Purpose: Treatment for a large abdominal wall defect remains challenging. The aim of this study was to optimize tissue engineering therapy of muscle constructs using a rat model.
Methods: Experimental abdominal wall defects were created in Wister rats. The animal model was divided into three groups: collagen sponge (CS), hybrid scaffold (HS) and hybrid scaffold containing bone marrow liquid (HSBM). Hybrid scaffolds comprised collagen sponge and poly L-lactide (PLLA) sheets. Abdominal wall defects were covered by three kinds of sheets. Thereafter, the bone marrow liquid was spread onto the sheets. Rats were killed at 4, 8, and 16 weeks. Pathological examinations were performed using hematoxylin-eosin and desmin antibody staining.
Results: The CS group showed abdominal hernia, whereas the HS and HSBM groups did not. Vascular formation was confirmed in all groups. Muscle tissue was recognized at the marginal area of the sheet only in the HSBM group.
Conclusion: The HS and HSBM groups show a greater intensity than the CS group. Muscle tissue regeneration is solely recognized in the HSBM group. Our experimental data suggest that the triad of scaffold, cell, and growth factor is fundamental for ideal biomaterials. The HSBM may be useful for reconstruction of abdominal wall defects.
Keywords: Bone marrow liquid; Gastroschisis; Omphalocele; Poly L-lactide; Regenerative medicine; Tissue engineering.