TABLE 3

Differentially expressed key proteins in sputum SomaLogic analysis comparing severe asthma ex-smokers (ESA) and healthy nonsmokers (NH) with severe asthma nonsmokers (NSA) and NH

Probe IDProtein targetGene symbolGene nameFunction
ESA-NH    
 SL004589AZU1AZU1Azurocidin 1A pre-proprotein of a mature azurophil granule antibiotic protein with monocyte chemotactic and antimicrobial activity
 SL000401ELANEELANENeutrophil elastaseThis protease hydrolyses proteins within specialised neutrophil lysosomes, called azurophil granules, as well as proteins of the extracellular matrix
 SL003192CFPCFPComplement factor properdinA positive regulator of the alternative pathway of complement system
 SL000039IL-8CXCL8 (=IL-8)C-X-C motif chemokine ligand 8Acts as one of the major mediators of the inflammatory response by recruiting neutrophils
NSA-NH    
 SL003524Protein disulfide isomerase A3PDIA3Protein disulfide isomerase family A member 3Formation of the final antigen conformation, export from the endoplasmic reticulum to the cell surface and adaptation to oxidative damage
 SL006108CD5LCD5LCD5 molecule likeThis secreted protein is mainly expressed by macrophages in lymphoid and inflamed tissues and regulates mechanisms in inflammatory responses. Regulation of intracellular lipids mediated by this protein has a direct effect on transcription regulation mediated by nuclear receptors ROR-γ (RORC)
 SL004068GZMBGZMBGranzyme BTargets cell lysis in cell-mediated immune responses. This protein also processes cytokines and degrades extracellular matrix proteins, and these roles are implicated in chronic inflammation and wound healing
ESA-NH and NSA-NH
 SL017613FCG2A/BFCGR2AFc fragment of immunoglobulin-γ receptor IIaCell surface receptor found on phagocytic cells such as macrophages and neutrophils, is involved in the process of phagocytosis and clearing of immune complexes
 SL000342CatalaseCATCatalaseA key antioxidant enzyme in the body's defence against oxidative stress
 SL000051CRPCRPC-reactive proteinHost defence based on its ability to recognise foreign pathogens and damaged cells of the host and to initiate their elimination by interacting with humoral and cellular effector systems in the blood
 SL004153M-CSF RCSF1RColony-stimulating factor 1 receptorThe receptor for CSF1, a cytokine which controls the production, differentiation and function of macrophages
 SL004853B7-H2ICOSLGInducible T-cell costimulatory ligandThis protein acts as a costimulatory signal for T-cell proliferation and cytokine secretion and induces B-cell proliferation and differentiation into plasma cells

Assay performed by SomaLogic (Boulder, CO, USA). IL: interleukin.