Amniotic Fluid, Cells, and Membrane Application

Orthobiologics is a rapidly growing field, as the potential of stem cells becomes better understood. Amniotic tissue has a long history of clinical use and its anti-inflammatory and paracrine function makes it an attractive source for cells. The use of amniotic membrane for cartilage damage has been evaluated primarily in preclinical settings. Multiple in vitro studies have shown that amniotic membrane and amniotic mesenchymal stem cells can produce a chondrocyte phenotype with accumulation of glycosaminoglycans, collagen, and chondrogenic markers. Both autologous and allogeneic sources are available, with the latter having the benefit of decreased morbidity to the patient. A wide array of placental-derived allograft tissue forms are currently available in both tissue and injectable formats. Sheets generally consist of one or more intact layers of placental membrane, namely amnion, amnion and chorion, double layer amnion, or umbilical cord. Liquid products consist of morselized tissues such as amnion or chorion or both, suspensions containing cells such as amniotic fluid stem cells, purified variants of amniotic fluid, or some combination. Clinical and basic science investigations are underway to define the cellular mechanisms of action and appropriate clinical indications for the use of these placental-derived products.