Upper-extremity transplantation using a cell-based protocol to minimize immunosuppression

Area of Science:

• Immunology
• Transplantation Surgery
• Regenerative Medicine

Background:

• Reconstructive transplantation is limited by immunosuppression risks.
• A novel donor bone marrow (BM) cell protocol was developed to minimize immunosuppression in upper-extremity transplantation.
• The
• Pittsburgh protocol
• aims to improve the risk-benefit balance of hand and forearm transplants.

Observation:

• Five patients underwent upper-extremity transplantation (hand/forearm) between 2009-2010.
• Induction involved alemtuzumab and methylprednisolone, followed by tacrolimus monotherapy.
• Donor BM cells were infused on day 14 post-transplant.

Findings:

• Patients were maintained on low-dose tacrolimus monotherapy (4-12 ng/mL).
• Infrequent, reversible skin rejections and no infections were observed.
• Sustained functional improvements (motor, sensory) and patent vessels were noted, with minimal side effects.

Implications:

• The BM cell-based protocol is safe and well-tolerated for upper-extremity transplantation.
• This approach allows for reduced immunosuppression, specifically low-dose tacrolimus monotherapy.
• This strategy may enhance the feasibility and safety of reconstructive transplantation procedures.