Abstract
Purpose :
To determine the role of autophagy in fungal keratitis caused by aspergillus fumigatus (A. fumigatus).
Methods :
The autophagy related proteins LC3B-II, Beclin-1, LAMP-1, and SQSTM1/p62 were tested by Western blotin normal and A. fumigatus-infected corneas of C57BL/6 mice. With the pretreatment of autophagy inhibitor 3-methyladenine (3-MA) or chloroquine (CQ), the expressions of autophagy related proteins were tested by Western blot. The fluorescence of LC3 and the infiltration of inflammatory cells were detected byimmunofluorescent staining. RT-PCR and Western blot were used to test the levels of HMGB1, IL-1β, IL-18, TNF-α, and IL-10. Disease severity was observed by slit lamp microscopy. Pathological changes of corneas were observed by H&E staining.
Results :
The expressions of autophagy related proteins LC3B-II, Beclin-1 and LAMP-1 were significantly elevated in mice corneas after fungal infection, and conversely, autophagic adaptor proteinSQSTM1/p62was down-regulated. Pretreatment with 3-MA or CQ aggravated the disease outcome and increased the infiltration of inflammatory cells and markedly elevated the expressions of HMGB1, IL-1β, IL-18 and TNF-α, but the expression of IL-10 in mice corneas was inhibited compared with the DMSO control in A. fumigatus-infected corneas. 3-MA significantly decreased the production of autophagy related proteins except p62, whereas CQ increased the expressions of LC3B-II, Beclin-1, LAMP-1 and p62 in corneas infected with A. fumigatus.
Conclusions :
These results demonstrate that A. fumigatusinfection increases the expression of autophagy in corneas and inhibition of autophagy aggravates the fungal keratitis caused by A. fumigatus.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.