BACKGROUND: Cockroaches are potent aeroallergens associated with asthma. Several reports suggest that a novel group of G protein-linked receptors, protease-activated receptors (PARs), may be involved in the intracellular signaling pathway induced by aeroallergens of the epithelial cells. OBJECTIVE: To investigate the mechanisms of American cockroach allergens (CraA) on interleukin 8 (IL-8) in human pulmonary epithelial cells. METHODS: Protease activities of CraA were quantified by the Azocoll method. The gene and protein expressions of IL-8 from CraA-stimulated A549 cells were quantified by real-time polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. The activity of different mitogen-activated protein kinases (MAPKs) was assessed by Western blot. RESULTS: CraA-induced A549 cell IL-8 secretion in a dose-dependent manner at both the messenger RNA and protein levels. CraA-induced IL-8 secretion can be blocked by serine protease inhibitors, phenylmethane sulfonyl fluoride, and aprotinin but not by other protease inhibitors. Blocking antibodies against the cleavage sites of PAR-2 and PAR-3, but not of PAR-1, inhibited CraA-induced IL-8 production. CraA induced significant PAR-2 and PAR-3 messenger RNA upregulation and extracellular-regulated kinase (ERK/1/2) and Jun N-terminal kinase (JNK) phosphorylation but not p38 MAPK. Furthermore, ERK1/2 (U0126) and JNK (SP600125) inhibitors inhibited CraA-induced IL-8 secretion by 100% and 45%, respectively. CONCLUSIONS: Both PAR-2 and PAR-3 might play a role in CraA-induced IL-8 secretion from human airway epithelial cells. It signals mainly through the ERK1/2 and partly from the JNK pathways. The key receptors and signaling molecules mediate cytokine release from the respiratory epithelium and can be potential therapeutic targets in treating cockroach allergy.
BACKGROUND: Cockroaches are potent aeroallergens associated with asthma. Several reports suggest that a novel group of G protein-linked receptors, protease-activated receptors (PARs), may be involved in the intracellular signaling pathway induced by aeroallergens of the epithelial cells. OBJECTIVE: To investigate the mechanisms of American cockroach allergens (CraA) on interleukin 8 (IL-8) in human pulmonary epithelial cells. METHODS: Protease activities of CraA were quantified by the Azocoll method. The gene and protein expressions of IL-8 from CraA-stimulated A549 cells were quantified by real-time polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. The activity of different mitogen-activated protein kinases (MAPKs) was assessed by Western blot. RESULTS:CraA-induced A549 cell IL-8 secretion in a dose-dependent manner at both the messenger RNA and protein levels. CraA-induced IL-8 secretion can be blocked by serine protease inhibitors, phenylmethane sulfonyl fluoride, and aprotinin but not by other protease inhibitors. Blocking antibodies against the cleavage sites of PAR-2 and PAR-3, but not of PAR-1, inhibited CraA-induced IL-8 production. CraA induced significant PAR-2 and PAR-3 messenger RNA upregulation and extracellular-regulated kinase (ERK/1/2) and Jun N-terminal kinase (JNK) phosphorylation but not p38 MAPK. Furthermore, ERK1/2 (U0126) and JNK (SP600125) inhibitors inhibited CraA-induced IL-8 secretion by 100% and 45%, respectively. CONCLUSIONS: Both PAR-2 and PAR-3 might play a role in CraA-induced IL-8 secretion from human airway epithelial cells. It signals mainly through the ERK1/2 and partly from the JNK pathways. The key receptors and signaling molecules mediate cytokine release from the respiratory epithelium and can be potential therapeutic targets in treating cockroach allergy.
Authors: Jay Portnoy; Ginger L Chew; Wanda Phipatanakul; P Brock Williams; Carl Grimes; Kevin Kennedy; Elizabeth C Matsui; J David Miller; David Bernstein; Joann Blessing-Moore; Linda Cox; David Khan; David Lang; Richard Nicklas; John Oppenheimer; Christopher Randolph; Diane Schuller; Sheldon Spector; Stephen A Tilles; Dana Wallace; James Seltzer; James Sublett Journal: J Allergy Clin Immunol Date: 2013-08-09 Impact factor: 10.793
Authors: James A Reihill; Xuan Ouyang; Zhixuan Yang; Lisa E J Douglas; Mei Zhou; Tianbao Chen; S Lorraine Martin Journal: Biomolecules Date: 2020-03-28