Biomaterials · Nov 2026
First use of a woven allogeneic vascular graft made of cell-assembled extracellular matrix (CAM) as an arteriovenous shunt in sheep: a pilot study
By Roudier G, Gluais M, Hourques M et al.
Reliable vascular access is vital for patients undergoing hemodialysis. Current arteriovenous shunts (AVS) made of expanded polytetrafluoroethylene (ePTFE) are prone to thrombosis, intimal hyperplasia, and infections. To overcome these limitations, biological Tissue-Engineered Vascular Grafts (TEVGs) were produced by weaving threads made from Cell-Assembled extracellular Matrix (CAM), i.e., extracellular matrix produced by ovine fibroblasts in culture. The woven TEVGs were designed with a 6 mm internal diameter and beveled ends to facilitate use as an AVS. They had a burst pressure (3069 ± 546 mmHg) and a compliance (4.4 ± 0.5 %/100 mmHg) closer to those of native blood vessels than ePTFE prostheses. Woven TEVGs were implanted as carotid-jugular AVS in sheep and compared to ePTFE controls in a bilateral model (n = 8 animals). Grafts were easily punctured with 16G hemodialysis needles once at 4 weeks without loss of structural integrity or hemorrhagic complications. Overall TEVGs patency was 100%, while it was 87.5% for ePTFE grafts (n = 8). Histological analysis revealed an inflammatory response that decreased between 4 and 8 weeks. A luminal neotissue was observed at 8 weeks with smooth muscle cells and localized endothelialization. Localized calcification of CAM was observed and appeared to be correlated with high tissue compaction. This proof-of-concept study demonstrates the feasibility of using a completely biological TEVG made from woven CAM as an AVS in an allogeneic large animal model. Future studies are needed to understand and avoid the never-before-observed calcification of the CAM in a large animal model, as well as to determine longer-term outcomes.