Panoply™ Human CD46 Knockdown Stable Cell Line

Loss of CD46 has recently been shown to be associated with choroidal neovascularization in mice. Here, researchers investigated the role of nitrite modification of the extracellular matrix (ECM) as an in vitro model of aging and its effects on CD46 expression and vascular endothelial growth factor (VEGF) release in co-cultured human retinal pigment epithelium (RPE). Results showed that CD46 was expressed on the basolateral surface of ARPE-19 cells grown on RPE-derived ECM. Nitrite modification of the ECM reduced CD46 expression in ARPE-19 cells by 0.5-fold and increased VEGF release by ARPE-19 cells by 1.7-fold. CD46 knockdown also increased VEGF release from the apical and basal surfaces of cultured ARPE-19 cells by 1.3-fold and 1.2-fold, respectively. Thus, nitrite-modified ECM reduced CD46 expression and increased VEGF release in ARPE-19 cells. Alterations in CD46 expression may lead to changes in VEGF and play a pathological role in the development of age-related macular degeneration.

To investigate whether CD46 plays a functional role in VEGF activation, researchers knocked down CD46 gene expression using siRNA. CD46 siRNA treatment significantly reduced CD46 expression (Figure 1A). In CD46-knockdown ARPE-19 cells, VEGF release from the apical surface was significantly increased by 32% compared with the random siRNA group (Figure 1B, left panel). Similarly, VEGF release from the basolateral surface of CD46-knockdown ARPE-19 cells was significantly increased by 19% compared with the random siRNA group (Figure 1B, right panel).

Figure 1. CD46 knockdown affected the release of VEGF in ARPE-19 cells. (Fields M A, et al., 2015)