Table 3.

Main mechanistic pathways related to biomarkers in IPF.

Mechanistic pathway	Biomarkers
Alveolar epithelial dysfunction	Alpha defensins, CA19-9, CA-125, CK18, KL-6/MUC1, MUC5B, PCSK6, osteopontin, SP-A, SP-C, SP-D, telomeres, telomerase
Immune dysregulation	Alpha defensins, CXCL13, CCL18, HSP70, microbiome, monocyte count, S100A12, TLR3, TOLLIP, Tregs, 52-gene signature
Extracellular matrix remodeling	Collagen degradation biomarkers, ECM neoepitopes, LOXL2, MMP7, PCSK6
Epigenetic markers	miR-29, let-7d, miR-21, miR-154, miR-302c, miR-423, miR-210, miR-376c, miR-185
Metabolism	Thyroid hormone, mitochondrial DNA

Abbreviations: ECM, extracellular matrix; KL-6, Krebs von den Lungen-6; MUC, mucin; SP, surfactant protein; TOLLIP, toll-interacting protein.