Implanted in mice with injured livers, the bundle of human cells grew and expanded. Over the next three months, the cells took up routine liver tasks, producing proteins and grouping together in structures resembling those found in the organ.
The laboratory experiment, described in a paper published in 2017, suggested a new way to restore or repair damaged tissue.
To Sangeeta Bhatia and Christopher Chen, two of the paper's authors, the findings were an important step in advancing research they had dedicated the better part of two decades to.
"We were working on two sides of a really important clinical problem, which was how to deliver assemblies of functional cells into the body to support tissues," said Bhatia, director of the Center for Nanomedicine at the Massachusetts Institute of Technology.
Their progress led them two years ago to found a biotech company that on Wednesday officially launched as Satellite Bio, backed with $110 million in funding and helmed by the former head of Novartis' gene therapy business, Dave Lennon.
The company aims to translate the work of Bhatia, Chen and their cofounder Arnav Chhabra into "tissue therapeutics" — regenerative medicines built from bioengineered tissue structures, or "satellites," that can be implanted into patients.
Their ambition is broad. Satellite envisions developing therapies for rare disorders as well as more prevalent conditions. Initially, it will focus on liver diseases, Lennon said, but could eventually target metabolic diseases, severe obesity or even neurodegeneration.
While Satellite remains some distance from clinical testing, Bhatia and Lennon said the company is launching at the right time, building on advances in the adjacent cell and gene therapy fields and as investment in regenerative medicine increases.
"The marketplace is finally ready to receive these therapies — the regulators, the pharma [companies], even the payers," said Bhatia. "The whole ecosystem is now established. That wasn't the case when we started."
In addition to a growing list of approved cell and gene therapies, the Food and Drug Administration last year approved two donor-derived tissue products for a rare immune disorder and for thermal burns, for example.
Satellite's approach starts with a "seed" of cells, which are constructed into larger assemblies embedded within a degradable hydrogel that's designed to promote tissue engraftment.
According to Bhatia, her and Chen's research showed that the number and type of neighbors cells are grouped with are important characteristics. "That led to this platform technology where we realized we had all the tools to make cells functional by assembling them in collectives," she added.
Once implanted, the next challenge is encouraging blood vessels to grow into the implant, an area of research led by Chen, who is the director of the Biological Design Center at Boston University.
"We're not seeking to replace organs in the way that you see in organ transplants," Bhatia said. "These are little credit card implants and, because they're full of healthy functional cells, they can supply a booster function and support the restoration of healthy organs."
Satellite claims its approach can work with "virtually any type of cell," including induced, pluripotent stem cells as well as mature adult cells.
Manufacturing will be one of Satellite's top hurdles and an early focus as the company moves toward clinical testing. About 40% of the roughly 40 employees now at Satellite work in technical operations, according to Lennon.
"We really targeted a raise that would allow us to get into the clinic with our program, which includes scaling the company to clinical-grade manufacturing as well as … demonstrat[ing] proof of principle across multiple different cell types," Lennon said.
Joining Lennon on Satellite's executive team are Laura Lande-Diner, a serial entrepreneur and past cofounder of several biotech companies, and Tom Lowery, previously the chief scientific officer at T2 Biosystems. Lande-Diner was appointed chief business officer at Satellite, and Lowery chief technical officer.
Satellite's Series A round was led by Israeli venture capital firm aMoon Growth. AMoon was joined by prior seed investors Lightspeed Venture Partners, aMoon Velocity, Polaris Partners and Polaris Innovation Fund, as well as new investors Section 32, Catalio Capital and Waterman Ventures.
Founded right as the COVID-19 pandemic began, Satellite's fundraising took place as the market for biotech companies peaked and then crashed. The sustained downturn over the past year has forced some new startups to redraw their funding plans and contemplate staying private for longer.
Lennon acknowledged that shift in investor sentiment. "We are planning for a future where fundraising could be more difficult," he added, "and I think everybody needs to adapt to that."