Int J Clin Exp Pathol 2016;9(9):8922-8932 www.ijcep.com /ISSN:1936-2625/IJCEP0036540

Original Article Potential biomarkers of idiopathic pulmonary fibrosis discovered in serum by proteomic array analysis

Rui Niu1, Xiaohui Li2, Yuan Zhang3, Hui Wang1, Yongbin Wang1, Ying Zhang1, Wei Wang1

Departments of 1Respiratory Medicine, 2Nursing, 3Evidence-Based Medicine, Second Hospital of Shandong University, Shandong, China Received July 24, 2016; Accepted July 25, 2016; Epub September 1, 2016; Published September 15, 2016

Abstract: Idiopathic pulmonary fibrosis (IPF) is a serious interstitial pneumonia leading to considerable morbidity and mortality. The unavailability of prompt biomarkers for IPF has hampered our ability to uncover preventive and therapeutic measures for this disease in a well-timed manner. The objective of this study was to identify valuable IPF associated blood biomarkers for stratifying patients and predicting outcome. By analyzing the expression of proteins in sera of 50 IPF patients and 10 healthy individuals using Biotin Label-based Array, we identified a signature of 46 differentially expressed proteins including 15 up-regulated and 31 down-regulated proteins as potential IPF biomarkers. The PPI network showed strong and complex interactions between identified biomarkers while functional enrichment analysis revealed their implications in 589 biological processes and 40 KEGG meta- bolic pathways. Western blotting and RT-PCR validation results corroborated with the data. Our research unearthed candidate biomarkers with great potential for diagnosis of IPF and suggested that recombinant throm- bopoietin and anti-CCL18 , as well as other identified biomarkers may represent a novel advance in the medical treatment of patients with IPF.

Keywords: Idiopathic pulmonary fibrosis, biomarkers, proteomic array

Introduction that are responsible for the development of specific diseases [4]. Compared to RNA-seq or Diverse responses and reactions that occur in microarray-based profiling of , the lung, including granulomatous disorders, which have been previously applied to IPF, pro- exposure to environmental dusts and toxins, teomics analysis offers various advantages [5, autoimmune diseases and drugs, generally 6]. In particular, proteomics indicates the effec- lead to pulmonary fibrosis. The most common tive existence of functional proteins in studied and severe form of pulmonary fibrosis is idio- samples. In addition, high transcriptional level pathic pulmonary fibrosis (IPF) which is charac- producing abundant quantity of mRNA does not terized by a progressive distortion of the alveo- imply the high amount of the corresponding pro- lar architecture and the replacement by fibrotic tein or its effectual activity [7]. Therefore, pro- tissues, resulting in a progressive dyspnea and teomics is significantly advantageous in facili- a loss of the respiratory function [1]. On aver- tating the discovery of specific diagnostic bio- age, half of patients with IPF decease within 3 markers and new therapeutic targets. Proteome years after diagnosis as a result of respiratory profiler antibody arrays are suitable for screen- or heart failure [2, 3]. The high incidence of IPF ing biomarkers involved in a specific disease has conducted to the search for biomarkers as because they allow high-throughput and rapid an essential asset for diagnosis and prognosis of IPF patients and, more importantly, for the detection of multiple proteins with low sample assessment of therapeutic interventions. requirement [8-10]. In laboratories and clinics, antibody arrays have been successfully applied Proteomics tools allow the large-scale study of to uncover biomarkers of a variety of diseases gene expression at the protein level, and there- such as cancers [11-13]. Nevertheless, to the by enables the identification of gene regulation best of our knowledge, up to date, the applica- IPF biomarkers tion of antibody arrays to the identification of Collection and storage of blood biological markers in sera of IPF patients has not been deeply assessed. From each fasting subjects, 5 mL of peripheral blood were collected into a BD Vacutainer tube In this study, we used a RayBio® Human Biotin- without anticoagulant using standardized phle- labeled Antibody Array I to concurrently identify botomy procedures. After centrifugation at and determine concentrations of 507 serum 10,000 rpm for 10 minutes at 4°C, all samples proteins in a cohort of IPF patients and healthy were rapidly aliquoted and stored at -80°C until individuals. The study allowed the discovery of analysis. Only samples obtained before treat- a panel of 46 serum proteins as IPF biomarkers ment of IPF patients were employed for pro- and indicated their promising application in teomic analysis. All serum samples from IPF personalized medicine for discriminating pati- patients and healthy individual groups were ents with IPF and healthy subjects. randomized, and the researcher was blinded to their characteristics. Materials and methods Protein expression profiling using antibody Study population chip technology

This study included 50 IPF patients recruited at We employed the RayBio® Human Biotin-la- Second Hospital (20 cases) and Qilu Hospital beled Antibody Array I (AAH-BLG-1, RayBiotech, (10 cases) of Shandong University, Shandong Norcross, GA, USA), constituted of 507 differ- Province Hospital (10 cases) and Qianfoshan ent human proteins, to determine proteins dif- Hospital of Shandong (10 cases). The diagnosis ferentially expressed between IPF patients and of IPF was based on published consensus control subjects. The first step consisted in the guidelines [14] and the “Guidelines for biotinylation of the primary amine of the pro- Diagnosis and Management of Idiopathic teins in serum samples. Thereafter, the glass Pulmonary Fibrosis” established by the Chinese chip arrays were blocked and 400 μl biotin- Medicine Association and determined on the labeled samples were added onto the glass basis of high-resolution computed tomography chip which was preprinted with capture anti- (HRCT) or surgical lung biopsy showing a bodies, and incubated at room temperature for definite usual interstitial pneumonia pattern. 2 h. Subsequently, the chips were washed to The most common symptoms at the onset of remove free components. Protein chips were the disease were irritating cough, shortness of subsequently incubated at room temperature breath, dyspnea, loss of endurance activities for 1 h with streptavidin-conjugated fluorescent TM and other symptoms of dyspnea. The anoma- dye, HiLytePlus 532 (Cy3 equivalent) that was lies of pulmonary function included restriction purchased from AnaSpec (Freemont, CA, USA). of ventilation function and impairment of lung After that, the excess of streptavidin was diffusion. The X film of the chest showed a retic- removed and the glass chip dried. Finally, the TM ular shadow in the surrounding lung area, which signals were scanned using a GenePix 4000B laser scanner (Axon Instruments, Sunnyvale, occurred mainly in the basal part of the lung. ® The main HRCT results showed double lung CA 94089, USA) coupled with GenePix bottom patch or mesh like changes, with vary- ProMicroarray Image Analysis Software which was used for image analysis. ing degrees of grinding glass-like shadow. The healthy controls (10 cases) were selected after Protein array data analysis a rigorous physical examination at the Physical Examination Center of Second Hospital of The data resulted from RayBio® Human Biotin- Shandong University. Written informed consent labeled Antibody Array I assay of serum sam- was obtained from all subjects according to the ples stemming from IPF patients and healthy declaration of Helsinki and the study was controls were normalized based on the positive approved by the institutional review board of control signal, consisting of biotin-labeled anti- Second Hospital and Qilu Hospital of Shandong bodies printed on each array, compared to a University, Shandong Province Hospital, and common reference array. Signals of adjacent Qianfoshan Hospital of Shandong prior to spots were measured as background signals. patients’ enrollment. After withdrawing background signals and nor-

8923 Int J Clin Exp Pathol 2016;9(9):8922-8932 IPF biomarkers

Table 1. Clinical and demographic IPF variables catego- Retrieval of Interacting Genes (STRING) rized by forced vital capacity (FVC, (%)) and diffusing database (http://string-db.org) to dis- close possible connections among pro- capacity for carbon monoxide (DLCO (%)) teins and visualize the PPI (protein-pro- Healthy Variable Characteristics IPF (N=50) control tein interaction) network. The PPI net- (N=10) work was constructed using the cut-off Predicted FVC (%) 80±10% 100% value of a confidence score >0.15. The GO and KEGG pathway enrichment anal- Predicted DLCO (%) 72±8% 100% yses of genes in the PPI network were Age (years) Mean ± SD 64.3±10.56 66.98±8.48 realized to pinpoint their biological func- Range 41-71 49-80 tions and pathways, based on the hyper- Sex Male 34 6 geometric distribution algorithm. P<0.05 Female 16 4 was chosen as the cut-off value for sig- Smoking status Current smokers 0 0 nificantly enriched functions and path- Former smokers 11 0 ways. Never smoked 30 0 Validation of the proteomic array data Not reported 9 0 Protein isolation and western blot analy- Table 2. Primers used in this study sis Gene name Primer Prior to western blotting analysis, total THPO F: 5’-ATGGAGCTGACTGAATTGCTCCTCG-3’ proteins were extracted from blood sam- R: 3’-CGAGGAGCAATTCAGTCAGCTCCAT-5’ ples. Equivalent quantities of extracts IL-17B F: 5’-ATGGACTGGCCTCACAACCTGCTGT-3’ (10 µg) were electrophoresed on 10% R: 3’-ACAGCAGGTTGTGAGGCCAGTCCAT-5’ SDS-PAGE gels followed by transfer to uPA F: 5’-ATGGTCTTCCATTTGAGAACTAGAT-3’ PVDF-Plus membranes (GE Osmonics, R: 3’-ATCTAGTTCTCAAATGGAAGACCAT-5’ Trevose, PA). Western blotting was achieved with primary antibodies pur- BIK F: 5’-ATGTCTGAAGTAAGACCCCTCTCCA-3’ chased form ABCAM including anti- R: 3’-TGGAGAGGGGTCTTACTTCAGACAT-5’ thrombopoietin antibody (ab115679), TNFRSF1B F: 5’-ATGGCGCCCGTCGCCGTCTGGGCCG-3’ anti-IL17B antibody (ab106272), Anti- R: 3’-CGGCCCAGACGGCGACGGGCGCCAT-5’ uPA antibody [U-16] (ab131433), anti- CCL25 F: 5’-ATGAACCTGTGGCTCCTGGCCTGCC-3’ Bik antibody (ab52182), anti-TNFRSF1B R: 3’-GGCAGGCCAGGAGCCACAGGTTCAT-5’ antibody (ab117543), anti-TECK anti- TGF-β3 F: 5’-ATGAAGATGCACTTGCAAAGGGCTC-3’ body [EPR12388(2)] (CCL25) (ab2003- R: 3’-GAGCCCTTTGCAAGTGCATCTTCAT-5’ 43) and anti-TGF-ß3 antibody (ab15537) CCL18 F: 5’-ATGAAGGGCCTTGCAGCTGCCCTCC-3’ and Anti-Macrophage Inflammatory Pro- R: 3’-GGAGGGCAGCTGCAAGGCCCTTCAT-5 tein 4 antibody (CCL18) [MM0142-7N58] (ab89338). Subsequently to the incuba- tion with secondary antibodies, specific malizing to positive controls, comparison of bands were visualized by using an improved final signal intensities among array images was chemiluminescence system (PerkinElmer Life used to determine relative difference in expres- Sciences, Boston, MA) according to the ven- sion levels of each protein between samples or dor’s guidelines while the shareware software, groups. The expression levels of proteins with ImageJ (http://rsbweb.nih.gov/ij/) was employ- fold increase ≥1.5-fold or fold decrease ≤0.65- ed for densitometry. GAPDH was used as fold in signal intensity were considered as mea- endogenous control. surable and presenting significant difference among patients and healthy subjects. RNA extraction and real time PCR

Construction of IFP regulatory network and Total RNA was extracted from blood samples functional enrichment analyses using the PAX gene Blood RNA kit (PreAnalytiX, 762164) according to the protocol provided The set of differentially expressed proteins was with the kit. After quantification of total RNA mapped by the online Search Tool for the by Nanodrop ND-1000 spectrophotometer (Na-

8924 Int J Clin Exp Pathol 2016;9(9):8922-8932 IPF biomarkers

Figure 1. Representative results for 507-marker antibody arrays. Spectrum of proteins was profiled using RayBio® Human Biotin-labeled Antibody Array I from serum of normal case (A) and IPF patient (B). noDrop Technologies, Wilmington, DE), the ferences between IPF patients and healthy quality of the RNA was evaluated using the controls. 2100 Bioanalyzer (Agilent, Palo Alto, CA). PCR was carried out using a 7900TH Fast Real-Time Results PCR model (Applied Biosystems, Foster City, Performance of biotin-labeled-based antibody CA, USA). PCR reactions were done in triplicate, arrays and the threshold cycle numbers were aver- aged. ACTB (actin, beta) was employed as an To discover biomarkers for IPF, serum samples endogenous control. Calculations of gene from 50 IPF patients and 10 healthy controls expression levels were performed using the were assayed for differential expression analy- 2-ΔΔCt method. PCR primers for THPO, IL-17B, sis using the antibody microarray constituted of uPA, BIK, TNFRSF1B, CCL25, TGF-β3 and 507 proteins. Serum samples were provided by β-actin were designed using the Primer Premier our colleagues and were collected from indi- software version 5 and are summarized in viduals of different age and sex (Table 1). After Table 2. purchased from Weitonglihu proce- random division into 3 groups, sera from IPF dure and the pulmonary fibrosis instillation patients or healthy controls within a group were phosphate-buffered eobnn perni-osuiiytem k mixed and respectively used to perform expres- histopathological examination fibrosis. sion analysis. Representative antibody microar- ray images of sera from IPF patients and Statistical analysis healthy controls are shown in Figure 1. The result demonstrated that active signal intensi- One-way ANOVA statistical analyses incorpo- ties, regular and different spot morphologies rated in GraphPad Prism 5 (GraphPad Softwa- and high signal to noise ratios were achieved. re, Inc., San Diego, CA, USA) was used to evalu- The signal intensity reflected the expression ate the significance of protein expression dif- level of specific proteins in each sample. The

8925 Int J Clin Exp Pathol 2016;9(9):8922-8932 IPF biomarkers

(TNFRSF11B, TNFRSF1B and XEDAR) between IPF patients and healthy controls were largely higher compared to other proteins. Proteins with high fold increase (3.53-4.93 folds) included XEDAR, TNF- RSF1B, CCL25, TGF-β3, VC- AM-1 and TNFRSF11B in this order. IL-17, SCF and IL-9 dis- played average fold increase values. In addition to up-regu- lated proteins, we equally identified 31 down-regulated proteins in the assay (Figure 2). Among these proteins, the expression of thrombopoietin was decreased about 12.5 fold compared to healthy sub- jects. The expression levels of the remaining proteins were decreased to almost the same extent.

Characteristic IPF regulatory Figure 2. Heatmap showing the expression profile of the differentially- ex pressed serum proteins. network based on identified proteins array data was normalized to the average of To further our understanding on the regulatory positive control signal intensity of each array. mechanisms of screened differentially expre- ssed proteins and find out their potential role in Protein expressions analysis and discovery of IPF, we assembled down-regulated and up-reg- biomarkers in serum of IPF patients ulated proteins for building a regulatory net- work using String software. The constructed The expression levels of all the proteins in regulatory network was depicted on Figure 3. healthy and IPF individuals were obtained after The result demonstrated that the screened dif- the antibody microarray analysis. After normal- ferentially expressed proteins form a complex ization and eliminating of proteins showing fold regulatory network characterized by protein- increase <2 and those with fold decrease >0.5, protein interactions. Strong protein-protein we obtained proteins presenting potential inter- interactions were symbolized by thick lines est as IPF biomarkers. Figure 2 depicts the while tiny line denoted low interactions (Figure heatmap of the expression profiles of these 3). As shown in Figure 3, four cores of robust proteins in IPF patients and healthy individuals. interactions were identified. The first one was After comparing the relative protein concentra- recorded among chemokines and was orches- tions among the two groups, we found that 15 trated by CCR1 and CCR7 while the second proteins were up-regulated in the serum of IPF one was governed by IL-17A, the third one by patients compared to that of healthy individu- TGF-β3 and the fourth one predominantly con- als. As shown in Figure 2, the 15 up-regulated trolled by CTNNB1. biomarkers included CXCL16, CCL18, CCL17, CCL25, TNFRSF11B, TNFRSF1B, XEDAR, CTGF/ GO functional enrichment analysis CCN2, Glucagon, IL-9, IL-17, SCF, TGF-β3 and VCAM-1 and ß-catenin. Among these proteins, GO enrichment analysis revealed that differen- chemokines and tumor necrosis factor recep- tially down- and up-regulated proteins were tor (TNFR) superfamily members were the most involved in 589 significant functional terms predominant. Interestingly enough, values of (p-value <0.05) in the category of “biological fold-change of TNFR superfamily members process”, 18 in the category of “molecular fun-

8926 Int J Clin Exp Pathol 2016;9(9):8922-8932 IPF biomarkers

Figure 3. IPF-specific regulatory network constructed using the differentially expressed serum proteins. ction” and 25 in the category of “cellular com- vity (7 proteins), receptor binding (2 proteins), ponent”. The functional terms in each category, C-C chemokine binding (2 proteins), Wnt- ranked by statistical significance, were summa- activated receptor activity (2 proteins), chemo- rized in Supplementary Table 1. As presented kine binding (2 proteins) and CCR chemokine in Figure 4, the top significantly enriched GO receptor binding (2 proteins) were the most terms in the category of “biological process” enriched terms. Extracellular space [15] and included positive regulation of multicellular extracellular region part [14] were the most sig- organismal process (14 proteins), inflammatory nificantly enriched terms in the category of “cel- response (10 proteins), positive regulation of lular components”. cytokine production (9 proteins), regulation of cytokine production (10 proteins), cell-cell sig- KEGG pathway enrichment analysis naling (12 proteins) and regulation of MAPK cascade (10 proteins). For “molecular function”, In order to identify metabolic pathways in which growth factor activity (7 proteins), cytokine acti- participate the differentially expressed pro-

8927 Int J Clin Exp Pathol 2016;9(9):8922-8932 IPF biomarkers

were mostly partners of cyto- kine-cytokine receptor inter- action and Chemokine signal- ing pathway.

Western blotting and real- time PCR validation

Western blotting and Real- Time PCR validation were per- formed to validate the anti- body microarray profiling re- sults using serum samples collected from IPF patients and healthy controls. All the proteins tested were validat- ed by Real-Time PCR and Western blotting validation as depicted in Figure 6 and pre- sented the same trends as in the microarray data.

Discussion

IPF is a progressive and irre- versible fibrosing lung disease with unknown etiology and unfavorable outcome, leading ultimately to death due to respiratory failure [1, 3]. Alth- ough the pathophysiology underlying this disease has not been fully elucidated, ani- Figure 4. GO enrichment analysis of genes of the IPF-specific regulatory network. mal models of pulmonary fibrosis have tremendously contributed in dissecting the teins, we proceeded to the KEGG enrichment molecular basis of this disease with a particu- analysis using the String database. The whole lar emphasis on cytokines as important patho- set of proteins involved in the regulatory net- genic mediators of lung fibrosis [15-17]. In this work was significantly (p-value <0.05) enriched study, the comparative analysis of expression for 40 metabolic pathways (Supplementary levels of proteins in sera of IPF patients and Table 2). The 21 most significant pathways healthy controls using antibody-based microar- were presented in Figure 5. The result showed rays allowed the identification of forty-six differ- that the cytokine-cytokine receptor entially expressed proteins. Remarkably, che- Interaction (19 proteins) was the topmost mokines and members of the TNFR superfamily enriched pathway. In addition, TGF-ß signaling were the most abundant in terms of number pathway (7 proteins), Wnt signaling pathway (8 and expression levels. This result was in accor- proteins), chemokine signaling pathway (8 pro- dance with previous findings which reported teins) and Hippo signaling pathway (7 proteins) the role of these molecules in the development were found as significant pathways following of fibrosis [18-20]. Chemokines constitute a cytokine-cytokine receptor interaction. Toll-like crucial group of cytokines that has the potential receptor signaling pathway, TNF signaling path- to regulate cell recruitment, the amplification way and Jak-STAT signaling pathway were also and polarization of the immune response and significantly enriched. Up-regulated proteins vascular remodeling [21, 22]. Chemokines, by

8928 Int J Clin Exp Pathol 2016;9(9):8922-8932 IPF biomarkers

BAL of IPF patients) was Figure 5. KEGG enrichment found up-regulated in this analysis of genes of the IPF- study and was consistent specific regulatory network. with the previous published studies [25-27]. CCL25 is ch- emotactic for lymphocytes, dendritic cells (DCs), and acti- vated macrophages [28]. It was found to contribute to liver fibrosis by directly target- ing HSCs in the injured liver and recruiting CCR9 positive macrophages [29]. In our arr- ay, the expression of CCL25 increased highly in IPF patient (fold change =4.228) indicat- ing its potential application in IPF diagnosis.

The beta-Catenin pathway is down-regulated in emphyse- ma but up-regulated in IPF, as confirmed by several studies [30, 31]. In the present study, ß-catenin was up-regulated in IPF and further confirmed its implication in the pathogene- sis of this disease.

As expected, numerous pro- teins involved in the extracel- lular space and extracellular region part were the most sig- nificantly represented in the mobilizing mononuclear cells which can impact category of “cellular components” as revealed on the epithelial-myofibroblast axis, play a key by GO functional enrichment, showing deregu- role in IPF pathogenesis. Therefore, the dis- lations of genes implicated in ECM. The physio- equilibrium of the expression of chemokines pathology of fibrosis remains an enigma, but seems to play important functions in fibroprolif- considerable researches have highlighted in- erative disorders in the lung. Recently, it has flammatory response as the key driver of unre- been reported that CXCL16 is induced in renal strained wound healing following fibrosis in tubular epithelial cells in response to angioten- numerous organ systems [32, 33]. The com- sin II and plays a pivotal role in the pathogene- mon paradigm hypothesizes that an initial alve- sis of angiotensin II-induced renal injury and olar injury causes an inflammatory response to fibrosis by controlling the intrusion of macro- subsequently cause fibrosis [34]. The GO phage and accumulation in bone marrow- enrichment of differentially expressed proteins derived fibroblast [23]. CCL17 has been found was in accordance with the above statement in the epithelium of both the bleomycin model since inflammatory response, positive regula- and human IPF lung tissues, suggesting that tion of cytokine production and regulation of CCL17 plays an important function in the epi- cytokine production were among the most rep- thelium during the pathogenesis of pulmonary resented proteins. fibrosis [24]. Similarly, CCL18, one of the most promising biomarkers for IPF (independent pre- Lung fibrosis is linked with abnormal expres- dictor of outcome, overexpressed in serum and sion of TGF-β receptors, increased activity of

8929 Int J Clin Exp Pathol 2016;9(9):8922-8932 IPF biomarkers

Figure 6. Western blotting and real-time PCR validation of screened biomarkers. (A) Electrophoregram, (B) Quantitative values of western blotting results, (C) Relative expres- sion of mRNA (A) and Masson (B), recombi- nant proteins antibodies 28IPF induction by bleomycin.

TGF-β-regulated proteins especially TGF-β1 sig- enrichment for cytokine-cytokine receptor naling pathway [35]. In this study, we found up- interaction and chemokine related activities. regulation of TGF-β3 and down-regulation of No strong interaction was recorded for the high- the type III TGF-β receptor (TGF-β RIII) showing ly increased XEDAR protein or the extremely the implication of TGF-β signaling pathway in decreased thrombopoietin suggesting that IPF. CTGF, a major profibrotic growth factor was these proteins might work independently or also found among the most downregulated pro- interact with other proteins that were not identi- teins in patients with IPF compared to fied in this study. The strong interactions controls. between some of differentially expressed pro- tein indicated their validity as useful molecular Although our antibody microarray detected biomarkers for IPF. This observation also sug- some of biomarkers previously reported in IPF, gests that IPF is a result of conjugated actions the data obtained here contains a substantial of genes or proteins working independently or number of unidentified biomarkers that could in complex interaction networks. potentially contribute in the diagnosis and treatment of IPF. For example, we found that The antibody microarray data was further vali- THPO was the most down-regulated protein dated using western blotting and RT-PCR. The while XEDAR was the most overexpressed. validation experimental results were in confor- These proteins have not been reported previ- mity with the antibody microarray. In summary, ously as IPF biomarkers. The regulatory net- in this study we identify proteomic signatures work constructed in the present study demon- that characterize IPF using the antibody micro- strated robust interactions between chemo- array. Protein-protein network and GO and kines. In addition, functional analyses revealed KEGG enrichment analyses identified several

8930 Int J Clin Exp Pathol 2016;9(9):8922-8932 IPF biomarkers biological processes and metabolic pathways, [7] Dhingra V, Gupta M, Andacht T, Fu ZF. New yielding new insight into mechanisms involved frontiers in proteomics research: a perspec- in fibrosis development. Among the 46 differen- tive. Int J Pharm 2005; 299: 1-18. tially expressed proteins discovered, the major- [8] RP H. An array of possibilities in cancer re- ity can prove interesting in the future as real search using cytokine antibody arrays. Expert Rev Proteomics 2007; 4: 299-308. diagnostic and prognostic biomarkers, but fur- [9] Abreu MT. Toll-like receptor signalling in the in- ther investigations are required for the evalua- testinal epithelium: how bacterial recognition tion and validation of their medical utility. shapes intestinal function. Nat Rev Immunol 2010; 10: 131-144. Acknowledgements [10] Sanchez-Carbayo M. Antibody arrays: techni- cal considerations and clinical applications in This work is supported by the Science and cancer. Clin Chem 2006; 52: 1651-1659. Technology Development Plan of Shandong [11] Jiang W, Huang R, Duan C, Fu L, Xi Y, Yang Y, Provinve (2014GSF118116) and the Autono- Yang WM, Yang D, Yang DH, Huang RP. mous Creative Fund of Shandong University Identification of five serum protein markers for (20122025). detection of ovarian cancer by antibody arrays. PLoS One 2013; 8: e76795. Disclosure of conflict of interest [12] Wang X, Yu J, Sreekumar A, Varambally S, Shen R, Giacherio D, Mehra R, Montie JE, Pienta KJ, None. Sanda MG, Kantoff PW, Rubin MA, Wei JT, Ghosh D, Chinnaiyan AM. Autoantibody signa- Address correspondence to: Wei Wang, Department tures in prostate cancer. N Engl J Med 2005; of Respiratory Medicine, Second Hospital of 353: 1224-1235. Shandong University, 247 Beiyuan Street, Shandong [13] Sanchez-Carbayo M, Socci ND, Lozano JJ, 250033, China. E-mail: [email protected] Haab BB and Cordon-Cardo C. Profiling blad- der cancer using targeted antibody arrays. Am References J Pathol 2006; 168: 93-103. [14] Raghu G, Collard HR, Egan JJ, Martinez FJ, [1] King TE Jr, Schwarz MI, Brown K, Tooze JA, Behr J, Brown KK, Colby TV, Cordier JF, Flaherty Colby TV, Waldron JA Jr, Flint A, Thurlbeck W, KR, Lasky JA, Lynch DA, Ryu JH, Swigris JJ, Cherniack RM. Idiopathic Pulmonary fibrosis: Wells AU, Ancochea J, Bouros D, Carvalho C, relationship between histopathologic features Costabel U, Ebina M, Hansell DM, Johkoh T, and mortality. Am J Respir Crit Care Med 2001; Kim DS, King TE Jr, Kondoh Y, Myers J, Müller 164: 1025-1032. NL, Nicholson AG, Richeldi L, Selman M, [2] Coultas DB, Zumwalt RE, Black WC and Dudden RF, Griss BS, Protzko SL, Schünemann Sobonya RE. The epidemiology of interstitial HJ; ATS/ERS/JRS/ALAT Committee on Idio- lung diseases. Am J Respir Crit Care Med pathic Pulmonary Fibrosis. An official ATS/ 1994; 150: 967-972. ERS/JRS/ALAT statement: idiopathic pulmo- [3] Perez A, Rogers RM and Dauber JH. The prog- nary fibrosis: evidence-based guidelines for di- nosis of idiopathic pulmonary fibrosis. Am J agnosis and management. Am J Respir Crit Respir Cell Mol Biol 2003; 29: S19. Care Med 2011; 183: 788-824. [4] Anderson NL and Anderson NG. Proteome and [15] Todd NW, Luzina IG and Atamas SP. Molecular proteomics: new technologies, new concepts, and cellular mechanisms of pulmonary fibro- and new words. Electrophoresis 1998; 19: sis. Fibrogenesis Tissue Repair 2012; 5: 11. 1853-1861. [16] Bergeron A, Soler P, Kambouchner M, Loiseau [5] Zuo F, Kaminski N, Eugui E, Allard J, Yakhini Z, P, Milleron B, Valeyre D, Hance AJ, Tazi A. Ben-Dor A, Lollini L, Morris D, Kim Y, DeLustro Cytokine profiles in idiopathic pulmonary fibro- B, Sheppard D, Pardo A, Selman M, Heller RA. sis suggest an important role for TGF-β and IL- Gene expression analysis reveals matrilysin as 10. Eur Respir J 2003; 22: 69-76. a key regulator of pulmonary fibrosis in mice [17] Coker RK and Laurent GJ. Pulmonary fibrosis: and humans. Proc Natl Acad Sci U S A 2002; cytokines in the balance. Eur Respir J 1998; 99: 6292-6297. 11: 1218-1221. [6] Selman M, Pardo A, Barrera L, Estrada A, [18] Borthwick LA, Wynn TA and Fisher AJ. Cytokine Watson SR, Wilson K, Aziz N, Kaminski N, mediated tissue fibrosis. Biochim Biophys Acta Zlotnik A. Gene expression profiles distinguish 2013; 1832: 1049-1060. idiopathic pulmonary fibrosis from hypersensi- [19] Sahin H and Wasmuth HE. Chemokines in tis- tivity pneumonitis. Am J Respir Crit Care Med sue fibrosis. Biochim Biophys Acta 2013; 2006; 173: 188-198. 1832: 1041-1048.

8931 Int J Clin Exp Pathol 2016;9(9):8922-8932 IPF biomarkers

[20] Oikonomou N, Harokopos V, Zalevsky J, [29] Chu PS, Nakamoto N, Ebinuma H, Usui S, Valavanis C, Kotanidou A, Szymkowski DE, Saeki K, Matsumoto A, Mikami Y, Sugiyama K, Kollias G, Aidinis V. Soluble TNF mediates the Tomita K, Kanai T, Saito H, Hibi T. C-C motif transition from pulmonary inflammation to fi- chemokine receptor 9 positive macrophages brosis. PLoS One 2006; 1: e108. activate hepatic stellate cells and promote liv- [21] Fernandez EJ and Lolis E. Structure, function, er fibrosis in mice. Hepatology 2013; 58: 337- and inhibition of chemokines. Annu Rev 350. Pharmacol Toxicol 2002; 42: 469-499. [30] Selman M and Pardo A. Stochastic Age-related [22] Le Y, Zhou Y, Iribarren P and Wang J. Chem- Epigenetic Drift in the Pathogenesis of Idio- okines and chemokine receptors: their mani- pathic Pulmonary Fibrosis. Am J Respir Crit fold roles in homeostasis and disease. Cell Mol Care Med 2014; 190: 1328-1330. Immunol 2004; 1: 95-104. [31] Song P, Zheng JX, Xu J, Liu JZ, Wu LY and Liu C. [23] Xia Y, Entman ML and Wang Y. Critical role of β-catenin induces A549 alveolar epithelial cell CXCL16 in hypertensive kidney injury and fibro- mesenchymal transition during pulmonary fi- sis. Hypertension 2013; 62: 1129-1137. brosis. Mol Med Rep 2015; 11: 2703-2710. [24] Belperio JA, Dy M, Murray L, Burdick MD, Xue [32] Satish L and Kathju S. Cellular and Molecular YY, Strieter RM, Keane MP. The Role of the Th2 Characteristics of Scarless versus Fibrotic CC Chemokine Lig and CCL17 in Pulmonary Wound Healing. Dermatol Res Pract 2010; Fibrosis. J Immunol 2004; 173: 4692-4698. 2010: 790234. [25] Prasse A, Pechkovsky DV, Toews GB, Jungrai- [33] Pellicoro A, Ramachandran P, Iredale JP and thmayr W, Kollert F, Goldmann T, Vollmer E, Fallowfield JA. Liver fibrosis and repair: im- Müller-Quernheim J, Zissel G. A vicious circle of mune regulation of wound healing in a solid alveolar macrophages and fibroblasts perpetu- organ. Nat Rev Immunol 2014; 14: 181-194. ates pulmonary fibrosis via CCL18. Am J Respir [34] Walters DM and Kleeberger SR. Mouse mo- Crit Care Med 2006; 173: 781-792. dels of bleomycin-induced pulmonary fibrosis. [26] Prasse A, Pechkovsky DV, Toews GB, Schäfer In: Curr Protoc Pharmacol 2008. M, Eggeling S, Ludwig C, Germann M, Kollert F, [35] Cabrera S, Selman M, Lonzano-Bolaños A, Zissel G, Müller-Quernheim J. CCL18 as an in- Konishi K, Richards TJ, Kaminski N, Pardo A. dicator of pulmonary fibrotic activity in idio- Gene expression profiles reveal molecular pathic interstitial pneumonias and systemic mechanisms involved in the progression and sclerosis. Arthritis Rheum 2007; 56: 1685- resolution of bleomycin-induced lung fibrosis. 1693. Am J Physiol Lung Cell Mol Physiol 2013; 304: [27] Prasse A, Probst C, Bargagli E, Zissel G, Toews L593-L601. GB, Flaherty KR, Olschewski M, Rottoli P, Müller-Quernheim J. Serum CC-chemokine li- gand 18 concentration predicts outcome in idiopathic pulmonary fibrosis. Am J Respir Crit Care Med 2009; 179: 717-723. [28] Vicari AP FD, Hedrick JA, Foster JS, Singh KP, Menon S, Copeland NG, Gilbert DJ, Jenkins NA, Bacon KB, Zlotnik A. TECK: a novel CC chemo- kine specifically expressed by thymic dendritic cells and potentially involved in T cell develop- ment. Immunity 1997; 7: 291-301.

8932 Int J Clin Exp Pathol 2016;9(9):8922-8932