Cryopreservation Maintains Structural Integrity and Biomechanical Properties of Human Rectus Fascia for up to 1 mo

Abdominal wall closure after transplantation is crucial to reduce morbidity and to ensure graft and patient survival, but it often remains challenging. Donor nonvascularized rectus fascia (NVRF) allotransplantation offers a valuable solution when primary closure fails. Despite the growing clinical use of NVRF, standardized protocols for NVRF preservation are lacking. This study evaluates the impact of short-term cold storage at 4 °C (8 d) and long-term cryopreservation (1 mo and 6 mo) on human NVRF at the mechanical, histological, and microbiological levels.

NVRF was obtained from 10 human donors (6 men; 6 donation after circulatory death III; 4 donation after brain death; age 56 y [26-68 y]; BMI 28 kg/m² [23-31 kg/m²]). Fresh tissue was compared with 3 preservation methods: (1) cold storage in Institute Georges Lopez-1 solution at 4 °C for 8 d; (2) 1 mo cryopreservation; and (3) 6 mo cryopreservation at -80 °C. For each condition, the analysis included uniaxial tensile testing, histological evaluation based on hematoxylin and eosin and picrosirius red staining, and microbiological analysis for yeast and bacteria.

After 8 d at 4 °C, ultimate strength and rigidity were reduced, whereas histological structure appeared intact. One month of cryopreservation showed no indications for altered mechanical or histological characteristics compared with fresh tissue. After prolonged cryopreservation for 6 mo, extensibility was increased. Yeast contamination was absent in all samples, and commensal bacteria were detected in 17 of 40 fresh and preserved samples, without impact of the preservation method.

In conclusion, cryopreservation at -80 °C maintains biomechanical characteristics and structural integrity of NVRF for up to 1 mo, offering a promising method for prolonged NVRF preservation in clinical applications.