Three-Dimensional Collagen Matrix Scaffold Implantation as a Liver Regeneration Strategy

This method involves placing an implant of collagen matrix as a scaffold in the liver to promote liver regeneration. This implantation method has opened the door for a strategist exploring the restoration of the shape and balloon of the resected tissues, thereby reducing anesthesia, surgical duration, and recovery time. This method can be used to promote regeneration involving models of liver fibrosis, as well as other mammalian species.

This method is based on tissue engineering and regenerative medicine to promote the restoration of injured tissue. Begin by sanitizing the surgical area work table, microsurgery microscope, and seat with a 2%chlorhexidine solution, then hydrate the collagen matrix scaffold obtained from a bovine condyle in sterile saline solution for 20 minutes. Next, using surgical soap and a double-edged blade, shave the abdominal skin of an anesthetized six to eight-week-old male Wistar rat, then disinfect the skin three times using a 10%povidone iodine solution.

Place the animal on a warm plate in the decubitus dorsal position with the neck hyperextended to maintain a permeable airway. Evaluate the depth of anesthesia through the respiratory pattern and loss of withdrawal reflex in the limbs. Then place a disposable surgical drape around the shaved skin and using the xiphoid process as a reference point, make a 2.5 centimeter incision on the alpis line with dissection forceps, taking care to avoid the abdominal wall blood vessel to prevent bleeding.

After placing the abdominal retractor, observe the abdominal cavity. Using the dissection forceps, extract the left liver lobe and place it on the metal plate. Using a sterile one by one by one centimeter triangular metallic template, perform a hepatectomy.

To prevent bleeding of the liver, maintain surgical compression with a swab on the edge of the liver for five minutes. Next, using 7-O non-absorbable polypropylene sutures, implant the hydrated collagen matrix scaffold in the hepatectomy site with four stitches between the liver tissue and the scaffold to prevent displacement of the biomaterial. Return the liver to the abdominal cavity and suture the abdominal wall and skin with a 3-O nylon suture.

Clean the surgical incision twice with a surgical iodine-soaked sponge and monitor the vital signs of the animal. Then place the animal in lateral decubitus position. After administering an analgesic, place the animal in an individual polycarbonate box with laboratory animal bedding in a noise-free area with temperature control.

Observe the recovery from anesthesia and monitor water and food consumption for two hours. There was no difference in the liver function between the SHAM group and the experimental groups with and without the collagen matrix scaffold at three, 14, and 21 days, indicating that the collagen matrix scaffold does not disrupt liver function. Histological analysis on day three shows that the presence of the collagen matrix scaffold in the liver did not promote a foreign body reaction and the conspicuous presence of lax connective tissue is observed.

On days 14 and 21, the lax connective tissue is more abundant with the collagen matrix scaffold trabeculae surrounded by hepatocytes suggesting that hepatocytes have migrated to the collagen matrix scaffold. Areas of hepatocytes irrigated by a vessel can be seen and the hepatocytes adhering to the collagen matrix scaffold trabeculae are sometimes surrounded by lax connective tissue. While performing the hepatectomy, use aseptic technique to avoid infection and apply compression afterwards to prevent bleeding from the liver.

Also, use 7-O sutures for implantation of collagen matrix scaffold to avoid tearing. After implantation of the collagen matrix scaffold in a fibrotic animal model, the advantages of sinogenic implantation for liver regeneration can be evaluated. The use of collagen matrix scaffold to replace the liver extubated mass has not been evaluated until now.

These genogenic materials paves the way as another therapeutic option in the field of the chronic liver diseases.