BACKGROUND: Cytokines and chemokines have been implicated in the pathogenesis of asthma. Inhaled corticosteroids have been shown to decrease the number of eosinophils and to downregulate T H 2 cytokines but to increase neutrophils. The effect of corticosteroids on chemokine expression in asthma has not yet been investigated. OBJECTIVE: We sought to investigate the effect of a 2-week course of oral corticosteroid (methylprednisolone, 40 mg/d) on the expression of CXC chemokines (IL-8 and IFN-gamma-inducible protein 10 [IP-10]) and CC chemokines (eotaxin and monocyte chemotactic proteins [MCPs] 1-4) in endoscopic biopsy specimens of 13 patients with moderate-to-severe asthma. METHODS: CD3, major basic protein, and elastase immunoreactivities were monitored before and after treatment by using immunocytochemistry. Eotaxin, IL-8, IP-10, MCP-1, MCP-2, MCP-3, and MCP-4 mRNA expression in epithelium and submucosa were studied by using in situ hybridization. RESULTS: Corticosteroids reduced the number of CD3-positive T cells and major basic protein-positive eosinophils ( P < .05), whereas the number of neutrophils were increased ( P < .05). Corticosteroids also reduced the number of eotaxin ( P < .05), MCP-3, and MCP-4 mRNA-positive cells ( P < .001) in the epithelium and subepithelium. However, corticosteroids caused a significant increase in the epithelial expression of IL-8 ( P < .001), IP-10 ( P < .05), and MCP-2 mRNAs ( P < .01). Corticosteroids had no effects on MCP-1 mRNA expression. CONCLUSION: Our results demonstrate the dual nature of corticosteroids. Although corticosteroids can downregulate the expression of some asthma-associated chemokines, such as eotaxin, MCP-3, and MCP-4, they can also upregulate the expression of other chemokines, including IL-8, IP-10, and MCP-2. The failure of oral corticosteroids to inhibit IL-8 mRNA expression might contribute to persistent airway neutrophilia observed in patients with moderate-to-severe asthma, despite treatment with corticosteroids.
BACKGROUND: Cytokines and chemokines have been implicated in the pathogenesis of asthma. Inhaled corticosteroids have been shown to decrease the number of eosinophils and to downregulate T H 2 cytokines but to increase neutrophils. The effect of corticosteroids on chemokine expression in asthma has not yet been investigated. OBJECTIVE: We sought to investigate the effect of a 2-week course of oral corticosteroid (methylprednisolone, 40 mg/d) on the expression of CXC chemokines (IL-8 and IFN-gamma-inducible protein 10 [IP-10]) and CC chemokines (eotaxin and monocyte chemotactic proteins [MCPs] 1-4) in endoscopic biopsy specimens of 13 patients with moderate-to-severe asthma. METHODS: CD3, major basic protein, and elastase immunoreactivities were monitored before and after treatment by using immunocytochemistry. Eotaxin, IL-8, IP-10, MCP-1, MCP-2, MCP-3, and MCP-4 mRNA expression in epithelium and submucosa were studied by using in situ hybridization. RESULTS: Corticosteroids reduced the number of CD3-positive T cells and major basic protein-positive eosinophils ( P < .05), whereas the number of neutrophils were increased ( P < .05). Corticosteroids also reduced the number of eotaxin ( P < .05), MCP-3, and MCP-4 mRNA-positive cells ( P < .001) in the epithelium and subepithelium. However, corticosteroids caused a significant increase in the epithelial expression of IL-8 ( P < .001), IP-10 ( P < .05), and MCP-2 mRNAs ( P < .01). Corticosteroids had no effects on MCP-1 mRNA expression. CONCLUSION: Our results demonstrate the dual nature of corticosteroids. Although corticosteroids can downregulate the expression of some asthma-associated chemokines, such as eotaxin, MCP-3, and MCP-4, they can also upregulate the expression of other chemokines, including IL-8, IP-10, and MCP-2. The failure of oral corticosteroids to inhibit IL-8 mRNA expression might contribute to persistent airway neutrophilia observed in patients with moderate-to-severe asthma, despite treatment with corticosteroids.
Authors: Andrea C Valladao; Charles W Frevert; Lisa K Koch; Daniel J Campbell; Steven F Ziegler Journal: J Immunol Date: 2016-11-04 Impact factor: 5.422
Authors: Laura McKinley; John F Alcorn; Alanna Peterson; Rachel B Dupont; Shernaaz Kapadia; Alison Logar; Adam Henry; Charles G Irvin; Jon D Piganelli; Anuradha Ray; Jay K Kolls Journal: J Immunol Date: 2008-09-15 Impact factor: 5.422