Chronic rejection in vascularized composite allotransplantation

Area of Science:

• Transplantation immunology
• Regenerative medicine

Background:

• Vascularized composite allografts (VCA) restore damaged body parts.
• Acute skin rejection is common in early VCA post-transplant.
• Chronic rejection, previously unknown in human VCA, is now observed.

Purpose of the Study:

• To review the current understanding of chronic rejection in VCA.
• To highlight diagnostic challenges and potential new methods.
• To identify knowledge gaps and future research directions.

Main Methods:

• Review of recent findings on VCA chronic rejection.
• Analysis of immune and nonimmune mechanisms.
• Evaluation of diagnostic approaches including imaging.

Main Results:

• Chronic rejection targets skin and vessels, causing graft dysfunction and loss.
• Diagnosis is challenging, relying on clinical signs, biopsies, and emerging imaging.
• Both immune and nonimmune factors contribute to chronic rejection.

Conclusions:

• Understanding and defining chronic rejection in VCA is crucial.
• Improved diagnostic criteria and treatment strategies are needed.
• Future research should focus on prevention via tolerance induction.