The Biological Features Of Fibroblasts From The Knee Joint Ligaments And The Effect Of Growth Factors On Its Proliferation

Objective: To analyze the biological features of fibroblasts from the knee joint ligaments and to observe the effects of acid fibroblast growth factor (aFGF), basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), endothelial cell growth factor (ECGF) on the proliferation of the fibroblasts from the knee joint ligaments.Methods: Fibroblasts from the anterior cruciate ligament (ACL) and the medial collateral ligament (MCL) of New Zealand white rabbits, aged 10-12 weeks, were cultured by collagenase digestion or primary explant technique, and ACL cells from the human knee joint were cultured as well. We optimized conditions for maintaining them in culture, and observed biological features of fibroblasts from the knee joint ligaments. While aFGF, bFGF, EGF or ECGF were added to the cell culture media, the cellular proliferation was assayed by XTT method.Results: The maximal growth for all these cells were obtained with Dulbecco s modified Eagle s medium supplemented with 10% fetal bovine serum. Morphology of both ACL and MCL cells from New Zealand white rabbit was alike in vitro, they both had fibroblast phenotype, but MCL cells grew faster than ACL cells. Rabbit ACL and MCL cells produce the same total amount of collagen in vitro culture, but the ACL cells produced more type I and less type III collagen than the MCL cells did. ACL cells from human knee joint had fibroblast phenotype in vitro, too. The expressions of type I collagen, type III collagen and fibronectin were shown on ACL cells from human proven by immunocytochemistry. aFGF, bFGF, EGF, ECGF enhanced the proliferation of both MCL and ACL cells from New Zealand white rabbits significantly at the dose we tested, and the effect was dose-dependent, but its efficacy reached a plateau when presented at greater concentrations than the dose with the greatest efficacy.Conclusion: 1. Fibroblasts from the knee ligaments were cultured successfully invitro by collagenase digestion or primary explant technique. 2. The biological features of rabbit fibroblasts from the medial collateral ligament vary with that from anterior cruciate ligament, this difference can contribute to explain the distinct responses of the two tissues in the injury situation. 3. It is evident that aFGF, bFGF, EGF or ECGF can enhance the proliferation of the ligament fibroblasts from the knee joint significantly.