Periostin acts both as an
extracellular matrix protein belonging to the fasciclin family and as a matricellular
protein functioning in cell activation by binding to its receptors on the cell surface. It has been established that
periostin is a downstream molecule of
interleukin (IL)-13, a signature type 2
cytokine, and that
periostin plays an important role in the pathogenesis of allergic diseases, including
asthma. Based on these findings, much attention has been paid to
periostin as a
biomarker useful in the treatment of
asthma.
Periostin is a surrogate
biomarker for type 2 immunity; it has been shown that serum
periostin can predict the efficacy of anti-IL-13
antibodies (
lebrikizumab) and
anti-IgE antibodies (
omalizumab), and that this usefulness can be potentially expanded to other type 2 antagonists. Moreover, it has been shown that
periostin is not a simple surrogate
biomarker for type 2 immunity;
periostin-high
asthma patients have several unique characteristics, including
eosinophilia, high fraction of
nitric oxide,
aspirin intolerance,
nasal disorders, and late onset. These characteristics are likely to be correlated with the involvement of
periostin in the tissue remodeling of
asthma.
Periostin is also associated with hyporesponsiveness to inhaled
corticosteroids, probably reflecting tissue remodeling. Thus,
periostin has 2 characteristics as a
biomarker for early diagnosis of
asthma: surrogate
biomarkers for type 2 immunity and tissue remodeling. Based on these characteristics, we will be able to apply serum
periostin to treatment of
asthma.