Potential biomarkers for diagnosis and disease evaluation of idiopathic pulmonary fibrosis

Abstract

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease characterized by progressive lung fibrogenesis and histological features of usual interstitial pneumonia. IPF has a poor prognosis and presents a spectrum of disease courses ranging from slow evolving disease to rapid deterioration; thus, a differential diagnosis remains challenging. Several biomarkers have been identified to achieve a differential diagnosis; however, comprehensive reviews are lacking. This review summarizes over 100 biomarkers which can be divided into six categories according to their functions: differentially expressed biomarkers in the IPF compared to healthy controls; biomarkers distinguishing IPF from other types of interstitial lung disease; biomarkers differentiating acute exacerbation of IPF from stable disease; biomarkers predicting disease progression; biomarkers related to disease severity; and biomarkers related to treatment. Specimen used for the diagnosis of IPF included serum, bronchoalveolar lavage fluid, lung tissue, and sputum. IPF-specific biomarkers are of great clinical value for the differential diagnosis of IPF. Currently, the physiological measurements used to evaluate the occurrence of acute exacerbation, disease progression, and disease severity have limitations. Combining physiological measurements with biomarkers may increase the accuracy and sensitivity of diagnosis and disease evaluation of IPF. Most biomarkers described in this review are not routinely used in clinical practice. Future large-scale multicenter studies are required to design and validate suitable biomarker panels that have diagnostic utility for IPF.

The roles of Th cells in myocardial infarction

“…Inhibition of cytokines such as TGF-β, IL-4, and IL-13 restricts fibroblast activation and collagen synthesis, thereby reducing fibrosis after myocardial infarction [ 56 ]. The concomitant production of IP-10 also has an antifibrotic effect [ 58 ]. Naive T cells Th2 CD3,CD4,CD119,CD193(CCR3),CD194(CCR4),CD365(Tim-1)… Promotes myocardial tissue repair by modulating macrophage phenotype, inhibiting inflammatory cells and thereby suppressing excessive inflammatory response, and increasing proliferation of repair-related cells [ 79 , 80 ].…”

“…Inhibition of cytokines such as TGF-β, IL-4, and IL-13 restricts fibroblast activation and collagen synthesis, thereby reducing fibrosis after myocardial infarction [ 56 ]. The concomitant production of IP-10 also has an antifibrotic effect [ 58 ].…”

“…Meanwhile, IFN-γ decreases secretion of interleukin-4 (IL-4) and interleukin-13 (IL-13) to inhibit Th2-mediated fibroblast activation and indirectly regulates fibrosis by impacting macrophage activation [ 56 ]; Furthermore, Th1 cells produce an additional antifibrotic agent called IP-10 (also known as CXCL10), which is found to elevate within 24 h of a MI [ 57 ]. The antifibrotic effect of CXCL10 is believed to result from the inhibition of fibroblast migration induced by basic fibroblast growth factor (BFGF) and the enhancement of growth factor-mediated wound contraction in collagen lattices filled with fibroblasts [ 58 ]. Overall, the presence of Th1 cells following a myocardial infarction restricts fibrosis by impeding fibroblast activation through direct and indirect means.…”

Unraveling the enigma: The emerging significance of pulmonary surfactant proteins in predicting, diagnosing, and managing COVID‐19

“…Yet, validating SP‐A's role in IPF diagnosis, prognosis, and treatment response requires further large‐scale studies. 34 , 35 SP‐A has the potential to be utilized as a biomarker for prognosticating the prognosis of chronic obstructive pulmonary disease (COPD). Diminished levels of SP‐A, which are associated with compromised immunity, could heighten the vulnerability to exacerbations of COPD.…”

“…Higher SP‐A levels are associated with increased mortality risk in IPF patients, hinting at its prognostic potential. Yet, validating SP‐A's role in IPF diagnosis, prognosis, and treatment response requires further large‐scale studies 34,35 . SP‐A has the potential to be utilized as a biomarker for prognosticating the prognosis of chronic obstructive pulmonary disease (COPD).…”