Abstract
Purpose:
To examine the biological effect of interleukin-18 (IL-18) on retinal pigment epithelium (RPE) cell viability and choroidal neovascularization (CNV) in mice.
Methods:
Mouse recombinant (rIL-18) and neutralizing antibody for IL-18 were commercially purchased and resuspended with PBS. Subretinally mouse rIL-18 was injected. PBS injected eyes were used as control. Seven days after subretinal injection, fundus was checked and RPE was collected to examined cleaved caspase-3 expression in ELISA. Laser-induced choroidal neovascularizations (CNVs) were performed in the eyes of 6 week-old male C57Bl/6J mice, followed by intravitreous injection of 1ug rIL-18. The eyes injected with PBS after laser-CNVs were used as control. Neutralizing antibody for IL-18 (0.3ug) was also injected intravitreously after inducing laser-CNV. The eye injected with isotype control (0.3ug) was used as control. Seven days after laser and intravitreous injection, eyes were fixed with 4% paraformaldehyde, and stained with isolection B4. CNV volumes were analyzed using confocal microscope (Nikon).
Results:
The caspase-3 expression in the RPE of the eye injected with rIL-18 showed significantly higher than those injected with PBS. However, CNV volume in the eyes injected with rIL-18 did not show significant difference compared with those injected with PBS. Furthermore, CNV volume in the eyes injected with IL-18 antibody did not show significant difference compared with those injected with isotype control.
Conclusions:
These results indicated that IL-18 induced RPE cell death after subretinal injection, but did not show pro- or anti-angiogenic effects on laser-induced CNV in mice.
Keywords: 453 choroid: neovascularization •
701 retinal pigment epithelium