3D-Printed Fat Tissue Survives 150 Days in Animal Study

Researchers Test New Approach for Soft Tissue Repair

Scientists in Sweden explored whether fat tissue from liposuction could be 3D-printed and used for soft tissue reconstruction. This matters because current fat grafting techniques often face problems with tissue survival. The body can reabsorb a significant portion of transplanted fat over time. The research team wanted to understand what makes fat tissue survive—and whether 3D printing could offer a better solution.

Fat Tissue Contains Multiple Types of Healing Cells

The researchers analyzed human fat tissue collected through liposuction. They found it contains several important cell types that support healing. These include adipose-derived stem cells (regenerative cells found in fat), pericytes (cells that help blood vessels function), and endothelial progenitor cells (young cells that can form new blood vessels). This combination of cells creates a natural environment for tissue repair and growth.

Over 6,000 Proteins Found That Support Tissue Survival

Using advanced protein analysis, the team identified more than 6,000 different proteins in the fat tissue. Many of these proteins play important roles in healing:

• Adipokines that regulate fat cell development and blood vessel formation

• Growth factors that help cells multiply and tissues regenerate

• Angiogenic proteins that promote new blood vessel growth

• Proteins involved in cell differentiation that help stem cells become specific tissue types

Some proteins had never before been described in human fat tissue under the skin.

3D-Printed Grafts Maintained Shape for Five Months

The research team mixed the fat tissue with a special gel containing alginate and nanocellulose. This allowed them to 3D-print the tissue into specific shapes. They then transplanted these printed constructs into mice. The grafts survived for 150 days—about five months. Importantly, the printed structures kept their original shape and size throughout this period. This addresses a major challenge in current fat grafting, where tissue often shrinks after transplantation.

Human Blood Vessels Grew Inside the Grafts

Perhaps the most exciting finding involved blood vessel formation. The researchers found human blood vessels inside the grafts at both 30 days and 150 days after transplantation. This suggests the fat tissue could generate new blood vessels from the tiny capillaries it contained. Blood supply is critical for graft survival. Without proper blood flow, transplanted tissue cannot get the oxygen and nutrients it needs to survive long-term.

What This Means for Future Soft Tissue Treatment

This animal study provides important evidence that 3D-printed fat tissue has potential for soft tissue reconstruction. The ability to create custom-shaped grafts that maintain their form could help surgeons repair defects more precisely. The presence of stem cells, blood vessel-forming cells, and thousands of supportive proteins creates favorable conditions for healing.

While this research was conducted in animals, the findings suggest a promising direction for human treatment. The fat tissue used came from human donors, and its cellular makeup appears well-suited for reconstruction purposes. Future studies will need to confirm these results in human patients before this approach becomes widely available.

For patients considering regenerative treatments, this study highlights why fat tissue is a valuable source of healing cells. The natural combination of stem cells, blood vessel components, and growth-promoting proteins may support better outcomes in tissue repair.

Source: Säljö et al., Adipocyte, 2022.