The Use of Autologous Fibroblasts for the Reconstruction of the Anterior Cruciate Ligament Tears

Surgical reconstruction using an autologous or allogenic allograft is the treatment of choice for anterior cruciate ligament (ACL) tear repair. We have checking the treatment of ACL tears with in vitro cultured autologous fibroblasts on porcine type I/III collagen membranes, in 12 sheep randomly assigned to be treated with collagen membrane without cells or with porcine membrane plus 5 million autologous fibroblasts per cm2. The animals underwent a first surgery in which a biopsy of the ACL was taken, and a second one in which the membrane was implanted alone (N=6) or with the fibroblasts (N=6) isolated from the biopsy. After 16 weeks, the animals were sacrificed and samples of healthy and repaired ACL were taken for histological and gene expression of type I collagen (COL1), MMP-13 (matrix metallopeptidase 13), and tenascin-C (TNC) studies. The architecture of normal ACL was not conserved either in the ACL treated with the membrane with or without cells. However, a higher degree of peripheral vascularization was observed in the ACL treated with membrane plus fibroblasts than in those treated with membrane alone. Cellularity and nucleus volume were significantly higher in the center or the periphery of the neo-formed ACL than in the control ACL. No differences between the ACL treated with membrane alone or with membrane plus cells were observed in the relative COL1, MMP-13 and tenascin-C expression. Fibroblasts embedded in porcine type I/III membranes probably enhance vascularization of the graft, so it could be a promising tool for the treatment of ACL tears.