1181 URINARY PROTEOMIC ANALYSIS TO IDENTIFY HOST RESPONSE PROTEINS IN CATHETER-ASSOCIATED URINARY TRACT INFECTION

Abstract

You have accessJournal of UrologyInfections/Inflammation of the Genitourinary Tract: Kidney & Bladder1 Apr 20111181 URINARY PROTEOMIC ANALYSIS TO IDENTIFY HOST RESPONSE PROTEINS IN CATHETER-ASSOCIATED URINARY TRACT INFECTION Kathleen Mach, Xuefeng Ling, and Joseph Liao Kathleen MachKathleen Mach Stanford, CA More articles by this author , Xuefeng LingXuefeng Ling Stanford, CA More articles by this author , and Joseph LiaoJoseph Liao Stanford, CA More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.793AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Catheter-associated UTI (CAUTI) is the most common healthcare associated infection. Diagnosis of CAUTI is challenging as symptoms are frequently nonspecific and differentiation from asymptomatic bacteriuria (ASB) may be difficult. Hence, a better understanding of the host response to infection, ASB, or simply catheter presence will provide insight to direct clinical management. METHODS To identify proteins differentially expressed, we used two proteomic approaches, mass spectrometry (MS) and electrochemiluminescence arrays (ECL). Urine was collected with IRB approval from catheter-dependent patients and stored at -80°C until analysis. For MS (Thermo Velos Orbitrap), we analyzed 25 bacteria (+) and 25 bacteria (−) samples. MS output was searched against a database of human and bacterial proteomes with Sequest software. Spectral counting was used to determine relative quantitation, and data was visualized with Scaffold software. ECL analysis used a Meso Scale Discovery kit with a panel of 4 cytokines, IL-1β, IL-8, IL-6, and TNFα. For ECL, 6 bacteria (−) samples and 20 bacteria (+) samples divided into 11 ASB and 9 CAUTI, as determined by clinical diagnosis at the time of collection, were assayed. RESULTS Analysis of MS data identified greater than 1000 host and bacterial proteins. The top differentially expressed host proteins in each sample group are listed in the table. As MS provides relative data, we are currently verifying and quantitating these proteins in healthy, ASB and CAUTI urine. In the analysis of urinary cytokines (Figure), we note differences in the mean IL-1β and IL-8 level between the bacteria (−) and (+) samples, and a trend in differences in ASB and CAUTI samples. Host Proteins function Higher in bacteria (positive) Matrix metalloproteinase-9 (MMP9) Breakdown of extracellular matrix Plastin-2 (LCP1) Actin-binding protein Myeloperoxidase (MPO) Lysosomal protein, microbicidal activity of neutrophils Protein S100-A9 (S100A9) Proinflammatory protein, expressed in neutrophils and monocytes Lipocalin-2 (LCN2) Iron sequestration, binds to bacterial siderophores Neutrophil collagenase (MMP8) Breakdown of extracellular matrix Lactoferrin (LTF) Iron homeostasis, anti-microbial infections, anti-inflammatory activity Higher in bacteria (negative) Plasma serine protease inhibitor (SerpinA5) Heparin-binding serine protease inhibitor with broad antimicrobial activity Osteopontin (OPN) Secreted, integrin-binding protein, functions in the regulation of immune responses. Vasorin (VASN) TGFβ binding protein CONCLUSIONS Our data support the utility and complementary nature of the two technologies: MS scans the entire proteome, while ECL arrays detect known targets with a superior detection limit and quantitation. Additional investigation in a larger patient cohort is warranted and is underway. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e474 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Kathleen Mach Stanford, CA More articles by this author Xuefeng Ling Stanford, CA More articles by this author Joseph Liao Stanford, CA More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...