In the eight-year history of IndieBio, there are many incredible companies that have become global leaders of their sector. But the fastest-growing startup of them all is a relative newcomer, Prolific Machines, which was born in the basement of IndieBio’s San Francisco lab during COVID. Just two-and-a-half years old, Prolific Machines has raised over $52 million in funding from some of the most-respected investors in the world. 

Once upon a time – it was 2016 – Deniz Kent was a stem cell biologist getting his PhD in London at King’s College. His family was from southern Turkey, a city called Antioch, near the border with Syria. His mom and his family began sending him pictures of the refugees fleeing across the border into Turkey. Civil war in Syria had triggered a massive refugee crisis, so big in scale, it’s hard to imagine. 

Deniz’s mother began volunteering in the refugee camps, and Deniz felt the call to help.  

By the time Deniz arrived, more than 2.5 million Syrians had fled to Turkey, and another million would follow. Antioch soon had as many refugees as local citizens. People lived under carpets and blue plastic sheets, and then in endless rows of shipping containers. The experience had a deep effect on Deniz, and he began to question how his skillset in stem cell biology could help prevent situations like this. 

In the future, Deniz knew, refugees wouldn’t just be fleeing war and conflict and oppression. They would be fleeing the worst climate-impacted areas, whether from flooding or heat or agricultural system failure. Back in London, Deniz read regularly about these predictions – up to 1.2 billion people could become refugees by 2050. He felt he needed to do something about climate change. But he was a stem cell biologist focused on curing liver disease. How could he help?

The founder of IndieBio, Arvind Gupta, often said that the best startup founders are radicalized. They have borne witness to some injustice that makes them more driven. 

From afar, Deniz watched IndieBio fund the world’s first venture-backed cultured meat company, and then several more. He read about how cultured meat could help eliminate emissions from the livestock sector. And most of the scientists working in cultured meat were converted stem cell biologists. 

Deniz’s journey to IndieBio had begun – but his first interaction with IndieBio was still years away. 

In 2019, The Good Food Institute, a nonprofit think tank, published a seminal report that helped the world understand the real challenge of scaling cultured meat into a major industry. 80% of the cost of growing cells was in the cell media – the bath the cells swim in – and it contained two key signaling molecules that told the cells to grow. But making these growth factors was very expensive; they were as expensive as drugs. 96% of the costs of the media were in just those two growth factors. At the time, the cost of making a pound of meat in a large bioreactor cost just under $1,000, and up to $960 of that was in the growth factors. Many startups were working on ways to produce those growth factors less expensively. But Deniz had been considering a radical idea to get cells to grow without using any growth factors at all. 

The company is, to this day, secretive about how they do it (and this article won’t disclose it). But suffice it to say, Prolific’s approach was entirely novel – something nobody had ever tried before. And Deniz had no proof it would work; he had done no experiments. But he had to recruit a team on the idea alone. 

At the time, Max Huisman, originally from the Netherlands, was pursuing his PhD in biomedical sciences at the University of Massachusetts when Deniz sat down beside him at a dive bar. Deniz was in town for PhD research, got bored on a Friday, and showed up at a going away party for someone he didn’t know.

It’s safe to say that had Po [IndieBio] not existed, there is a good chance Prolific would not exist today.

Deniz Kent, Co-Founder and CEO, Prolific Machines

Deniz asked Max about his research. “I build super resolution cryogenic microscopes,” said Max, who couldn’t believe how interested Deniz was in his work. Deniz realized that Huisman’s skillset was perfect for the systems they’d need to engineer. Deniz pitched him on mass-producing cultured meat and landed his first co-founder. 

Deniz also needed a software expert, so he emailed a long pitch to his childhood friend Declan Jones, a machine learning engineer running the fraud detection team at Zillow. They’d met at age 10 in London. “Declan farted on me during the entrance exam to our school,” said Deniz, explaining how they became friends.

As a history major at the University of California, Berkeley, Declan initially studied ancient languages. One day in cuneiform class, where Declan and his classmates translated the Law Code of Hammurabi, the professor congratulated them for being among the 800 people most knowledgeable in the ancient Akkadian language. “Cool,” thought Declan, but “What the f**k am I doing?” 

Declan’s language skills — logic and pattern matching — translated well into computer science, which became his second major and ticket to Zillow. He was looking for more meaningful work when Deniz’s email arrived. A left-leaning co-op house manager skeptical of capitalism, Declan had to do some “mental gymnastics” to talk himself into joining the startup. But the mission was right. He was in.  

Just before COVID froze the global economy in March 2020, the team applied to IndieBio. 

At that point, IndieBio had already funded three cell-based meat companies that were very successful, and wasn’t inclined to fund another – unless it was really different. What Deniz proposed was absolutely that. At the time, Po Bronson was a Partner at IndieBio, and Westley Dang (now a Principal and Program Director) had been on the job only a week. They knew they would be funding pure science risk. But they believed it could work, and if it did, it could be huge. 

It wasn’t until the beginning of September 2020, that Kent, Huisman, and Jones could join Po in the IndieBio basement. By then, Po had been made Managing Director of IndieBio and General Partner in SOSV. 

The building was quiet; most startups worked remotely due to the strict shutdown. Po had the opportunity to train the Prolific founders every single day, a little at a time. He taught them to think like VCs. In one memorable drill, Po created PowerPoint slides for made-up companies, including a levitation startup, and had Deniz pitch them on the spot. Po gets credit for naming the company Prolific Machines. According to Deniz, Bronson believed a startup should feel to investors like a cool party – and a company name should be able to double as the neon sign on a nightclub.

“It’s safe to say that had Po not existed, there is a good chance Prolific would not exist today,” says Deniz. 

For months, Deniz worked on the cells, Max built machines, and Declan turned it all into data. In January of 2021, after four months, their seminal experiment paid off – cells were growing fast without any growth factors at all. The team was ecstatic. The only problem was, they had spent all their capital pulling it off. They had to raise, and fast.

The company also had a classic problem: being copied. The team didn’t want its secret method to get out. How could they raise money without sharing the details? Po introduced them to five investors, to whom the Prolific team showed their data and cell images – without sharing their secret. From those five, they chose three to learn what made their machines so prolific. Two made offers.

One of those two was Arvind Gupta, a Partner at Mayfield and the founder of IndieBio. He was the world’s first VC in cultured meat. And he was immediately aware that Prolific’s machines could grow more than meat; they could grow cells that produce drugs for pharma companies, too – cheaper than anyone in the world. One night, Arvind invited the team to the garage at his house (COVID-19’s Delta variant had the world in shutdown again) to brainstorm target markets. Arvind saw how committed the team was to their climate mission. One week later, in the same open garage, Deniz and Arvind kneeled to the floor to sign the term sheet with a black Sharpie (much to the subsequent dismay of Deniz’s legal counsel who had not reviewed the term sheet). 

Prolific had set the record for fastest seed round in IndieBio history.

When Breakthrough Energy Ventures (BEV) led Prolific’s Series A six months later, (another IndieBio record,) the climate tech world took note. BEV was famous for not believing in the economics of cultured meat, and Prolific Machines changed their minds.

Solving this problem slowly is equivalent to not solving this problem at all.

Deniz Kent, Co-Founder and CEO, Prolific Machines

Prolific didn’t leave IndieBio for quite some time. They became the test case for a new way of building companies, not just startups, at IndieBio. They stayed another 11 months after their Series A, grew to a team of 28 people, and finally came out of stealth mode on the stage of the SALT conference in New York in September 2022. By then, the company had raised $42 million, and its investors also included David Adelman, Mark Cuban (owner of the Dallas Mavericks), The Kraft Group (owners of the New England Patriots), David Rubenstein, Michael Rubin, Breyer Capital, The SALT Fund, Purple Orange Ventures, Fred Blackford, Jake Poliskin, and Baruch Future Ventures. A number of celebrities and restaurateurs have also invested in Prolific including: Kevin Love, Tobias Harris, Meek Mill, Ciara and Russell Wilson, and Emily Ratajkowski.

Only then did Prolific Machines move across the Bay to their headquarters at the old Jelly Belly factory in Emeryville. 

The Prolific team is surprised at how much happened in three years. “If somebody had told me that entrepreneurship could look like this, it would have been higher on my list of things to do,” says Max. By “this,” meant Max, “You could get people to buy into this, collectively solve a hard problem, and get the brightest minds involved while not living on the edge of personal financial ruin all the time.”

Prolific is working against time, however. The UN now estimates that greenhouse gas emissions need to fall 60% by 2035 compared to 2019 levels to limit climate change to 1.5° C (and no, the world is not on track). “Solving this problem slowly is equivalent to not solving this problem at all,” says Deniz. 

With another funding round in the works, perhaps Prolific can upend animal agriculture quickly. Their unwitting partners will be the billions of people who love eating meat.