Effects of interleukin-17 on human retinal vascular endothelial cell capillary tube formation in vitro

The present study aimed to investigate the effect of and mechanism underlying interleukin (IL)‑17 on human retinal vascular endothelial cell (HREC) capillary tube formation in vitro. The expression of IL‑17 receptor (IL‑17R) in human HRECs was quantified using reverse transcriptase‑polymerase chain reaction (RT‑PCR) and western blot analyses. The roles of IL‑17 in HREC migration and capillary tube formation were detected using a wound scratching assay and three‑dimensional Matrigel assay, respectively, in vitro. HREC proliferation was examined using a cell counting kit‑8 assay with administration of serial doses of IL‑17. The effects of IL‑17 on the expression of vascular endothelial growth factor (VEGF), intercellular cell adhesion molecule (ICAM)‑1, IL‑6 and IL‑8 in HRECs were evaluated using RT‑PCR and western blot analyses. The results revealed that the HRECs expressed IL‑17R, and the number of intact capillary tubes formed by HRECs in the presence of IL‑17 was markedly higher, compared with that in the blank control group. The wound scratching assay showed that the numbers of migrated HRECs stimulated with IL‑17 at concentrations of 100 or 500 ng/ml were significantly higher, compared with the number in the control group. The RT‑PCR and western blot analyses showed that IL‑17 significantly promoted the expression of VEGF, ICAM‑1, IL‑6 and IL‑8 by the HRECs. The proliferation of HRECs in the presence of IL‑17 was also significantly increased. Therefore, IL‑17 increased HREC capillary tube formation through promoting HREC migration, proliferation, and expression levels of VEGF, ICAM‑1, IL‑6 and IL-8.