Endogenous cell source for healing of the tendon-to-bone interface by GF-embedded scaffolds. One week post-operatively, implantation of scaffolds +GF resulted in abundantly more CD146+ cells in the healing area and in the scaffolds (a)â(e) compared with âGF (f)â(j) (asterisk indicates scaffold structure) (T, tendon; B, bone, I, interface).