Airway epithelial cells increase macrophage chemotaxis and inflammatory cytokine secretion under hypoxic conditions.
10.11817/j.issn.1672-7347.2019.02.004
- Author:
Xingwu CHEN
1
;
Lilong QING
2
;
Zhengui SUN
2
;
Min XING
2
;
Leilei ZANG
2
;
Hanli WANG
2
Author Information
1. Department of Respiratory, First Affiliated Hospital, Wannan Medical College, Wuhu Anhui 241001, China cxw0028@126.com.
2. Department of Respiratory, First Affiliated Hospital, Wannan Medical College, Wuhu Anhui 241001, China.
- Publication Type:Journal Article
- MeSH:
Cell Hypoxia;
Chemotaxis;
Cytokines;
Epithelial Cells;
Humans;
Hypoxia-Inducible Factor 1, alpha Subunit;
Macrophages
- From:
Journal of Central South University(Medical Sciences)
2019;44(2):134-143
- CountryChina
- Language:Chinese
-
Abstract:
To investigate the effects of airway epithelial cells on macrophages chemotaxis and inflammatory cytokine expression under hypoxic conditions.
Methods: Human bronchial epithelial cells (HBE) treated with different concentrations (0, 100, 200, 400, 800 μmol/L) of CoCl2 or transfected with HIF-1α siRNA were co-cultured with THP-1-derived M1 macrophages or M2 macrophages. The chemotactic effects on macrophages were analyzed by Transwell assay. The levels of TNF-α, IFN-γ, IL-4, IL-13 and IL-10 in the supernatants of macrophages were detected by ELISA, and HIF-1α or Cav-1 mRNA expression in HBE or macrophages was detected by RT-qPCR.
Results: HBE cells promoted macrophages chemotaxis in a time- and concentration-dependent manner. Compared to un-transfected group, the chemotactic ability of HBE transfected with HIF-1α siRNA was significantly weakened (P<0.01). Under the same culture conditions, the chemotaxis of M2 macrophages was greater than that in THP1-derived M1 macrophages. The concentrations of TNF-α, IFN-γ, IL-4, IL-13 and IL-10 in the supernatants of macrophages were increased in a time-and concentration-dependent manner. The concentrations of TNF-α and IFN-γ were increased further after co-culturing for 8 and 12 h; while IL-4, IL-13 and IL-10 concentrations were increased further during 24 h of co-culture. The levels of cytokines in the supernatants of macrophages co-cultured with HBE and transfected with HIF-1α siRNA were significantly lower than those in un-transfected cells (P<0.05 or P<0.01). The reduction of TNF-α or IFN-γ was more obvious. The expression of HIF-1α or Cav-1 mRNA in HBE or macrophages was increased in a concentration-dependent manner after 8 or 12 h co-culture, which was significantly reduced when HBE was transfected with HIF-1α siRNA.
Conclusion: Airway epithelial cells can enhance macrophages chemotaxis and pro-inflammatory cytokines expressions under hypoxic condition. HIF-1α and Cav-1 may be the important mediators in these processes.
