For nearly a decade, Aryeh Batt had to hear that he was chasing an impossible idea. The possibility of growing human cells, printing functional tissue from them, and transplanting it into a human body sounded to many like a plot from a futuristic film. Even some of the doctors and colleagues he met did not hide their skepticism. There were those who called him, according to him, "Crazy Aryeh."
Today, after corneal implants produced in the laboratories of the company he founded have already been transplanted into five patients at Rambam Health Care Campus, Batt feels he has received the proof he was waiting for.
"People said it was impossible, that it was science fiction," he says in a conversation with Walla Health. "So we proved that it is no longer science fiction. There are people who couldn't see, and today they see thanks to this technology. It is no longer a dream or a presentation for investors. We proved that it is possible to manufacture tissue on a production line, test it, transplant it into a human, and that it can work."
The patient who regained her sight and was able to read again
The defining moment occurred on October 29, 2025. A team from the cornea unit at Rambam, led by Prof. Michael Mimouni, along with Prof. David Zadok from Shaare Zedek Medical Center and Prof. Eitan Livny from Beilinson Hospital, transplanted for the first time in a human a biological implant produced by Precise Bio from human corneal cells grown in a laboratory and printed using a 3D bioprinting system.
The patient, who was blind in the treated eye, regained vision in that eye after the surgery. This is the world's first transplantation of a functional, live-cell-based corneal implant produced through bioprinting.
Since then, the trial has been expanded, and transplants have been performed in five patients so far. The trial is an open-label, non-controlled Phase 1 study planned to include 15 patients. Its primary objective is to test safety and tolerability while simultaneously identifying initial signs of efficacy. The trial results are expected to be published in 2027 following the completion of follow-up.
Not the entire cornea, but the part that keeps it transparent
Despite the catchy moniker "printed cornea," it is important to be precise: The company does not replace the entire cornea. The implant replaces the endothelium, a thin layer of cells located on the inner part of the cornea, along with a collagen-based support layer.
Endothelial cells have an essential role: They pump excess fluid out of the cornea and keep it clear. When these cells are damaged, for example due to Fuchs' dystrophy or following cataract surgery, fluid accumulates in the cornea, causing it to swell and become cloudy, resulting in deteriorating vision. Today, the condition is treated by transplanting inner layers taken from the cornea of a deceased person.
"More than half of corneal transplants today are actually transplants of the endothelial layer," Batt explains. "Instead of taking this layer directly from a donor, we manufacture it on our production line. From the physician's perspective, the transplantation technique is very similar to the existing procedure, and post-operative treatment is similar as well."
One of the advantages of the cornea is the absence of blood vessels, which makes the immune system response relatively mild. Patients do not require heavy systemic immunosuppressive treatment, but rather eye drops alone, similar to what is customary after a corneal transplant from a donor.
From one donor to hundreds of patients
Precise Bio's technology may provide a solution to one of the most severe problems in the field: The global shortage of corneal tissue. Global research published in JAMA Ophthalmology estimated that for every 70 people in need of a transplant, there is only one available cornea. Approximately 15 million people remain without treatment that could restore their sight.
In Israel, as in many countries worldwide, corneas imported from overseas eye banks are used, but even after importing corneas, patients are still sometimes forced to wait years to receive a donation. Precise Bio's solution still requires a human donation, but instead of using one cornea for a single patient, cells are isolated from it and multiplied in the laboratory.
Batt says that today the company is capable of reaching 400 to 500 implants from a single donor. If this capability is proven in large-scale commercial manufacturing, it could turn a rare biological material into a product that can be manufactured in high volume and according to demand.
Batt adds that the printed implant features a higher density of endothelial cells: More than 4,000 cells per square millimeter, compared to approximately 2,000 to 2,500 in many donor tissues. The hope is that the high cell count will allow the implant to remain functional for a longer period, though according to him, this assumption will also need to be proven through long-term follow-up in humans.
Printing takes minutes, production takes weeks
Batt is not a biologist or a physician. He is a physicist by training who worked for years in the defense industry and at numerous companies, including Elbit Systems, Israel Aerospace Industries, and Orbotech. In his previous roles, Batt engaged in the development of complex multidisciplinary technological systems while simultaneously being exposed to the limitations of existing printing technologies. Understanding these limitations and existing needs led Batt to develop precise printing technology that can be adapted for printing live cells in controlled density and structure.
In 2015, he joined Prof. Anthony Atala, director of the Wake Forest Institute for Regenerative Medicine, one of the leading institutes in tissue engineering, and Prof. Shay Soker, an expert in molecular biology, and the three founded Precise Bio.
The company calls its process "4D printing." The printing itself takes minutes, but it is only part of a process that lasts several weeks. First, the cells are isolated, grown, and multiplied. After printing onto the support layer, the fourth dimension begins: Time. At this stage, in a controlled process lasting several days, the cells connect to one another and to the other layers, turning into functional tissue.
"We know how to freeze the cells and preserve the structural parts over time," Batt explains. "Before transplant surgery, it is possible to thaw the cells and take them out for printing and completion of the maturation process. The goal is to supply tissue on demand, so that the physician will not have to hope an available cornea will be present at the exact right time."
Manufacturing takes place under sterile conditions supervised by a quality control system. According to Batt, every batch is tested to verify cell properties, density, tissue thickness, and the absence of unwanted changes.
The seal of approval from an ophthalmology giant
In 2022, German medical equipment giant Carl Zeiss Meditec invested in the company. One of the company's products, an implant for the treatment of keratoconus disease, was developed within the framework of a collaboration between the companies and Zeiss. Alongside the investment, an agreement was signed under which Zeiss will serve as a partner for commercializing the technology.
For Batt, the entry of one of the world's largest companies in ophthalmology was an important sign, but even that did not compare to the moment he saw the implant working inside a human eye.
"When you found a biomed company around something that sounds like science fiction, raising money is very complex," he says. "After the transplant, a change occurred. Investors and international companies no longer look at this as a dream. Now there are patients."
The vision: Producing heart tissue and liver and kidney segments
Precise Bio's vision does not end with corneal manufacturing. The company is also working on retinal tissue, and in the past printed cardiac muscle tissue as part of experiments. Batt estimates that tissue sections, including portions of the heart, liver, and kidney, will reach clinical use within 10 to 15 years, before entire organs do.
The major challenge in an organ like a heart or kidney is not just printing its shape, but integrating many types of cells, building a blood vessel system to nourish them, and connecting the organ to the body's nerves and tissues. According to him, transplanting a printed heart or kidney is still decades away, but he notes it is entirely realistic.
In tissues where there is a risk of rejection, the company intends to use the patient's own cells. In this way, it will be possible to reduce the risk of rejection and the need for immunosuppressive drugs.
A breakthrough, but not yet a medical product
Transplanting tissue into five human beings is an extraordinary milestone, but the road to a commercial product is still long. After successfully completing the trial, Precise Bio will be required to test the product in larger studies while simultaneously upgrading manufacturing facilities to meet commercial product standards.
Even so, something fundamental has already changed; the breakthrough has occurred. A decade ago, the question was whether it was possible at all to print living tissue and transplant it into a human. Today, the questions are how long it will hold up, how many implants can be produced, and at what price.
"I don't think there is an organ about which it can be determined that we will never succeed in manufacturing," Batt says. "The road ahead is still long, but we showed that the technology is possible. The cornea is the first. I promise you it will not be the last." In Pirkei Avot it is written: "It is not your duty to finish the work, but neither are you at liberty to neglect it."