Every six months, Dr. Bridgette “Jeanne” Billioux gets on a plane to Liberia to study a group of Ebola survivors suffering from headaches, seizures, and memory loss. She’s a clinical fellow at the National Institutes of Health, and is trying to figure out if many Ebola deaths could be tied to neurological complications.

It’s hard work in a country that doesn’t have tools like MRIs and CT scanners, where people present with many unrelated health issues, and where doing a spinal tap might mean exposure to infected fluids. But when her mentor, Dr. Avindra Nath, asked for volunteers to study these survivors and provide them medical care, Billioux didn’t hesitate to raise her hand.

The Louisiana native first became interested in medicine at age 12, after her grandfather was diagnosed with dementia. She chose neurology as her speciality.

“When I saw strokes and seizures in real life, putting the exam together like a puzzle to figure out where the deficits are in the brain, it utterly gripped me,” she said.

Many of her Liberian patients have slowly improved — now she plans to bring some to the NIH for further study. Beyond that, she’s trying to plan a neurology clinic to help train Liberian medical students, since the nation has a dire need of neurologists. “It doesn’t matter how smart students are, if they don’t get exposed to neuroscience, if they don’t get interested,” she said.

— Max Blau

Dr. Andrew Boozary might be the wonkiest of the Wunderkinds. The Canadian doctor, a family medicine resident at St. Michael's Hospital in Toronto, has already influenced the intersection of health and policy, from founding the Harvard Public Health Review to advising one of Canada’s top health officials. But his latest focus — fighting to improve health care for marginalized populations — hits closer to home.

This summer he traveled to Yellowknife, the capital of the Northwest Territories, where he saw low-income palliative care patients who had no electricity or water. In a country known for socialized medicine, it made him think about who still lacks access to proper treatment.

Boozary is the son of an Iranian doctor who fled to Canada after being tortured during the revolution. He wants to fix disparities in a health system that benefitted his family when he was young — but whose complexity has, at times, failed those who need it most now.

“There may be no more effective individual in the country coming up as a health services researcher who is squarely at the impingement of policy and science,” said the man he advised, Eric Hoskins, Ontario’s minister of health and long-term care.

Thus, Boozary’s next goal is to open a health research shop that focuses on the ways poverty impacts health policy in Canada. “I hope data will inform my advocacy,” he said. “I want to be a scientist first — but where you see inequities, you need to be an advocate. I don’t think they’re separate."

— Max Blau

When the Zika outbreak in Brazil started making headlines, Bin Cao and his colleagues knew they were prepared to study the then poorly-understood virus. Cao, a postdoc at Washington University in St. Louis, researches bacterial and viral infections during pregnancy.

“We had all the tools to study the infection during pregnancy,” said Cao.

Cao and his colleagues were able to develop an animal model of in utero infection to show that Zika was indeed a pathogen that could compromise the placenta’s defenses. They’ve also researched exactly which cellular and molecular mechanisms Zika uses to get across the placental barrier and then to infect fetal cells. And they’ve started to look at potential means of blocking the virus.

“Zika has the ability to compromise or subvert some cellular defense mechanisms in the placenta,” Cao said. “There are a lot of open questions about why Zika is different from other pathogens.”

Cao, who is from China and did his Ph.D. there, said he has had a longtime interest in developmental biology.

“The early stage of life has always fascinated me,” he said.

— Andrew Joseph

The two big ideas Ying Kai Chan is tackling in science — reducing the harmful side effects of gene therapy and developing better vaccines to protect against viruses — might seem wildly different from one another. But they’re actually connected by a common goal: getting the immune system to respond to a pathogen in just the right way.

Chan’s interest in immunology began during his childhood in Singapore, which was frequently hit by dengue virus outbreaks. In his Ph.D. research at Harvard Medical School, Chan engineered dengue virus so that instead of proliferating without being detected by the immune system, it would instead trigger a robust immune response.

“In the case of the vaccine if you can disarm the virus, you can make a safe, attenuated vaccine,” Chan said. "On the flip side, if you use a virus to deliver gene therapy, you don’t want it to have any immune response.”

That’s now Chan’s goal as a postdoctoral researcher in George Church’s lab at Harvard Medical School, where he’s created an “invisibility cloak” that shields gene therapy and its viral carrier from the immune system. The cloak blocks the immune receptor that normally recognizes the virus, called adeno-associated virus. And while he’s been testing the technology in human cells and mouse models, he’s also been bouncing ideas off the other scientists he meets in his volleyball league. He offers them thoughts on their research, too.

— Megan Thielking

Dr. Hsiao-Tuan Chao focuses her work on the rarest of rare diseases: genetic neurodegenerative disorders that impact just a handful of children around the world.

She’s conducting her postdoc at the Baylor College of Medicine, focusing on Rett syndrome, which predominantly affects young girls.

“When you’re talking about childhood neurological disease, it’s a situation where it’s just a quirk of fate — something small happens that leaves you facing a lifelong challenge,” Chao said.

So she's working to unravel how small genetic changes can impact how the brain is wired — specifically, how different neurons talk to each other — and in turn influence how we think and communicate.

“It’s devastating: Imagine you have a healthy child who does everything a baby is expected to do, walking and talking — then inexplicably begins to lose all of this,” she said. “It’s heartbreaking.”

Her team has unraveled the genetic cause for the disease and has some idea of how it functions, but they don’t fully understand the intricacies. That's the next challenge.

For now, she's focused on recovery — her Houston home was deluged during Hurricane Harvey, and she and her husband, also a scientist, scrambled to save lab materials. After that, she turned her attention to the tropical sugar apples and dragon fruit that she has delicately tended to over the years.

The plants, she said, made it.

— Meghana Keshavan

Dr. Salil Garg has an odd inspiration for powering through when his lab work isn’t going well: He draws on his many years as a Cincinnati Bengals fan.

“It’s character building, it really is,” said Garg, a molecular pathologist at Massachusetts General Hospital and a postdoc at MIT’s Koch Institute for Integrative Cancer Research.

“It prepares you for research, because like 90 percent of the experiments you do don’t work,” he continued. “The inverse of that is the success rate of the Bengals, so it matches up pretty well.”

As a physician, Garg examines cancer cells for genetic changes that can help him identify treatment strategies. But Garg, who is starting his own lab at the Koch Institute next year, spends his research hours studying cancers that don’t have many of those mutations.

He’s interested in the heterogeneity seen in some tumors — specifically, when cells respond to treatments differently even though they share the same DNA. Those differences could help explain why some cancers recur after treatment. He’s focusing first on the role of microRNAs, which regulate gene expression, in pediatric brain cancers and some forms of leukemia.

Garg, a father of two, often feels like he doesn’t have enough time to devote to his dual careers as a researcher and physician. But he loves filling both roles. “It really lets you see the where the real problems in therapy are, and where the real places we need to do better are,” he said.

— Andrew Joseph

Anubhuti Goel is part teacher, part neuroscientist. Her postdoctoral research focuses on the defective circuits in the brain that could contribute to autism and other intellectual disabilities. And to do that, she has to teach mice.

Goel, raised in Bangalore, India, has focused in particular on Fragile X syndrome, a genetic disorder that can occur along with autism and is thought to be the genetic cause of autism in patients with Fragile X syndrome. Goel’s work initially involved training mice to recognize different visual stimuli, and then tweaking those stimuli slightly to see how the mice adapt. The healthy control mice take three or four sessions; the mice engineered to mimic Fragile X syndrome can take nearly twice as long.

She likens it to a morning commute, disrupted.

“If they’re used to following a certain route to work and they have to change it, they’re not flexible enough to make that change,” she said. Goel discovered that there’s a specific group of inhibitory cells in the brain malfunctioning in the Fragile X model. Inhibitory cells keep the brain’s excitatory cells in check. That, Goel said, mirrors the hyperexcitability seen in some individuals with the syndrome.

“If the [brain’s] balance is disrupted because of this dysfunctional group of cells, it’s not surprising you have those symptoms,” she said. Now, she’s working to translate that discovery to test her findings in humans. She’s hoping to take her research and set up her own, independent lab in the coming year.

— Megan Thielking

As you get older, your risk of developing cancer increases. That might seem obvious, but Ana Gomes wants to know why. She’s studying a chemical, found more prominently in older people than young, and how it may be thwarting breast and lung metastases in mice.

And she’s had to figure it all out, from the gene on up.

Gomes, a postdoc at Weill Cornell Medicine, is scouring the blood plasma of healthy people young and old, looking for chemicals abundant in the elderly and spare in the young. So far, she’s found a promising one that looks like a cellular waste product. She’s dumped it in a dish with cancer cells, and watched those cells grow much more quickly than normal.

She thinks there might be something more prominent in the blood of elderly people that accelerates tumor growth and that a possible target for treatment would be that chemical: reduce its levels, and possibly slow cancer growth.

But there has been just one problem: Since the chemical is a metabolite, she’s needed to figure out where it comes from, trace it back to the enzyme that makes it, and then to the gene that makes that enzyme.

“I think that’s probably the most challenging thing, not knowing anything and having to build everything from the ground,” Gomes said. “But it’s also what makes it fun, right?”

— Ike Swetlitz

The first rule of being a disease detective: Don’t get sick from what you’re investigating. This was on Dr. Victoria Hall’s mind when the Centers for Disease Control and Prevention called her into action this past Easter Sunday. The assignment: find out how measles was spreading among a community of Somali refugees in Minnesota.

Hall is one of about 150 postgraduate fellows at the CDC working as epidemic intelligence service officer. Based in the Twin Cities, she was among the first to respond to recent outbreaks of tuberculosis, Seoul virus, and other infectious diseases. Her job is to help trace the origins of the outbreak, share information with civic leaders, and draw up prevention strategies that respond to each community’s unique needs. That can include rebutting myths, such as the dangerous canard that the measles vaccine causes autism.

“It’s easier for fear to take hold than science,” Hall said.

Raised in Cincinnati, Hall studied to be a veterinarian, only to realize that she’s also adept at working with people, especially communities that may be wary of government health initiatives. So devoted to her calling that she named her cat Ella (short for salmonella), Hall hopes to keep working for the CDC after her fellowship. As she well knows, convincing people to choose fact over fear can be a matter of life and death. She’s up for the challenge — so long as she doesn’t break the first rule for disease detectives.

— Max Blau

Many people think stopping malaria means stopping mosquitoes, but Jiang He thinks to beat this disease, you have to go to the human liver. The MIT postdoc is studying this vital organ and how the malaria parasite thrives in it to look for drugs that can stop the disease from taking hold.

He’s found a few gene variations that might impact liver function, and is investigating how they affect susceptibility to a disease that infects up to 600 million people per year.

He grew up in a small village in the Hunan province of China. The son of two rice farmers was enchanted early by the role of medicine in health. Before embarking on a career in research, he spent a winter break from college trying to educate villagers along Poyang Lake in Jiangxi province on how to stop the spread of bird flu. It was 2006, at the height of the epidemic.

“Some of the farmers, around that time, they were not aware of the dangers of the virus,” he said. “They sometimes will kill the sick animal and then eat the meat.”

In the lab, he’s learned that malaria is wily. Different strains attack the body in different ways, meaning that discoveries about the parasite often end up being strain-specific, rather than to the disease in general.

“There are a lot of surprises,” he told STAT. “That really makes the … whole process of eradicating malaria way more challenging.”

— Ike Swetlitz

What prompted Angela Jablonski to pursue a career in neuroscience was watching her parents die at a young age. In her third year of a three-year fellowship at Merck Research Laboratories, she’s working on a neurodegenerative disease — Alzheimer’s disease — and looking at how immunotherapy may be able to treat it.

Her team is developing an antibody that targets an Alzheimer’s gene variant called APOE4, found in about 1 in 5 people and that increases their odds of developing the condition. What they are finding pre-clinically: If they administer the APOE4 antibody to cultured neurons, toxic brain tangles that are a hallmark of Alzheimer’s seem to get smaller.

Jablonski has a second passion: She teaches science writing to students at University of Pennsylvania, where she earned her Ph.D. The program, called PennPREP, is geared toward postbaccalaureate students there, in hopes to help encourage their interest in advanced study in the sciences.

She grew up in rural Pennsylvania, where her mother also dealt with chronic health issues and little access to consistent health care. Her parents supported her, she said, but she didn’t have a scientist mentor to learn from. She’s trying to change that for the next generation of young Pennsylvanians.

“If you’re underrepresented in the sciences, it’s hard to be open and honest about who you are and where you came from,” Jablonski said. “Another goal of mine: I try to help them to be comfortable with their identity.”

— Meghana Keshavan

Harmut Jahns is an organic chemist who likes to tinker with RNA.

As a postdoc at Alnylam, he's been looking at how chemical modifications on a class of RNAs called small interfering RNAs can make them better drugs. In particular, he's found that certain changes to siRNAs make them more effective, potentially lowering the dose needed to treat an illness and reducing side effects.

On top of that, Jahns has been building his own siRNAs, creating new structures that allow researchers to see how they interact with proteins that help them stay stable. This was a side project, he said, that ended up taking over his brain.

"When I have an idea in my mind, I cannot stop thinking about it," he said. "I work on weekends and nights."

Jahns fell into medicinal chemistry early in his academic career, after seeing how small molecules could affect biological systems. In his time at Alnylam, he's enjoyed collaborating and sharing, and looks forward to his next opportunity.

In the meantime though, he said, he'll head to the water. Jahns is avid sailor, having joined clubs and raced boats in Boston. He likens sailing to science.

"Science is somehow like being on a sailboat ... you want to go somewhere, you don't know exactly where you go, you don't know how it looks, but that's where the discovery comes in."

— Meghana Keshavan

Bianca Jones Marlin is fascinated with familial bonding: Her own parents fostered several kids through the course of her childhood, and from a young age Marlin got a firsthand look at how families can form.

Though she began her career as an AP biology teacher, Marlin quickly pivoted and pursued a Ph.D. at New York University. These days, she’s completing a postdoc at Columbia University in neuroscience.

Her doctoral work showed that virgin female mice will cannibalize crying pups, whereas mothers who have given birth will comfort any young. The reason? A surge of the hormone oxytocin floods a female’s body as she gives birth — and that inexorably changes her brain chemistry. Marlin found that when she injected oxytocin into the brains of virgin mice while playing a recording of crying pups, they’d suddenly behave in a far more maternal manner.

Marlin has dedicated her postdoctoral study to epigenetics — specifically, learning how grandparents can pass on residues of their past experiences to their descendants.

“If your parents face trauma, or you do and you’re pregnant — certain things can be passed through to the fetus that can affect the fetus inside you,” Marlin said. “But if your grandchildren have that effect, that means something else is being carried through.”

Her dedication to neuroscience doesn't stop in the lab. At home, with her own family, is Santiago Ramon Y Cajal, her cat named after the famous neuroanatomist.

— Meghana Keshavan

Her experiment is simple, but it has the potential to radically change the way companies think about developing drugs.

Xue Liang puts human feces and an experimental small molecule together in a test tube. She incubates them for a few hours. Then she measures how the drug metabolizes.

The idea: to see how the enzymes expressed by the bacteria inside our gut influence how well the drug works, or how safe it is. If she can understand that, she explained, then maybe she can find paths “to improve the efficacy of future drugs and also to minimize or to reduce [their] side effects.”

Liang is a microbiome scientist at Merck’s new research site in Cambridge, Mass. She joined the company a year ago, after completing her Ph.D. in pharmacology and spending one year as a postdoc, both at the University of Pennsylvania.

Liang’s work at Merck grew out of a study she conducted while working on her Ph.D. She and her collaborators found that gut bacteria impact the effectiveness of indomethacin, an anti-inflammatory drug used to treat pain and arthritis. She’s now studying the same process in experimental drugs for cancer and infectious disease.

Liang, who grew up in China and practices Chinese calligraphy in her spare time, said she’s driven a keen sense of curiosity and a desire to make contributions that may someday help extend lives. And she’s something of a pioneer: Although interest in the microbiome is booming, Liang estimates that just a handful of labs in the U.S. study the interactions she’s investigating.

— Rebecca Robbins

Shane Liddelow says he has muggers to thank for his life — and his scientific career.

As a college student, Liddelow was robbed and suffered a concussion. He went to the hospital — where doctors discovered and repaired an unrelated aneurysm that he said could have killed him if it had gone undetected. While on the surgical bed, he found himself fascinated by the image of his brain on the monitor — setting him down the path to becoming a neuroscientist.

Liddelow went on to get his Ph.D. in pharmacology at the University of Melbourne in Australia. Now, he’s a postdoc at Stanford studying the activation of astrocytes, the star-shaped cells that are more abundant than any other cell type in the brain.

These activated cells are known for supporting neurons, but Liddelow and his collaborators showed in a study published in January that they can also be destructive. Their data from cell culture, mice, and rats demonstrated that the brain’s immune cells can release signals that spur the activated astrocytes to destroy neurons.

The implication: They might play a role in neurodegenerative disease. And they might be good targets for drugs.

Come February, Liddelow will open his own lab at New York University, where he’ll continue studying astrocytes.

Liddelow, who grew up in a town of 4,000 on the western coast of Australia, doesn’t try to downplay his enthusiasm for science.

“I like to spend my nights and weekends looking at data,” Liddelow says. “It makes it sound a little pathetic now that I say it out loud — but there's just too much stuff to know and very little time to know it.”

— Rebecca Robbins

Maciej Maselko can make yeast cells explode. But it’s more than a cool party trick — the University of Minnesota postdoc may have come up with a tool to make sure that genetic modifications we make in plants and animals don’t spread into the wild.

Maselko imagines that bioengineers could create corn that makes pharmaceuticals, or fish that eat up pollution in a lake. Scientists might want those populations to be able to sustain themselves, but not spread their altered genes to wild populations.

To do this, Maselko has devised a creative CRISPR-Cas9 trick. Instead of snipping out a part of a gene and replacing it with something different, Maselko’s cellular machinery leaves the genes as they are, but puts them into overdrive. Remember the exploding yeast? They blow up because Maselko’s technology instructs the cell to generate an immense amount of proteins caused by that particular gene — but only when the engineered yeast mate with wild versions.

Maselko has an affinity for the wild — he spent much of his childhood in Anchorage and tries to get out of Minneapolis at least once a week, often to the north shore of Lake Superior. But fascinated as he is by the natural world, he also appreciates the ability of humans to control it.

“There’s a lot of these really cool things we’re starting to be able to do with synthetic biology,” Maselko said. “But we really need to be able to have a good way of containing a lot of these genes.”

— Ike Swetlitz

When Katherine Miller was in graduate school, she studied genetics, the hot field at the time. Now as a postdoc, the hot field is bioinformatics. Her new focus combines them both.

A postdoc at Nationwide Children’s Hospital in Columbus, Ohio, Miller is working with colleagues to develop CardioGenomics eXchange commons, or CGX. It’s a space for researchers to share genome sequences and discuss their findings. The goal: to boost understanding of the genetic variants that contribute to heart disease.

Miller and colleagues have also developed software that can identify the variants that merit further exploration.

While the project is now focused on heart disease, Miller sees broader uses. “This type of genome sequencing and precision medicine can really be targeted to any area,” she said.

Miller said she enjoys the collaborative nature of the bioinformatics work as opposed to the often solitary job of running experiments in a genetics lab. But she hopes to keep using both skills as her career advances.

Miller, who coaches a middle school softball team and still plays herself, said she always had an interest in science — because it was a field that could make a difference.

“It felt meaningful, and that was always important to me,” she said.

— Andrew Joseph

Some scientists agonize endlessly about planning their experiments. Not Leslie Mitchell.

“I’m a little bit fearless in the lab in terms of thinking up an idea and diving in and trying it,” the New York University postdoc said.

That fearlessness served Mitchell well as a key architect in an international effort to synthesize the yeast genome, an important step towards the creation of synthetic life. Mitchell was the lead author of one of seven papers published in March announcing the project’s latest milestone: the completion of another five of yeast’s 16 chromosomes. Mitchell also played a crucial role in designing the project as a whole and mentoring collaborators.

A native Canadian with a passion for public outreach, Mitchell did her Ph.D. in systems biology at the University of Ottawa. She started her postdoc at Johns Hopkins and followed Jef Boeke, the geneticist leading the synthetic yeast chromosome project, when he moved his lab to NYU.

Mitchell has begun to split her time between her postdoc and Neochromosome, a startup she co-founded with Boeke and two others. The company’s focus: to find commercial applications for the technology deployed in the synthetic yeast project. It’s still early, but the company could eventually try to build cells that would produce a drug or that would themselves be a therapy, Mitchell said.

She’s planning to transition to a full-time role as chief science officer at Neochromosome in the coming months.

“There are very few aspects of this project,” she said, “that don’t get me excited.”

— Rebecca Robbins

Michael Mitchell is trying to ferry drugs to a challenging part of the body: bone marrow. The organ — which creates red blood cells, white blood cells and platelets — is under-researched in the fields of drug delivery and gene therapy. In part, that's because it’s so hard to track the vehicles carrying gene therapies.

Plus, said Mitchell, what works in cell experiments doesn’t always work in animal models.

“Where we begin to have a disconnect is that we make our decisions [on potential treatments to test] very early on in vitro, but those settings don’t recapitulate what would work the best in vivo,” he said.

That tracking problem is where Mitchell’s work as a postdoc researcher in Bob Langer’s Koch Institute lab comes in. He’s harnessed DNA barcoding technology that allows scientists to tag hundreds of potential delivery materials, get them into animal models, and then track them see where they traveled and how well they worked. The platform serves as a potential way to help researchers quickly discover new carriers for a broad range of treatments, from small molecules to gene therapies.

An East Coast native, Mitchell finds time away from the bench to stay on top of sports. “Unfortunately, I’m a diehard Yankees fan,” he said. He’ll make the move to Pennsylvania next summer, where he’s accepted a position as a professor and principal investigator at the University of Pennsylvania. His new lab will focus on developing different types of nucleic acid delivery platforms for gene therapies.

— Megan Thielking

David Nelles once chased a trash truck to a dump the size of a football field to retrieve a lab notebook accidentally tossed away.

It’s that tenacity — and maybe sense of adventure — that guides his work in understanding how RNA might work therapeutically.

“RNA is really cool, because from an engineer’s standpoint it provides an extremely information-rich yield for what’s going on inside of a cell,” Nelles said.

These days, he is CRISPRing RNA as a postdoctoral fellow at the University of California, San Diego, and is applying the same principals to therapeutics development at San Diego biotech startup Locana, of which he’s co-founder and CTO.

The biotech world is avidly exploring the potency of gene therapy, and Nelles figures that RNA therapies might offer similar potential. His work in the Yeo lab at UCSD showed early promise in using engineered RNA molecules to treat a number of neuromuscular diseases — such as amyotrophic lateral sclerosis, Huntington disease, and a number of ataxias. That’s because they’re all caused by a repetitive class of RNA, he said — and it’s actually possible to eliminate disease-causing RNA very efficiently, he said.

“Both the CRISPR field, and the Swiss army knife that is Cas9, have really influenced my efforts,” Nelles says.

As for the notebook, he said, his brother came along for the ride, and he figured out within a 20-foot radius where the notebook could be.

He found it, and the only damage, he said? It smelled.

— Meghana Keshavan

Halley Oyer’s career origin story has a precise launching pad.

When she was 6, her neighbor threw out a collection of old textbooks; Oyer found a dated biology tome and took it home. Even now, 20-something years later, she remembers looking at the diagrams that explained things like how dysentery spreads.

“It was the way the world worked,” Oyer said. “I wanted to help chip away a little bit at that understanding.”

Oyer is now a postdoc at Drexel University studying Sigma 1, a so-called “chaperone protein” that influences other proteins and pathways involved in the amount of stress cells endure. Cancer cells tend to be under greater stress than healthy cells, so Oyer and her colleagues are investigating whether manipulating Sigma 1 can launch a downstream effect that cripples those cells’ stress response. If the cancer cells can’t alleviate the level of stress they’re under, they’ll die.

Sigma 1 has long been explored as a therapeutic target, but even after years of study, researchers still aren’t sure exactly how it influences other proteins and pathways.

Still, Oyer’s research has been spun out into a company, Context Therapeutics, where she works as a research scientist in addition to holding her postdoc position. She hopes to join the company full time when she wraps up her fellowship.

Outside the lab, she spends her time cooking, gardening, and baking. “It’s just like chemistry and biology, but on the home scale,” she said.

— Andrew Joseph

Dr. Anca Pasca isn’t satisfied when babies born preterm simply survive.

She’s on a mission to make sure they thrive, too.

Pasca, a neonatology fellow at Stanford, said she “couldn’t make peace with” the fact that about three-quarters of premature babies have lifelong neurodevelopmental problems, such as cognitive impairment, cerebral palsy, and autism.

So she set out to develop a better way of studying the extremely premature brain — and came up with a method she and her collaborators demonstrated in a 2015 paper. In the lab, she coaxed skin cells into becoming induced pluripotent stem cells, or iPS cells. She then steered those immature cells into becoming the kind of cells found in the developing brain of a baby with a gestational age of 22 to 24 weeks, around the threshold of viability.

“What I have now,” Pasca says, “is an extremely preterm human brain in a dish.”

She’s now using that model to study how insufficient oxygen, common in premature babies, harms the developing brain — and how to prevent that damage. She hopes to publish her findings next year.

Pasca grew up and went to medical school in Romania before coming to Stanford for her residency in 2010.

Medical resources were limited in Romania, so Pasca learned a style of medicine light on extra testing and heavy on use of existing clinical data — training that she thinks helps make her a better doctor in the U.S.

— Rebecca Robbins

Max Salick spends his days building little mini-chunks of brain to study disease.

He’s always been a builder, from a Lego factory he constructed at age 5 to the cerebral organoids he puts together as a postdoc at Novartis. From these engineered bits of brain, he learned about how Zika virus attacks the brain, but, he’s more excited about a more obscure disease — tuberous sclerosis.

It’s difficult to gather brain tissue samples from humans, so studying diseases like tuberous sclerosis is maddening, he said. But with organoids, Salick can afflict as many as he wants with tuberous sclerosis, giving him an unlimited number of ways to study what causes the disease.

Some of them he flash-freezes and then slices razor-thin so that he can see how the brain tissue develops. Others he dissolves in a papaya enzyme to sequence their genomes for genetic studies. The goal is to understand why tuberous sclerosis causes epilepsy, which would help scientists develop drugs to treat the disease.

“I have this thing for really complicated, difficult, just annoyingly complicated things,” he said.

But not necessarily at home. When he’s not in lab, he’s playing with Coda, a 9-year-old mix of border collie and German shepherd, who is so adorable that he got a citation from the Boston police “for being such a good boy,” as Salick described it. He has a picture of the violation envelope on his phone. It was filled with dog treats.

— Ike Swetlitz

Arun Sharma grew up in Huntsville, Ala., which is home to a NASA center. It helped instill in him an interest in science and space.

So it felt a bit like coming full circle when, as a graduate student, he was involved in a project that sent heart cells into space. The aim: learn how changes in gravity levels affect the heart not just as an organ, but on the cellular level.

Sharma also worked with cardiomyocytes derived from induced pluripotent stem cells to create a system that can test the side effects of various drugs. Because the cardiomyocytes act like the patient’s own heart cells, the testing is highly personalized.

“Until now, we haven’t had a great model system to study that off-target damage,” Sharma said. “But we now have a system, a really good personalized system, to screen for cardiotoxic effects.”

Much of that work was done while Sharma was a graduate student at Stanford. Now a postdoc at Harvard Medical School, he plans to use the genome-editing tool CRISPR to incorporate various mutations into the cardiomyocytes to see how those variants might contribute to heart disease at the cellular level.

“There’s a lot to understand at the basic science level” with this system, said Sharma. “But a big reason I like working with these cells is because I can see the translational aspects.”

— Andrew Joseph

For Elenoe “Crew” Smith, studying sickle cell disease is personal.

The research scientist at Vertex counts several family members and friends in her community in the U.S. Virgin Islands among those with the painful illness, in which misshapen blood cells can’t carry oxygen well enough to fuel the body and get caught in the body’s organs, causing damage.

“When I left the Virgin Islands for college,” she said, “my essay said, ‘I want to cure sickle cell disease.’”

What her collegiate self thought was a straightforward scientific task — how to reverse a genetic disease with uncomplicated inheritance patterns and a known mutation, turned out to be more challenging. After graduate school and a postdoc, Smith assumed she was heading into an academic career. But after learning about Vertex's sickle cell program, she decided to to join.

At Vertex, she’s testing different small molecules in the hopes of finding candidates that prevent blood cells from sickling. The goal is to stop the morbidity and mortality that comes from misshapen blood cells. She’s also part of a collaboration with CRISPR Therapeutics.

While living in cold climates for many years, Smith said her nickname is a testament to a year-round pastime in the Caribbean. Her father, who is from the British Virgin Islands, is a long-time sailor. After Smith’s birth, friends and family congratulated him on adding another member to his ship’s crew.

— Megha Satyanarayana

Fair skin. Family history. Runs outside. Dan Webster knows his wife is at risk of someday contracting melanoma. That’s why the researcher started taking annual photos of her moles back when he was a Stanford graduate student working in a genomics lab.

Webster soon realized it would be a “logistical nightmare” to catalog the photos. So he built an app to do it. Mole Mapper caught the eye of folks at Apple, who developed it for its ResearchKit, which lets users generate data for medical research. Nearly 3,000 volunteers joined the study — which became the focus of Webster’s postdoc work with the National Cancer Institute’s Center for Cancer Research.

The Mole Mapper data was published last February in Nature. The paper, Webster said, shows the power of collecting clinical data through apps. “I thought digital health and genomics would be integrated maybe in 20 years,” he said. “It happened in three.”

A native of Libertyville, Ill., Webster first grew enamored with science when he read about the Human Genome Project. “Before, all I’d known about DNA came from ‘Jurassic Park,’” he said. He recently landed a gig with Sage Bionetworks, a Seattle nonprofit that’s rolling out apps for the National Institute of Health. Moving forward, his eyes will be glued to the intersection of digital technology and genomics. It’s here where Webster believes he could someday help people — including his wife — identify skin cancer before it’s too late.

— Max Blau