Our group has demonstrated elevated serum concentrations of platelet-derived growth factor- (PDGF-) AA, a mediator of vascular remodeling, and brain derived neurotrophic factor (BDNF), a biomarker of cerebral ischemia, in children with hemoglobin SS and high TCD velocities [64], consistent with the model. Here, BDNF is linked to Cerebral ischemia.