Imagine you’re building a house from scratch. You know the basic components you’ll need: foundation, framework, walls, a roof, plumbing and electricity, to name a few.

But there’s a lot more that goes into the process. How do you wire each room for electricity and connect the plumbing? How do you hook up to nearby utility services? In short, how can you combine each of these components into a fully functional unit?

In a way, this is the same challenge facing researchers who are working to bioengineer new organs. While they have been successful in reseeding stripped down organs with new cells, there’s still a long way to go before that organ becomes a functional unit.

Wafa Altalhi, PhD, a postdoctoral fellow in the Ott Lab in the Center for Organ engineering, is working on strategies to rebuild what can be considered the plumbing system of the organ—the blood vessels that bring nutrients to the cells and connect it to the rest of the body.

Altalhi, a Saudi Arabian scientist , was one of four postdoctoral female scientists to receive the L’Oreal-UNESCO Women in Science Middle East Fellowship in 2019.

The fellowship is a global program that recognizes outstanding women in science and highlights their contributions to scientific progress.

The Promise and Challenges of Bioengineering

Bio-engineered organs could fill a critical medical need by providing patients in need of a transplant with organs recreated from their own cells. This would reduce the demand and wait times for donor organs and, for the best hope, could eliminate the need for transplant recipients to take immunosuppressive drugs.

To bioengineer an organ, researchers first take a nonviable donor organ and strip it of its existing cells so that only the extracellular matrix (the framework) remains.

Then they take cell samples from the would-be recipient, convert them into multipurpose starter cells called induced pluripotent stem cells (iPCS), and prompt them to differentiate into the cells that comprise the desired organ.

The cells are then seeded back onto the matrix in a way that is designed to replicate the structure of a fully formed organ. But it’s not enough just to put the pieces back together. The organ has to be able to thrive within the body, and that requires a steady and reliable blood supply.

Dr. Altalhi is investigating new ways to improve the production and viability of blood vessel cells in bioengineered lungs. This includes endothelial cells (the cells that line the interior walls of the vessels) and pericytes (contractile cells that help manage blood flow).

While the work is exciting and the potential is huge, she knows there’s a long road ahead. “Although we’re closer than before, we are not even near making a complete organ that resembles what we are born with,” she says. “It’s a work in progress but has a lot of promise.”

Altalhi is working on several projects to improve the viability of bioengineered blood vessels, including:

• Perfecting cell differentiation techniques to more accurately the replicate the different cells within blood vessels
• Creating a media culture that best supports the growth of the cells in the lab
• Identifying the best way to flow that media through the cells once they are seeded onto the lung so they stay viable
• Devising a strategy to introduce the cells to shear stress—the pressure caused by liquid flow—so they are ready to accommodate blood flow in the body

From Saudi Arabia to Mass General

Altalhi came from a large and highly educated family of 11 members all of whom are either working in or pursuing advanced degrees in science, medicine or education.

She was drawn to medical research with the hoping of finding new strategies with the hope of finding new strategies to improve vascular bypass surgeries and reduce ischemia complications related to diabetes, which has a high prevalence in Saudi Arabia and worldwide in general.

Her scientific journey has taken her to graduate school at the universities of Ottawa and Toronto before coming to Mass General to work as a postdoctoral fellow in the Ott Lab.

“Mass General has been my best experience so far,” she says. “I see scientists like Dr. Ott who sits at the intersection of academia, field work and entrepreneurship, and its inspiring that people are so committed to translating their science to products that can help patients.”

“It’s rewarding to investigate science for the sake of knowledge but translating that knowledge into a product for patients is helping more.”

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