LGALS3 and pulmonary fibrosis: In a US cohort of 121 IgG4-RD patients, using immunoaffinity chromatography and mass spectrometry of plasmablast clones, 34 (28%) were positive for IgG4-specific anti-galectin-3 antibody while almost none of the 45 disease controls with interstitial pulmonary fibrosis and 50 healthy volunteers showed similar results (121).