4. Current and future asthma biomarkers:
The National Institutes of Health (NIH, USA) defines a biomarker as “a characteristic that is objectively measured and evaluated as an indicator of normal biological processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention”. An ideal biomarker for asthma should have high sensitivity and specificity, can reflect intrinsic pathology, can be used to identify clinical phenotypes or treatment response phenotypes, and to assess changes in disease activity.
The above content suggests that since the bronchial epithelium plays a key role in the origin and development of asthma that proteins and genes derived from airway epithelium are likely to become biomarkers for asthma. The literature on asthma biomarkers includes many epithelial and epithelium- and tissue-associated biomarkers. In Table 1, we list the currently proposed candidate biomarkers as well as their potential sampling compartment, advantages, disadvantages and utility for clinical use.
Table 1. Candidate biomarkers and a summary of major biomarker characteristics. Potential biomarkers are described, and references are listed in the table. (Red represents studies in human specimens)