Abstract
Purpose :
To investigate the expression and function of Mannose Receptor (MR) and explore its interaction with Dectin-1 in human corneal epithelial cells (HCECs) exposed to Aspergillus fumigatus (A. fumigatus).
Methods :
HCECs were stimulated with A. fumigatus for 0,4, 8, 12, 16 and 24 hours. MR expression was tested by PCR, western-blot and immunohistochemistry. HCECs were pretreated with 2ug/ml MR blocking antibody and expression of p38, phosphorylated p38 (p-p38), the downstream cytokines (TNF-α, IL-1β) and Dectin-1 were tested by PCR, western-blot and ELISA. HCECs were pretreated with Dectin-1 agonists (curdlan, 100ug/ml) and inhibitors (laminarin, 10ug/ml) and expression of MR was tested.
Results :
MR expression was up-regulated after stimulated with A. fumigatus. MR mRNA and protein began to rise at 8 hours and 16 hours respectively. Stronger immunostaining of MR was observed in fungal infected corneal epithelium than in normal corneal epithelium. A. fumigates increased production of TNF-α (11-, 4-fold of control), IL-1β (4.7-, 3-fold of control), p-p38 (2.1-fold of control) and Dectin-1 (2.3-, 2-fold of control) in mRNA and protein levels. MR antibody significantly suppressed the expression of TNF-α (28%, 50% reduction), IL-1β (38%, 42% reduction), p-p38 (38% reduction) and Dectin-1 (48%, 47% reduction). Curdlan increased production of MR (1.5-, 1.9-fold of control) while laminarin decreased MR expression (50%, 60% reduction) induced by A. fumigatus.
Conclusions :
HCECs express MR and A. fumigates infection can increase MR expression. A. fumigates induce the expression of inflammatory cytokines via MR and p38 MAPK pathway. The expression of Dectin-1 and MR had mutual influence.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.