Figure 14.

CXCL16 induces proliferation, phosphorylation of ERK1/2 and angiogenic sprouting in human retinal microvascular endothelial cells (HRMECs). HRMECs were stimulated with control medium alone or control medium with varying concentrations of CXCL16 (1 to 10 ng/ml) or with 10 ng/ml VEGF as a positive control. The number of metabolically active cells was quantified after 48 h using the ATPlite assay and expressed relative to control. (n=2 to 4, in quadruplicate) (A). The amount of phospho-ERK1/2 in HRMECs stimulated with CXCL16 (1 or 5 ng/ml) or VEGF (30 ng/ml) for 15 min was measured through enzyme-linked immunosorbent assay (ELISA). Relative phospho-ERK1/2 levels compared to unstimulated control are shown. (n=4, in duplicate or triplicate) (B); HRMEC spheroids were treated with medium (control), 0.3 or 3 ng/ml of CXCL16. After 14 h of incubation, spheroid sprouting was assessed in two independent experiments. Representative images of a control spheroid and a spheroid stimulated with 3 ng/ml CXCL16 are shown (C). For each condition (control, n=17; 0.3 ng/ml, n=17; 3 ng/ml, n=14), the number of sprouts per spheroid was counted (D). All results are expressed as median (interquartile range) ((*p < 0.05, **p < 0.01,***p < 0.001, ****p < 0.0001, Mann-Whitney test).