Biomarkers of immune dysfunction in ILDs include cytokines or chemokines like IL-8, C-C motif ligand-2 (CCL2), CC chemokine ligand 18 (CCL18), CXC motif chemokine ligand 1 (CXCL1), C-X-C motif chemokine ligand 10 (CXCL10), C-X-C motif chemokine ligand 12 (CXCL12), C-X-C motif chemokine 13 (CXCL13), TNF-α, and others involved in innate and acquired immunity. The gene discussed is CXCL13; the disease is immune system disorder.