Technion Researchers Bioprint Blood Vessel Networks For Tissue Implants

Researchers from Israel’s institute of technology 3D printed a network of blood vessels able to supply blood to implanted tissue.

Headed by Techion professor Sculamit Levener,

the scientist 3D printed a tissue flap with a blood vessel network that for the first time according to the team,

contains a working combination of big and small blood vessels.

This progress could potentially eliminate the intermediary step of transplanting the issue first into a healthy limb of a patient to allow it to infuse the body’s blood vessels,

Before transplanting it into the afflicted area.
Additive manufacturing allows better customization for patients, and might help reduce the risk of implant rejection.

Blood vessels networks are very important for transporting oxygen and nutrients to the body’s tissues and organs.
Transplanted tissues need the help of blood vessels to reduce the risk of the body rejecting them and work successfully.

Technion is supported by the European Research Council under the EU’s horizon 2020 research and innovation programme.

Dr Ariel Szklanny hoped to develop a hierarchical blood vessel network for grafted tissues using 3D printing.
He started by 3D printing a polymeric scaffold that imitated the shape and size of a large blood vessel.
The scaffold was moulded in the form of a hollow tube with side openings to enable the connection of smaller blood vessels.

Compared to other studies where animal collagen was used to create scaffolds,

Szklanny applied human collagen developed by Israeli bioprinting firm Collplant stemmed from tobacco herbs.

Once the scaffold was created,

tissue is 3D printed and built using another collagen-based bio-ink, and a network of tiny blood vessels moulded inside.

Larger blood vessels are then covered with endothelial cells that make up the inner layer of blood vessels in the body.

the incubation period for the structure is not more than one week,

by this time scaffold has created working connections with smaller bioprinted cells in the surrounding tissue to imitate the hierarchical structure of a human blood vessel network.

Advancing tissue transplantation

To prove the working potential of the 3D printed blood vessel network,

Technion’s team grafted the tissue structure into a rat,

connecting to its femoral artery.
Blood was able to flow through the transplanted tissue through the blood vessel network perfectly.

The Techion team says,
The study is an important step towards personalised medicine and proves the potential of 3D Bioprinting.

Bioprinting allows large blood vessels of the same size and shape to be 3D printed and massed together with the tissue needed to be implanted.

Most importantly,

enabling the transplant of tissue with its blood vessel will eliminate the need to implant tissues inside a healthy part of the human body first so that it can be infused by the body’s cells,

before transplanting again in an affected area.
given that such tissue can be formed using a patient’s cells would also substantially reduce and even potentially eliminate,
The risk of the body rejecting the implant.

In the future,

The Technion team will determine the scalability and translatability of their approach by using bioprinted blood vessel networks to be implanted in larger animals, like pigs.
The team believe their method could create a new path toward full lab-grown specific tissues that are appropriate for transplantation.

3D bioprinting

3D printing processes have been used for the development of blood vessels imitating structures in the past,

Scientists are aiming to develop alternative methods for drug development,

reducing the need for animal and human testing and disease treatment.

In 2018,

scientists from CU boulder created a 3D printing process that uses controlled inhibition to mimic the structure and geometry of blood vessels.

The study’s purpose was to design microstructures that can be custom made for disease modelling.
Simultaneously,

Bioengineers from the University of California San Diego created a 3D bioprinting process to develop lifelike organ tissue models containing blood vessel networks.

the amazing thing about this network was it was able to keep breast tumours alive outside the body,

as well as making a model of a vascularized human gut.

Even more recently researchers from tel Aviv Israel created a viable brain tumour,

this research could pave the way to modelling the brain and other body parts before doctors actually operate on the human body.

Source: Advanced sciences, Youtube