Title : A resorbable and biomimetic 3D-printed natural hydrogel scaffold driving large-volume soft tissue repair: evidence from a large animal study
Abstract:
Breast cancer is the most common form of cancer in women, often requiring total mastectomy. In the US, 38% of affected women undergo this procedure (1), yet only 33% opt for reconstruction (2). Despite the availability of multiple reconstruction methods, a study conducted in the US between 1998 and 2007 reported that 45% of women who underwent mastectomy chose not to proceed with reconstruction (3), primarily due to concerns about postoperative sequelae, the need for multiple surgeries, and the use of synthetic implants. Recent advances in 3D printing and regenerative medicine have paved the way for a novel approach: 3D-printed scaffold implants designed to promote autologous tissue ingrowth. Our team has developed a 3D-printed biomimetic prosthesis made from a hydrogel composed of natural, biologically derived materials. This scaffold temporarily provides volume and shape to soft tissue while promoting cell colonisation. In vitro, it demonstrates a favourable cytotoxicity profile and supports tissue ingrowth by several biologically relevant cell types, including adipocytes, fibroblasts and endothelial cells, resulting in the formation of connective tissue. In vivo rodent studies have shown that the bioprosthesis promotes neovascularisation, is well tolerated, and degrades over time, leaving behind functional autologous tissue. Bioprostheses ranging from 75 to 300 cc were implanted in large animals and followed for up to 8 months. Long-term and scale-up studies demonstrated that the implant is easy for surgeons to handle, maintains its softness and mechanical resistance, and exhibits good tolerance and performance. No necrosis (a common complication) or significant capsule formation around the prosthesis was observed. Progressive resorption kinetics and central tissue colonisation with non-inflammatory fibroconnective tissue were noted (Figure 1). This 3D-printed bioprosthesis offers a biomimetic and safe alternative for breast reconstruction by promoting natural tissue regeneration. It maintains volume over time with good tolerance and no complications. These results support its potential for future clinical applications.
Keywords: Tissue Engineering, Soft Tissue Regeneration, Regenerative Medicine, Breast Reconstruction, Preclinical Model, Large Animal
