Abstract
Purpose :
To determine whether lectin-like ox-LDL receptor (LOX-1) regulates neutrophil apoptosis in A. fumigatus keratitis.
Methods :
The mRNA levels of Fas, Fas ligand (FasL), caspase-3(CASP3), caspase-8(CASP8), caspase-9(CASP9), and BCL2 was tested in normal and infected cornea of C57BL/6 mice fungal keratitis corneas. Treated with LOX-1 neutralizing antibody or LOX-1 inhibitor PolyI, Real-Time RT-PCR, TUNEL staining were used to test corneas infected with A. fumigatus. Immunofluorescence assays were used to test neutrophils infiltration of C57BL/6 mice corneas. Neutrophils were extracted from C57BL/6 mice, and pretreated with LOX-1 neutralizing antibody or IgG; LOX-1 inhibitor PolyI or PBS, then stimulated with A. fumigatus. The mRNA levels of Fas, FasL, CASP3, CASP8, CASP9, and BCL2 were evaluated by Real-Time RT-PCR. Neutrophil apoptosis were also assessed by flow cytometry.
Results :
Fas, FasL, CASP3, CASP8, CASP9, and BCL2 mRNA were higher in C57BL/6 mice infected corneas than normal corneas, on the contrary, BCL2 mRNA lower. After treatment with LOX-1 neutralizing antibody or LOX-1 inhibitor PloyI, the expression of Fas, FasL, CASP3, CASP8, CASP9, and BCL2 mRNA and TUNEL-positive cells in C57BL/6 corneas were significantly decreased compared with treatment with control IgG or control PBS. Neutrophils infiltration was significantly decreased after treatment with LOX-1 neutralizing antibody or LOX-1 inhibitor PloyI compared with IgG or PBS control. Fas, FasL, CASP3, CASP8, CASP9, and BCL2 mRNA were significantly decreased after treatment with LOX-1 neutralizing antibody or LOX-1 inhibitor PloyI compared with IgG or PBS control in neutrophils, correlated with significantly less neutrophils apoptosis.
Conclusions :
These data provided evidence that LOX-1 inhibition can reduce the expression of pro-apoptosis gene, Fas, FasL and anti-apoptosis gene, neutrophils infiltration and cornea cells apoptosis in fungal infected corneas of C57BL/6 in vivo. Meanwhile, LOX-1 inhibition can also reduce the expression of Fas,FasL, CASP3, CASP8, CASP9, and BCL2 mRNA and the apoptotic rates of neutrophils in vitro. Precis LOX-1 inhibition can reduce neutrophils apoptosis in C57BL/6 mouse cornea after A. fumigatus infection
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.