Systemic upregulation of PDGF-B in patients with neovascular AMD

To determine the plasma levels of platelet-derived growth factor-B (PDGF-B), VEGF, and TNF-α in patients with neovascular AMD and in patients with diabetic macular edema (DME).

Thirty patients with neovascular AMD, 30 patients with DME, and 12 healthy controls were included in this prospective study. The concentrations of PDGF-B, VEGF, and TNF-α were measured by ELISA.

The PDGF-B concentration in the plasma of controls was (median [25th-75th percentile]) 263.5 (162.0-513.3) pg/mL and in patients with DME 219.0 (122.8-604.8) pg/mL. In patients with neovascular AMD, PDGF-B levels were significantly higher with a median plasma concentration of 783.5 (289.3-1183.5) pg/mL (P = 0.003). The VEGF concentrations in patients with DME 33.0 (21.8-73.0) pg/mL and in patients with neovascular AMD 55.0 (37.0-116.3) pg/mL showed no significant differences (P = 0.159). A positive correlation of PDGF-B and VEGF plasma levels was found in patients with neovascular AMD and in patients with DME (r = 0.683, P < 0.001, and r = 0.612, P < 0.001, respectively). No significant differences of systemic TNF-α levels could be found between the three study groups.

Patients with neovascular AMD have significantly higher plasma PDGF-B levels compared with patients with DME and healthy controls. Our study data indicate that PDGF-B may be involved in the pathogenesis of neovascular AMD. (https://eudract.ema.europa.eu number, EudraCT 2010-024654-11)