Abstract
Purpose :
We investigate the therapeutic effect of Programmed Death Ligand 1（PD-L1）by downregulating autoreactive T cells on experimental laser-induced choroidal neovascularization (CNV) in mice.
Methods :
After CNV was induced by laser photocoagulation in 200 female C57BL/6 mice, PD-L1, anti–PD-L1 antibody or PBS was injected by tail vein on 14th day after laser injury. Fluorescein angiography was performed on the 3rd day, the 7th day, the 14th day and the 21st day to grade CNV leakage after injection. The CNV volume was measured by confocal microscopy in eyes enucleated 3 days, 7 days, 14 days and 21 days after injection. Immune cells in peripheral blood were measured by flow cytometry.
Results :
Tail intravenous administration of PD-L1 significantly suppressed CNV leakage and CNV volume (P < 0.01). PD-L1 treatment inhibited lymphocyte proliferation and altered T cell differentiation by inducing decrease in IFN-γ+CD4+ Th1 cells and IL-17+CD4+ Th17 cells and increase in Foxp3+CD4+ regulatory T cells. The administration of anti–PD-L1 antibody produced the opposite effects to those of PD-L1 in CNV mice.
Conclusions :
Tail intravenous administration of PD-L1 suppressed laser-induced CNV by its anti-inflammatory and alteration of T cell differentiation. The current results suggested that PD-L1 may be a potential therapeutic adjuvant for treating CNV.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.