On the windowsill of a science laboratory high above the clamor of the Harvard Medical School campus, tidy rows of sunflower, avocado, and lemon plants bask in the afternoon sun.
Every day, scientists in this brightly lit lab take short breaks from their biological experiments to tend to the garden, hoping that one day the sight of thriving plants will bring comfort to their absent colleague, a young, Russian-born scientist who planted them from seedlings.
The plants belong to Kseniia Petrova, 31, a rising star in the burgeoning field of aging research who has been fighting a high-profile legal battle to return to a renowned laboratory where she and a team of scientists are exploring some of the most abiding mysteries of life: How precisely do organisms age? And is it possible to slow or even reverse the process?
Petrova’s future has hung in the balance since Feb. 16, when she allegedly failed to declare frog embryos that she was bringing back from France for research at Boston Logan International Airport, and then allegedly lied to customs authorities about the contents of her luggage. In response, federal authorities canceled Petrova’s visa, charged her criminally, and detained her for nearly four months in a barracks-style detention center in Louisiana where she was unable to communicate with her family in Moscow.
Those actions have sent chills through the scientific community at Harvard and in her home country of Russia, where her family and former research colleagues say they fear she will be persecuted for her past political activism.
“Every day it was like a horror,” said Petrova’s mother, Irina Petrova, from their home outside Moscow, in the family’s first public comments since her ordeal began. “Something is wrong with this world if such a thing is possible.”
Petrova was released from federal custody last month but remains essentially under house arrest — unable to work or travel outside the country — while she fights an uphill legal battle to prevent the Trump administration from deporting her to Russia, which she fled in 2022 after being arrested for protesting the war in Ukraine.
To many, both in the US and in Russia, Petrova’s case has come to symbolize President Trump’s hardline stance on immigration and his sharply expanded campaign against scientific research. It also represents a test of wills between an ambitious scientist and federal prosecutors who insist they are merely enforcing a law meant to protect Americans from dangerous biological specimens. She now faces three felony charges, including smuggling, which carries a maximum sentence of 20 years in prison.
“The rule of law does not have a carveout for educated individuals with pedigree,” US Attorney Leah B. Foley said in a video message.
Now, as her legal case drags into its sixth month, Petrova spends most of her days confined to a small apartment near Fenway Park, where she leads a hermit-like existence, reading biology textbooks and playing the guitar, her friends and lab partners say. She did not respond to multiple requests for an interview.
Inside the fifth-floor Harvard Medical School lab where she worked, Petrova’s prolonged absence is strongly felt.
Her colleagues described Petrova as a “super nerd,” who once dressed up as a dead cell for Halloween and is so committed to her research that she sometimes collapsed on a couch after working through the night.
A specialist in bioinformatics, a field that uses computer tools and statistics to analyze large sets of biological data, Petrova was a core member of a team working to turn back the clock on aging cells and develop treatments for age-related diseases.
The laboratory, named after its founder and director, Marc Kirschner, built its own laser-based microscope that generates remarkably high-quality images of tissue samples. Researchers at the lab use the microscope to distinguish between healthy organs and unhealthy ones and to investigate how cells rejuvenate. What the laboratory needed, Kirschner said, was someone with Petrova’s computational skills to analyze the vast amounts of data generated by the microscope.
Petrova proved to be a quick and versatile learner, immersing herself not only in bioinformatics but also in experiments involving tissue samples, despite having little background in biology, Kirschner said.
“She really wanted to be a full scientist, which I fully agree with,” Kirschner said.
Like much of biology, the Kirschner laboratory is fixated on frogs — it even has a giant tank known as the “frog palace” — because the amphibians share many of the same genes and biological processes as humans. The goal was to develop a comprehensive map of embryonic frog cells, which the researchers hoped would be useful for scientists worldwide.
Petrova’s determination to pursue her interest in the natural world began early in life and was nurtured by her scientific-minded parents.
She grew up in Moscow as the second child of two engineers. Her father, Dmitry Petrov, is a computer engineer and her mother, Irina, a specialist in radio antennas.
Speaking from their summer home in Kuchino, a village in a forested area west of Moscow, Petrova’s parents described their daughter as an adventurous, free-spirited girl and gifted musician. Photos and videos shared by her family show her playing the flute and singing Ella Fitzgerald’s “Summertime” in a soulful voice, while her father strummed the guitar. In another photo, as a very young girl, Petrova is seen carrying a log nearly twice her size through the forest near Kuchino.
The family’s log cabin-style summer home in the forest was a refuge for Petrova to nurture her creativity, her parents said. Friends and scientists would gather at their home in the woods, often discussing books and playing music until late at night, her parents said. Sometimes she was so immersed in her studies that she would bring her laptop or book outside and read on a tree stump while her family foraged for mushrooms or berries, recalled Vladimir Mazin, a scientist and longtime family friend.
In a sign of her early resolve, Petrova decided at age 13 that she would transfer from a focus on English studies to biology and chemistry. She completed the paperwork herself and switched programs without consulting her parents.
“Kseniia was a very determined child. She would make a decision and stand by it at a very early age,” Mazin said.
Petrova’s interest in politics long preceded the invasion of Ukraine, her parents said. In 2011, while she was still a teenager, Petrova and her older brother became official election workers on a commission tasked with certifying the local results of Russia’s parliamentary election. The 2011 election was marred by widespread reports of fraud and is now seen as a turning point, exposing deep cracks in Russia’s democracy.
Then, on the day after Russia invaded Ukraine in February 2022, Petrova and her friends joined protesters on the streets of Moscow. Several days later, Petrova protested again and was arrested, charged with an administrative offense, and released, her parents said. That incident, her parents said, made it difficult for her to find a job in scientific research in Russia and contributed to her decision to leave the country for a job at Harvard.
Her Facebook page still contains several postings that are critical of Russian leader Vladimir Putin, including one calling for his impeachment after the invasion of Ukraine.
After graduating in 2022 from the prestigious Moscow Institute of Physics and Technology, Petrova was recruited for an ambitious project to sequence the entire genomes of 100,000 people in Russia, an important step to identifying and treating hereditary diseases.
But Konstantin Severinov, a prominent molecular biologist from Moscow who headed up the initiative, said Petrova’s political views presented immediate problems. A hiring official for the project suggested that she rethink her outspoken support of the opposition movement to Putin so she could get through the security clearance process, Severinov said. When she refused, Severinov brought Petrova on as a consultant rather than an employee.
“I would say it was partly naivete, but it was also about her being a principled person,” Severinov said. “There’s an irony to the fact that Kseniia is someone who suffered here [in Russia] because of her political views, and now she’s suffering where she’s presumably on the good side. It turns out this is all like [the novel] ‘1984.’”
Petrova’s family and colleagues are now worried for her future, which looks precarious, given the nature of her alleged offense and her history of political activism in Russia.
After stopping Petrova, a federal customs officer at Logan reviewed her phone and uncovered a series of text messages suggesting Petrova knew she was supposed to declare biological material when entering the United States — and then misled authorities, according to a criminal complaint. In one text, a laboratory supervisor asked Petrova about her plan for getting the embryos through customs, noting that it was “the most delicate part of the trajectory.”
While sitting on the tarmac, Petrova fired back in a text, “No plan yet. I won’t be able to swallow them,” according to the criminal complaint.
When Petrova was questioned by the customs official, she denied carrying any biological material in her luggage and said she didn’t know she was supposed to declare the frog embryos, prosecutors allege.
Yet Petrova’s attorneys maintain there was no legal basis for detaining and charging her, arguing the frog eggs in her luggage were not biological material as classified under federal law. The eggs were immersed in formaldehyde, which rendered them nonliving and nonhazardous, they maintain. As such, they were no different from shoes or paper, which do not have to be declared at customs. In recent court testimony, the US Immigration and Customs Enforcement agent who wrote the criminal affidavit against Petrova admitted that he was unable to explain the meaning of biological material.
In interviews, four immigration law experts told The Boston Globe that, while the smuggling charge against Petrova is unlikely to survive legal scrutiny, courts typically give federal agencies broad discretion over immigration matters. It is extremely rare for federal judges to reinstate visas once they have been revoked, because they tend to view those decisions as matters of foreign security and outside their jurisdiction, immigration law experts said.
Yet if she is deported back to Russia, several immigration experts said, it is highly likely she would be arrested and imprisoned for her outspoken opposition to Putin’s policies.
“There is no worse place that [Petrova] could go than Russia,” said Harold Hongju Koh, a professor of international law at Yale Law School. “Putin will have no hesitation at all about locking her up for criticizing his policies.”
Inside his lab office, decorated with framed images of frogs, Kirschner looked crestfallen as he discussed the loss of one of his star researchers. He recalled how, decades ago, he brought intact live frogs from Switzerland through US customs at an airport with little hassle.
“I definitely feel emotional about this,” Kirschner said. “It makes me realize that, with all these changes, that we’re moving toward more of a police state.”
Petrova’s parents said they talk to their daughter via video feed two or three times a week, and remain anxious about her fate if she is deported to Russia. “We have brutal repressions in this country,” said her father, looking downcast. “We don’t know if they will forget about [Kseniia] or they will brutally put her to trial.” He added, “In Russia, authorities act as they wish.”
On June 12, Petrova was released from ICE custody, emerging from the front doors of the Boston courthouse wearing a T-shirt that said “Hakuna matata,” or “no worries.”
Since then, Petrova has taken up several new hobbies, her parents and friends said, including wood etching and baking bread.
She’s also planted more vegetable seeds, which have begun to sprout around her apartment.
Chris Serres can be reached at chris.serres@globe.com. Follow him @ChrisSerres.