Charcot–Leyden Crystal Protein/Galectin-10 Is A Surrogate Biomarker of Eosinophilic Airway Inflammation in Asthma

Abstract

Aim: Eosinophilic asthma is associated with more exacerbations and differential responses to treatment. The aim of this study was to assess if CLC/Gal-10 and MBP-1 are surrogate biomarkers of eosinophilic inflammation in asthma. Methods & results: Sputum induction was performed in patients with asthma and in healthy controls. Sputum analysis revealed higher (p < 0.001) levels of CLC/Gal-10 and MBP-1 in asthmatics versus healthy controls. CLC/Gal-10 levels were highly correlated (r_s = 0.74; p < 0.001) with sputum eosinophils; MBP-1 approached significance (r = 0.44; p = 0.07). Conclusion: Increased CLC/Gal-10 and MBP-1 levels in the sputum were strongly correlated with sputum eosinophils in patients with asthma. CLC/Gal-10 and MBP-1 may be useful biomarkers for differentiation of eosinophilic airway inflammation in asthma.

Keywords:

• asthma
• biomarker
• eosinophil
• sputum

Acknowledgements

We would like to thank M Morales-Perez, K Watson and the UIC CCTS Clinical Research Center staff for their assistance in patient recruitment, enrollment and study visit completion. We would also like to acknowledge the patients that participated in this study.

Financial & competing interests disclosure

SJ Ackerman is a co-founder and member of the board of managers of EnteroTrack, LLC, the start-up company that is developing biomarker immunoassays (ELISAs) for clinical use with the esophageal string test. American Academy of Allergy, Asthma, & Immunology/Association of Specialty Professors T. Franklin Williams Scholar, University of Illinois at Chicago Center for Clinical and Translational Science (CCTS), award number KL2RR029878 from the National Center For Research Resources, Campaign Urging Research for Eosinophilic Diseases (SJ Ackerman), American Partnership for Eosinophilic Disorders (SJ Ackerman) and NIH/NHLBI Training Grant T32HL082547 (BT Maybruck). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center for Research Resources or the NIH. These funding agencies did not have any involvement in the study design; data collection, analysis and interpretation of data; writing the manuscript; or in the decision to submit the article for publication. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Ethical conduct of research

The research was carried out according to The Code of Ethics of the World Medical Association (Declaration of Helsinki), informed written consent was obtained from all participants, and the study was approved by the University of Illinois at Chicago Institutional Review Board.

Notes

^†Cohort 1.

^‡Cohort 2.

^§Methacholine challenge test was performed only if no evidence of reversibility (12% and 200 ml change in forced expiratory volume in 1 s (FEV₁)% predicted and FEV₁, respectively) was found in spirometry.

Additional information

Funding

SJ Ackerman is a co-founder and member of the board of managers of EnteroTrack, LLC, the start-up company that is developing biomarker immunoassays (ELISAs) for clinical use with the esophageal string test. American Academy of Allergy, Asthma, & Immunology/Association of Specialty Professors T. Franklin Williams Scholar, University of Illinois at Chicago Center for Clinical and Translational Science (CCTS), award number KL2RR029878 from the National Center For Research Resources, Campaign Urging Research for Eosinophilic Diseases (SJ Ackerman), American Partnership for Eosinophilic Disorders (SJ Ackerman) and NIH/NHLBI Training Grant T32HL082547 (BT Maybruck). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center for Research Resources or the NIH. These funding agencies did not have any involvement in the study design; data collection, analysis and interpretation of data; writing the manuscript; or in the decision to submit the article for publication. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.