Abstract
Purpose:
To investigate whether TLR activation regulates corneal hem- and lymph-angiogenesis.
Methods:
B6LY5 mice aortic ring explants were cultured for 5 d with the presence of 10ng/mL VEGF before TLR ligands 1-9 were added into culture media. Sprouting outgrowth was measured and compared between TLR ligands treated groups and water treated control group after 5 further days of culture. Corneal angiogenesis was induced by 3 Nylon corneal sutures on BALB/c mice before water, TLR3, TLR7 or TLR9 ligand was applied topically on debrided cornea at day 0, day 2, and day 4. The corneal vessel ingrowth was scored under surgical microscope after 7 days. The volumes of blood and lymphatic corneal vessels were quantified after whole mount immunofluorescence staining with CD31 and LYVE-1 antibodies.
Results:
TLR7 and TLR9 activation suppressed vascular outgrowth from aortic ring explants compared to control. TLR9 engagement inhibited corneal blood vessel ingrowth after 7 d post corneal suturing, while there was no difference between control and TLR3 and TLR7 treatment groups. TLR9 activation also decreased the volumes of blood and lymphatic corneal vessels compared to control.
Conclusions:
TLR9 activation could suppress aortic vessel sprouting in vitro as well as corneal hem- and lymph-angiogenesis in vivo.
Keywords: 480 cornea: basic science •
557 inflammation