Renal Capsule Tumor Xenografting: A Technique to Generate an Experimental Animal Model to Evaluate Prostate Carcinogenesis

Before beginning the surgical procedure, sterilize all necessary instruments and prepare the work area. Once the animal is properly anesthetized, disinfect the surgical site with repeated applications of betadine and alcohol.

After sterile drapes are applied to the area, a 2 to 3 centimeter dorsal midline incision is performed. Next, separate the underlying dermis from the body wall. Separate both sides of the incision for bilateral grafting or just one for unilateral grafting. Once separated, place the mouse into a lateral position and locate the kidney by viewing the renal profile through the muscle wall. Applying gentle pressure with the thumb and index finger may assist with visualizing the internal organs.

Using fine iris scissors and taking care to avoid major vessels and spinal nerves, make a 1 centimeter incision in the body wall parallel to the spine. Widen this incision to 1.5 to 2 centimeters by gently opening the scissors wider after placing them in the initial incision.

Exteriorize the kidney by applying gentle pressure outside the muscle wall on either side of the kidney. Next, tuck the skin edges below the exteriorized kidney, which will rest on the body wall. If other structures are also present, they can be gently tucked in. While the kidney is exteriorized, maintain hydration of the renal capsule by applying sterile saline.

Gently lift the kidney capsule and make a 2 to 4 millimeter incision. The size of the incision is determined by the size of the graft but should be minimized in order to maintain the integrity of the capsule. Insert the rounded closed end of the pipette prepared earlier under the capsule tangential to the surface of the kidney. Once inserted, gently open a small pocket for the grafts using great care not to damage the kidney parenchyma. Tissue grafts are prepared from fresh prostate tissue obtained during surgical resection.

Lift the cut edge of the kidney capsule and insert the graft into the pocket using the pipette tip. Several grafts can be placed under the kidney capsule and evenly spaced on the kidney surface. When grafting is complete, gently lift the sides of the muscle wall incision to replace the kidney back into the body cavity. Make sure that the grafts do not slip out from under the capsule.