Fetal tendons and skin heal regeneratively without scar formation. Cells isolated from these fetal tissues exhibit enhanced
cellular migration and collagen production in comparison to cells from adult tissue. We determined whether fetal and adult
fibroblasts isolated from the anterior cruciate ligament (ACL), a tissue that does not heal regeneratively, exhibit differences
in cell migration rates and collagen elaboration. An in vitro migration assay showed fetal ACL fibroblasts migrated twice
as fast as adult ACL fibroblasts at a rate of 38.90 ± 7.69 μm per hour compared with 18.88 ± 4.18 μm per hour, respectively.
Quantification of Type I collagen elaboration by enzyme-linked immunosorbent assay showed fetal ACL fibroblasts produced four
times the amount of Type I collagen compared with adult ACL fibroblasts after 7 days in culture. We observed no differences
in Type III collagen with time for adult or fetal ACL fibroblasts. Our findings indicate fetal ACL fibroblasts are intrinsically
different from adult ACL fibroblasts, suggesting the healing potential of the ACL may be age-dependent.
One or more of the authors have received funding from a Whitaker Foundation Graduate Fellowship (SSS) and National Institutes
of Health Grant R21 AR051056 (SBN).
Each author certifies that his or her institution has approved the animal protocol for this investigation and that all investigations
were conducted in conformity with ethical principles of research.