AUTOLOGOUS GROWTH FACTORS FROM A SELF-CONTAINED, AUTOMATED, INTRA-OPERATIVE DEVICE

Abstract

Autologous growth factors or AGF is a technology that uses the patient’s own platelets as a source of growth factors. The platelets are super concentrated and then de-granulated to release mitogens, such as TGF-beta, PDGF, IGF, FGF and VEGF. AGF can be used alone as a source of signaling factors or it can be used with a variety of bone grafting materials, including autograft, allograft or porous ceramics. AGF is advantageous because it is completely autologous and obtained at the point of care in the operating room. AGF has been shown to be successfully collected by pheresing or separating the whole blood into its components to capture the buffy coat (i.e., platelets and white cells) using a conventional cell washer. To assure a predictable two to four fold increase in platelets and white cells over the peripheral blood concentration, the operator of the cell washer must follow a defined protocol. The buffy coat is then transferred to a processor containing an ultra concentrator. This achieves a further three fold concentration of platelets and white cells, as well as a three fold concentration of fibrinogen. This process can be effectively achieved using a single unit (approximately 450cc) of blood which produces approximately 60cc of autologous growth factors (AGF). The excess plasma and red cells can be returned to the patient.

We have developed as self-contained, electromechanically, software driven, turnkey device that separates and concentrates to produce AGF from as little as 100 cc of the patient’s whole blood. The device is the size and weight of a portable, tabletop clinical centrifuge. A single disposable, pre-sterilized cartridge is inserted into a centrifuge and automatic pumps. After the operator attaches the blood bag and provides minimal input, the machine automatically provides 10–15 ml of AGF. Total processing time is less than 15 minutes. Multiple, simultaneous cycling can process up to 450 ml of blood with operating times comparable to our contemporary system. Using human blood, the concentrations of platelets, white cells, and fibrinogen was comparable to the contemporary system. The AGF platelets were then de-granulated into a fibrin gel using either xenogenic or autologous thrombin. Consequently, the concentrations of TGF-beta, PDGF, IGF, FGF and VEGF were approximately 10 fold greater than blood levels and comparable to the separate component system.

We believe that we have developed a method and device that safely, simply, cost-effectively produces intra-operatively clinically relevant levels of autologous growth factors from 100 ml of autologous blood.