J ALLERGY CLIN IMMUNOL A b s t r a c t s $345 VOLUME 109, NUMBER 1

1 f ~ " ~ N Respiratory Syncytial Virus Infection and Asthma Link: Role l lJP/1~ of Dendritic Cells

Szilvia Barbara Nagy*, Timothy S Randall§, Richard F Lockey§, Shyam S Mohapatra* *University of South Florida and James A Haley Veterans Administration Hospital, Tampa, FL §University of South Florida, Tampa, FL

Recurrent respiratory syncytial virus (RSV) infection in allergen-sensi- tized mice results in augmentation of an allergic immune response, airway inflammation, and airway hyperresponsiveness (Matsuse et al. J Immunol 164:6853, 2000). However, the cellular and molecular basis for the shift from a virus-induced Thl-like to Th2-1ike response is poorly understood. The purpose of this study is to determine whether dendritic cells (DC) play a role in this process by investigating the distribution and migration of DC in ovalbumin-sensitized and/or RSV-infected mice. Groups of Balb/c mice were immunized and sensitized with ovalbumin and/or infected with puri- fied RSV, along with appropriate controls. Immunohistochemical staining for CD1 lc, specific for DC in mice, was performed on selected animals on days 1-4 after infection to follow the DC migration from the airways into the regional lymph nodes. Airway hyperresponsiveness was tested on selected mice on day four. The airway and lung sections of RSV-infected mice shows a statistically significant increase in number of DC compared to uninfected control mice. In contrast, such a difference is not found in sec- tions of the regional lymph nodes. DCs migrate into the regional lymph node from the airways on day 2 after infection. Fewer DCs are detected in either the airways or the lymph nodes after day three, and the number of DCs is the same as in infected and uninfected mice in both lymph nodes and lungs after the fourth day of infection. Although RSV replication can be seen in the lung tissue one day after infection, extensive lung inflammation, with bronchial exudates composed of mononuclear cells and eosinophils, and a marked tissue eosinophilic infiltration is found in these mice on day four. The airways of the allergen immunized and RSV infected mice show a significant increase in methacholine responsiveness at day four after infec- tion compared with all other groups. These results show that one-day after an RSV infection, sufficient RSV antigen is produced in the lung to trigger accumulation of DCs in the airway, which then migrate to lymph nodes. The pathological changes seen on day four are mainly related to the aller- gen- and virus-induced immune response, presumably via the release of different cytokines. Funding: The Joy McCann Culverhouse Endowment to the University of South Florida Airway Disease Center.

1071 NMR Analysis and Classification in Pulmonary Pathology

Sorin Musat-Marcu, Erik Saude, John Bagu, Brian Sykes, Melody Proda- niuk, Paige Lacy, Don Sin, Paul Man, Redwan Moqbel University of Alberta, Edmonton, Canada

BACKGROUND: Asthma and cystic fibrosis are characterized by dis- tinct patterns of airway inflammation. 1H-NMR is a highly specific tech- nique for the analysis of biometabolites.

OBJECTIVES: To employ NMR for the identification of biochemical and pathophysiological patterns in neutrophilic and eosinophilic airway inflammation.

METHODS: Six cystic fibrosis patients (CF) and six allergic asthma patients (AA) were selected based on the presence of neutrophil- and eosinophil-rich airway inflammation, respectively. Hypertonic saline- induced sputum samples were analyzed in a blinded fashion. A number of cytospins from mucus plugs, lysed with 0.1% DTT, were used for differen- tial cellular counts. For NMR analysis, we lysed 90 mg of mucus plugs by sonication, supplemented with 1 mM sodium 2,2-dimethyl-2-silapentane- 5-sulfonate (referenced at 0 ppm), 10 mM imidazole-4 D and 2.5 mM sodi- um azide. 1H NMR spectral analysis was performed on Varian 500 and 800 MHz spectrometers. The resulting spectra were analyzed for chemical shift and spin coupling patterns within the available NMR databases and con- firmed by spiking with pure standards, where applicable.

RESULTS: Distinct pattems of oxidative metabolism byproducts were found in CF and AA. We detected tyrosine halogenation by bromide (3- bromo- and 3,5-dibromotyrosine) in AA compared with chloride in CF (3- chloro- and 3,5-dichlorotyrosine). The ratio of free brominated versus chlori- nated tyrosine residues was 1.94---*-0.3 in AA compared with 0.65_+0.21 in CF patients (p--0.015). These findings showed clear correlations with differential cell counts, i.e. eosinophil- vs. neutrophil-rich sputum, respectively. This con- firmed our and others previous in vitro observations. Significant differences were detected in the concentration of tauline and lactic acid (elevated in CF: 812+_23 ~ and 2.113-+0.42mM vs. 279_+60 I.tM and 0.592_+0.12 mM in AA, p values of 0.050 and 0.004 respectively) whereas histidine was prominent in the AA samples (150-+301.tM vs. 61-+101.tM, p=0.036). In addition, three as yet unidentified compounds, (designated by their resonance frequencies: 3.60, 3.78 and 3.80 ppm) discriminated unequivocally between AA and CF: with "3.80" showing greater prominence in AA (893+_180l.tM vs. 378_+70~tM, p--0.021), "3.60" greater abundance in CF (890+160ktM vs. 394+_70 p.M, p--O.013) and "3.78" specificity for CF (618+_ 130 }.tM) but absent in AA.

CONCLUSION: NMR provides quantifiable and reproducible profiles to distinguish the inflammatory processes in cystic fibrosis and allergic asthma.

l Chronic Cough. Masquerading as a Fixed Obstruction. Alle- IIJP/~--- viated With Baclofen

Jonathan William Buttram, Larry Hagan Wilford Hall Medical Center, San Antonio, TX

CASE HISTORY: A 31 year old female with a 2 year history of cough was referred for evaluation of asthma. She experienced daily coughing paroxysms and complained of a constant "tickle" in her throat as well as throat tightness during coughing episodes. She had been treated with multi- ple asthma medications for one year without improvement. Over the past 6 months, her symptoms worsened such that she was using albuterol MDI every 4 hours without relief and waking 4 to 5 nights per week with cough. Peak flows had been stable without variability and did not improve after albuterol. 2 weeks of oral steroids did not relieve her symptoms. Review of systems was negative for rhinitis or gastroesophageal reflux. Her medical and family histories were negative for asthma or allergy. The patient was a non-smoker. Current medicines included: Flovent TM 220 mcg 2p bid, Serevent TM 2p bid, Albuterol TM 2-4p q4 prn, Singulair TM, Flonase TM, Clar- itin TM, and Prilosec TM. Physical exam: Ear, nose, throat, lung, and heart exams were unremarkable. PFT: FVC - 3.05 (89%), FEV1 - 2.66 (92%), FEV1/FVC - 87% Inspiratory and expiratory flow loops blunted. Prick skin tests: negative to aeroallergens. Procedures: CT of the neck and chest was normal. Remarkably, the patient's cough desisted after topical anesthe- sia (4% lidocaine) was applied for rhinoscopy. Rhinolaryngoscopy was normal. Pulmonary function testing (with topical anesthesia) revealed nor- mal flow loops. Histamine challenge was negative. Treatment: Current medications were discontinued, and the patient was given Tilade MDI and a 3 day course of Codiene for chronic cough. Cough resolved 36 hours after starting treatment but returned 24 hours after discontinuation of narcotics. Tilade provided no significant improvement. Given the inability to contin- ue chronic narcotic therapy, the patient was treated with Baclofen 5rag po bid for 2 weeks. Cough resolved within 1 week. Baclofen was then tapered over 2 weeks. The patient has not had recurrence of her cough.

DISCUSSION: Baclofen, a GABA-agonist, inhibits the cough reflex via central mechanisms in animals and has been used successfully at low dose to inhibit capsaicin-induced cough ] as well as ACE-inhibitor induced cough. 2 However, it is not widely studied or used. In this patient, Baclofen not only alleviated her cough but also resulted in the discontinuation of unneeded medications and avoidance of their possible side effects. Thus, the use of Baclofen should be considered in refractory cases of chronic cough and warrants further human study. 1 Dicpinigatis E Antitussive effect of the GABA-agonist baclofen. Chest 1997; 111:996-99 2 Dicpini- gatis E Use of baclofen to suppress cough induced by angiotensin-convert- ing enzyme inhibitors. Ann Pharmacother 1996 Nov;30(11): 1242-45.