribu-tion was also determined in BALF. MIP-1� protein positive cells wereidentified by immunohistochemistry, mRNA by in situ hybridization.RESULTS: At 24 h after last challenge, MIP-1� level in BALF and seraof asthma group (42.9 ± 5.8 pg/ml and 41.7 ± 6.3 pg/ml, n = 10) were sig-nificant higher than control group (20.9 ± 3.8 pg/ml and 22.4 ± 4.3pg/ml,P<0.01). This increase was noticed as early as 3 h after challenge andpeaked at 24 h. Immunohistochemistry showed that MIP-1� positive cellsat the bronchus were elevated in asthma group (26.4 ± 6.2 %) as comparedto control group (10.3 ± 2.5 %, P<0.01). It was mainly expressed inepithelial cells. In situ hybridization showed that MIP-1� mRNA expres-sion around the bronchus of asthma animals (23.9 ± 4.2 %) were signifi-cantly increased when compared to those of control (8.7 ± 1.8 %, P<0.01).Again, they were mainly located within epithelial cells. Result furtherdemonstrates strong correlation between MIP-1� level and the total andpercentage of EOS in BALF.

J ALLERGY CLIN IMMUNOL Abstracts S51VOLUME 115, NUMBER 2

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205 RV1A and dsRNA Highly Induce a Biphasic Expression ofMIP-3�/CCL20 in Human Bronchial Epithelial Cells (hBECs)

J. M. Bellak1, K. Hanson2, R. A. Brockman-Schneider2, H. Dagher2, J. E.Gern2; 1Medicine, University of Wisconsin Hospital & Clinics, Madison,WI, 2Pediatrics, University of Wisconsin Hospital & Clinics, Madison,WI.RATIONALE: MIP-3� (CC family chemokine also known as CCL20) isa potent chemoattractant for naïve dendritic cells and memory lympho-cytes. Rhinovirus infections in human respiratory epithelium were foundto induce CCL20 mRNA by gene expression profiling, and CCL20 secre-tion during the acute phase of an experimental cold. Mechanisms forupregulation of CCL20 by viruses are not well understood.METHODS: To define the mechanisms of CCL20 induction in hBECs,cell monolayers were incubated with RV1A and dsRNA; CCL20 mRNAwas measured by qPCR and protein secretion by ELISA.RESULTS: Analysis of CCL20 mRNA induction by expression profilingand qPCR yielded similar results. hBECs stimulated with RV1A induceda biphasic pattern of CCL20 mRNA (4.9-, 1.9-, and 4.9-fold at 4, 8, and16 hours; p<0.05). dsRNA induced greater amounts of CCL20 mRNA,with a similar pattern (34-, 9.8-, and 49-fold at 4, 8, and 16 hours;p<0.05). Unstimulated hBECs secreted small amounts of CCL20 (224pg/ml after 48 hours incubation), and this was increased 1.9-fold byRV1A. dsRNA induced CCL20 secretion more rapidly (2.9-fold increaseafter 16 hours incubation).CONCLUSIONS: RV1A and dsRNA are potent inducers of CCL20expression in hBECs. The biphasic pattern of induction suggests bothreceptor binding and replication processes may contribute to CCL20upregulation. CCL20 effects on mononuclear cell recruitment suggest apotential role in antiviral responses.Funding: NIH grants M01 RR03186, P01 HL70831, and P01 AI50500

CONCLUSIONS: Epithelial produced MIP-1� plays an important rolein animal model of asthma.Funding: Zhejiang provincial educational foundation,P.R. China

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