Focus on Arts and Ecology

• Scientists have described three new frog species that dwell exclusively in the spiky leaves of pandan trees in Madagascar’s eastern rainforests.
• While the frogs are new to science, locals have observed them for generations, and they’ve been given names in Malagasy.
• The frogs have a unique life cycle completely restricted to the trees, meaning they entirely depend entirely on intact pandan trees.
• Pandan trees, from the genus Pandanus, are threatened by deforestation driven by mining, agriculture and development, while slashing, burning and deforestation threaten Madagascar’s extraordinary biodiversity in general.

Scientists have described three new frog species that dwell exclusively in the spiky leaves of pandan trees in Madagascar’s eastern rainforests.

Lead researcher Hugh Gabriel, from the Technical University of Braunschweig in Germany, described the frogs’ sounds as “soft clicks that sound like rain falling on leaves.” And he would know. Gabriel and his team spent years braving the razor-sharp leaves to reveal not just the new frogs but entire communities dependent on the water that collects in the grooves and nooks of Pandanus trees.

“Each tree was like a treasure chest; once we got past the jagged, barbed leaves, there was a wealth of biodiversity within each plant,” Gabriel told Mongabay in an email. “I spent my research days crashing towards the center of these trees where the water collects, alongside my guide Evariste.”

While the frogs are new to science, many locals, including Gabriel’s local guide Evariste Desire were already aware of the frogs. “They’ve been seen by Malagasy people for thousands of years, known as the secretive Sahona vakoa, or ‘frogs of the Pandanus,'” Gabriel said.

Recognizing the frogs as new species, Gabriel said, was “a gradual event — a slow assembly of different observations that culminated in the declaration that it was, indeed, a new species.” While studying frogs in the Guibemantis genus, he noticed an unusual specimen that didn’t match known species descriptions. Further investigation over several years with mentor Miguel Vences, also at Braunschweig, led to the naming of three new Pandanus-dwelling frog species — Guibemantis rianasoa, G. vakoa and G. ambakoana — in the journal Zootaxa.

“The frogs were all given names in Malagasy to enable their description to be more accessible by local guides and frog-enthusiasts,” Gabriel said. “Rianasoa is named for a beautiful waterfall in Mantadia National Park, where the frogs can also be found. The clear water of the waterfall’s pool, reflecting the blue and green shadows of the forest, reminded Evariste [Desire] and I of the coloration of the beautiful new frog. Vakoa is the Malagasy word for Pandanus, and ambakoana means ‘living within Pandanus.’”

The frogs have a unique life cycle completely restricted to the trees. Up in the foliage, the frogs lay their eggs in gel masses on the leaves. When the tadpoles hatch, they drop into tiny pools of rainwater trapped by the leaves. The tadpoles grow into froglets that mature among the spiky leaves, coming out only to breed following the same unusual cycle, known only in one other genus of frogs.

This arboreal lifestyle means the frogs depend entirely on intact Pandanus trees. “If Pandanus trees are removed, all three species will suffer,” Gabriel said.

Pandanus trees are themselves a unique ecosystem. The rainwater in their leaf axils provides habitat not just for frogs and tadpoles. Crabs, spiders, day geckos, snakes, katydids, ant colonies and fungi are also regularly found within these trees.

They’re also widespread enough that logging poses less of an immediate threat than deforestation driven by mining, agriculture and development. Slashing, burning and deforestation threaten the island’s extraordinary biodiversity.

Climate change presents another conservation challenge for the rare frogs. Their life cycle depends on sufficient rainfall to fill Pandanus leaf pools, but shifting precipitation patterns and increased droughts due to climate change could quickly render their arboreal homes uninhabitable.

What’s needed to protect the frogs? “The simple answer is the preservation of rainforest habitat in Eastern Madagascar,” Gabriel said. But Madagascar’s economy is struggling, and “it’s not easy to tell struggling farmers not to clear land to make a living.”

He cited Mitsinjo, a small ecotourism initiative focused on forest restoration, frog conservation, environmental education, lemur monitoring, and improvement of the members livelihoods, as, “a good example of local-led tourism and sustainable development.”

“Mitsinjo means look into the future,” Desire said.

Banner image of Guibemantis rianasoa, a new frog species from Madagascar. Image courtesy of Hugh Gabriel

Liz Kimbrough is a staff writer for Mongabay and holds a Ph.D. in ecology and evolutionary biology from Tulane University, where she studied the microbiomes of trees. View more of her reporting here.

Citation:

Gabriel, H., Rothe, L.-D., Köhler, J., Rakotomanga, S., Edmonds, D., Galán, P., … Vences, M. (2024). Unexpected diversity and co-occurrence of phytotelmic frogs (Guibemantis) around Andasibe, one of the most intensively surveyed amphibian hotspots of Madagascar, and descriptions of three new species. Zootaxa, 5397(4), 451-485. doi:10.11646/zootaxa.5397.4.1

Credits:

Lizkimbrough, Editor

(Sources: Mongabay)

• Around the world, mangrove forests have undergone a decades-long decline that is just now slowing to a halt.
• In Pakistan, by contrast, mangroves expanded nearly threefold between 1986 and 2020, according to a 2022 analysis of satellite data.
• Experts attribute this success to massive mangrove planting and conservation, as well as concerted community engagement.
• Many in Pakistan are looking to mangroves to bolster precious fish stocks and defend against the mounting effects of climate change — even as threats to mangroves, such as wood harvesting and camel grazing, continue with no end in sight.

KARACHI — His sandaled feet drenched in black mud, Rashid Rasheed points to one of the mangrove nurseries he’s been looking after for the past few years. With wooden walls topped by green netting, a dozen nurseries shelter thousands of saplings.

Rasheed, a researcher and nursery expert with the government of Balochistan province in Pakistan, has been leading a drive to establish nurseries in the coastal town of Dam. The goal is to expand and enhance the town’s scattered patches of natural mangrove forest, which have shriveled due to human activities.

“These nurseries have 50,000 saplings that are ready to be transported to the creeks for planting” Rasheed tells Mongabay.

Rasheed’s work is part of a five-year project initiated in 2019 by the Chinese Academy of Sciences’ South China Sea Institute of Oceanography that has planted mangroves on 16 hectares (40 acres) at Dam, and at other sites in Balochistan and neighboring Sindh province.

It’s one of many projects aiming to restore Pakistan’s mangroves. These semiaquatic trees offer a host of benefits, such as protecting coasts against storms and rising sea levels, providing habitat for fish, birds, and other wildlife, sequestering carbon better than most other ecosystems on Earth, and sustaining the livelihoods of some 120 million people globally, according to the IUCN.

Around the world, mangrove forests have undergone a decades-long decline that’s just now slowing to a halt. But Pakistan bucks this trend. The country’s mangroves expanded from 48,331 hectares in 1986 to 143,930 hectares in 2020 (119,430 to 355,659 acres), a nearly threefold increase, according to a 2022 analysis of satellite data. “It is because of the constant endeavor by government and NGOs,” the analysis states, citing restoration, research, and awareness-raising campaigns “now being religiously carried out to conserve and regrow mangroves” by local, national and foreign bodies. Fishing communities, who depend on mangroves for fuel, shelter and as fish nurseries, are often key to the success of Pakistan’s mangrove restoration, providing the labor for planting and protection.

Many in Pakistan are looking to mangroves to bolster precious fish stocks and defend against the effects of climate change — even as threats to mangroves, such as wood harvesting and camel grazing, continue with no end in sight.

Pakistan’s regreening fringe

About three-quarters of Pakistan’s 1,050-kilometer (652-mile) coastline lies in Balochistan province, where the remaining mangrove trees stand in dispersed patches. The rest of the coast lies in Sindh province, where more than 90% of the country’s mangroves live. There, the Indus Delta stretches over 600,000 hectares (1.5 million acres), an intertidal wetland home to the world’s seventh-largest mangrove forest, which supports the livelihoods of at least 100,000 people in fisheries.

However, many people in the once-prosperous delta have been forced to leave in recent decades, as damming and diversions of the Indus River, compounded by sea level rise, have led to the sea encroaching, freshwater becoming scarce, and farmland turning saline. Pakistan’s alarming vulnerability to climate change is well documented. The devastating mega floods in 2022 — made 75% more intense by climate change, according to scientists — killed at least 1,700 people, displaced 8 million, and inflicted losses of $30 billion.

To cope with these and other environmental disasters, national and provincial governments under various ruling parties have carried out massive tree-planting projects to enhance terrestrial forest cover since 2008. Among these at the national level, the ongoing Ten Billion Tree Tsunami, initiated in 2018 by then-prime minister Imran Khan, includes restoring mangroves. The Sindh provincial government has undertaken various efforts to increase mangrove forests, its Forest Department having established a mangrove conservation wing in 1990.

In one of the more market-oriented initiatives, in 2015 the Sindh Forest Department entered a 60-year public-private partnership with U.K-based blue-carbon developer Indus Delta Capital that aims to restore and protect 225,000 hectares (556,000 acres) of mangroves and improve the livelihoods and well-being of 42,000 people living among them. The project had planted nearly 74,000 hectares (183,000 acres) of mangroves by the end of 2021, project documents state, and its first two carbon credit auctions generated revenues worth $40 million, according to media reports.

In recent years, as the effects of climate change have begun to devastate Pakistan, such restoration projects have been supported by more overarching policies aiming to protect ecosystems and enhance climate resilience. These include the country’s National Adaptation Plan, released in August, its Protected Areas Initiative and Ecosystem Restoration Initiative, as well as its Living Indus Project, launched in 2022 to make the Indus Basin climate-resilient by centering wetland restoration. The government has also been proactive in protecting mangroves, such as declaring the Indus Delta region a protected area in 2010.

Keys to survival

“The wetland restoration efforts demonstrate Pakistan’s commitment to environmental conservation and sustainable development,” Bilquees Gul, co-founder and former director of the Institute of Sustainable Halophyte Utilization at the University of Karachi, tells Mongabay. “The success of these initiatives is evident in the increased coverage of mangrove forests in Pakistan and the improved health of these ecosystems.”

Globally, large-scale tree plantings and carbon-credit projects, including ones in Pakistan, have come under increased scrutiny. Mangrove planting in particular is often frustrated by low survival rates. A 2015 literature review that included 54 studies of mangrove restoration projects globally found that the median rate of mangrove survival in “developing” countries, as assessed usually only a year or two after restoration, was 44.7%.

Pervaiz Amir, a water expert and steering committee member of the Global Water Partnership in Pakistan, said Pakistan’s mangrove plantation survival rate is initially right in line, at 40% to 45%, but it increases with restocking.

“By restocking … we mean gap filling and planting more trees where saplings did not germinate or [were] destroyed for one or another reason,” Amir says. Including restocking, Gul puts the survival rate over the last two years at 90%.

Community engagement is another key, experts say, especially finding ways for people to benefit from the mangroves.

“Community members have been benefiting from our massive plantation drives” in Sindh, Shehzad Sadiq Gill, a divisional forest officer with the Sindh Forest Department, tells Mongabay. “We hire them in developing mangrove nurseries, and they are paid wages for transporting the saplings from nurseries to the [planting] site.”

In Ibrahim Hyderi, a fishing village in Pakistan’s capital, Karachi, just northwest of the Indus River Delta, the port was teeming with fishing boats when Mongabay visited in August. Four forest guards in khaki uniforms stood ready to set sail with their boss, range forest officer Zeeshan Ali Chang, to patrol natural and restored areas of the local mangrove forest. The guards are community members hired by the Sindh Forest Department during restoration initiatives.

The goal is to protect both the mangrove and the community’s interests from illegal woodcutters and camel grazers, Chang says. After engagement with the community, the Sindh Forest Department designated certain patches of mangrove for grazing, while instituting penalties for those who go beyond. “These people have been living here for generations and have been dependent on the mangroves for livelihood,” Chang says.

Another crucial boon the mangroves provide local people: fish. Akbar, a young fisherman in Ibrahim Hyderi who doesn’t give a surname, says he values the mangrove forests as nurseries for many varieties of fish and shrimp. He says he believes fish catches are good because of the mangrove forests, which he calls timar trees in the local Sindhi language.

“These timar trees are the lifeline for the fishing community,” Akbar says. “We have fishes, shrimps and crabs, which are a source of our livelihood. These are in abundance where timars are present.”

Threats to the mangroves

Despite the successes, numerous forces are pushing back against the expansion of Pakistan’s mangroves. The country is under a major economic and energy crisis, and households and businesses are turning to wood as fuel. Half of the population has no access to clean fuel for cooking and, according to one estimate, around 68% uses firewood. Mangroves remain under constant threat from woodcutters, both individuals and syndicates. There’s little data tracking such losses, but anecdotal observations suggest they’re significant.

Tariq Alexander Qaiser, an architect and environmentalist who’s been working to conserve the mangrove forest on Bundal Island off Karachi, tells Mongabay deforestation on the island is increasing, both for local household use and commercial sale.

“First, the trees are chopped off and left to dry,” Qaiser says. “Later on, the wood is loaded on boats, giving an impression that they [woodcutters] are taking ‘dead’ wood.”

Livestock grazing, especially by camels, raised for meat, milk and transportation, is a major threat to recently planted saplings and mature forests alike, in many parts of Sindh and Balochistan.

Pollution poses yet another risk. Solid waste, like the floating single-use plastic bags surrounding the dinghies at Ibrahim Hyderi, can block waterflow to mangroves or break their roots and branches, stunting or killing them. Untreated sewage, which can acidify local waters, slows mangrove growth, according to Mehran Ali Shah, chair of the Pakistan FisherFolk Forum, a Karachi-based civil society organization that advocates for fishing and agricultural communities.

“This ocean acidification … is rising because of untreated waste released into the ocean, and seashores have been turned into dumping yards in Karachi,” Shah tells Mongabay. “There are no treatment plants installed here.”

And then there are hydrological factors, including the impeded flow of freshwater into the Indus Delta due to upstream dams and barrages, compounded by rising sea levels. The result is reduced silt reaching the delta and elevated salinity, both of which slow mangrove growth and push many fish species away, Shah says.

For his part, Qaiser blames the altered hydrology for diminishing mangrove diversity. “After its inception, Pakistan had eight species of mangroves, but of eight species, four have vanished and … two are on the brink of vanishing. This is just because of the impeded flow of [fresh]water into the Indus Delta,” Qaiser says.

These problems go far beyond mangroves: The National Adaptation Plan notes that rising saltwater intrusion into the Indus Delta is increasing salinity inland, reducing freshwater supplies and arable land, and sending residents to live in Karachi. There, resources are already strained, it says, and while some areas of the city are already submerged due to rising sea levels, many more will follow in the next 35 to 45 years. The plan promotes mangrove restoration to help address these issues.

“Stress on mangrove forests comes from multiple factors, such as chopping down of trees either by mafias or by the local community for fuel,” Ali Tauqeer Sheikh, an independent expert on climate change and development, tells Mongabay. “Sea, however, is a grave issue which is taking its toll on not only [the Indus] Delta but poses a threat to the agriculture of the area.”

A look into the future

Despite the challenges, the Sindh Forest Department is doubling down on mangrove restoration. According to Gill, citing the department’s own numbers, the province’s mangrove cover had shrunk to 80,000 hectares (198,000 acres) by 1990, when it established its mangrove conservation wing. Under the recovery program, mangroves have since expanded to 240,000 hectares (593,000 acres), and the goal is to get them up to 350,000 hectares (865,000 acres) in the future.

“Indeed, this is a challenging task to complete, but we believe we can achieve this given our restoration track record,” Gill says.

Banner image: Workers at a mangrove nursery in Dam, a coastal town in Pakistan’s Balochistan province. Image by Ayaz Khan for Mongabay.

Ayaz Khan is a researcher and journalist based in Pakistan covering climate change Follow him on X: @Ayaz_Jurno.

Citations:

Hussain, M., & Rahman, A. (2022). Monitoring spatial and temporal distribution, pattern, and trend prediction of coastal mangroves in Pakistan using geospatial techniques. Science for Sustainable Societies, 15-29. doi:10.1007/978-981-19-2738-6_2

Bayraktarov, E., Saunders, M. I., Abdullah, S., Mills, M., Beher, J., Possingham, H. P., … Lovelock, C. E. (2015). The cost and feasibility of marine coastal restoration. Ecological Applications, 26(4), 1055-1074. doi:10.1890/15-1077

Credits:

Rebecca Kessler, Editor

(Sources: Mongabay)

By E360 Digest, February 7, 2024 

⁠Europe saw a record drop in fossil fuel power last year, according to a new analysis. For the first time, wind supplied more electricity than natural gas.

The E.U. power sector is undergoing a “monumental shift,” said Sarah Brown, an analyst at the energy think tank Ember, which undertook the analysis. “Fossil fuels are playing a smaller role than ever as a system with wind and solar as its backbone comes into view.”

In 2023, coal generation fell by 26 percent, while gas generation fell by 15 percent. Along with a record buildout of renewables and a downturn in demand, the decline of fossil fuels led to an unprecedented drop in emissions from generating electricity, which fell by 19 percent.

The figures are welcome news in Europe, which is working to shift away from fossil fuels even as war and inflation roil energy markets. After Russia invaded Ukraine, exports of natural gas to Europe dwindled. The drop-off sparked fears of a resurgence of coal, and it prompted the building of new infrastructure to import liquefied natural gas from overseas.

But by ramping up wind and solar and tamping down on demand, Europe avoided a surge in coal burning and kept the use of natural gas in check. Altogether, renewables generated nearly half of Europe’s power last year, while fossil fuels supplied roughly a third, and nuclear around a quarter.

Looking ahead, analysts say Europe will need to double down on renewable power to keep up with the projected rise in demand from the adoption of heat pumps and electric cars.

(Sources: E360)

Despite strong interest in using artificial intelligence to make research faster, easier and more accessible, researchers say they need more support to navigate its possibilities. 

By Miryam Naddaf, 04 February 2025

Using artificial intelligence (AI) tools for processes such as preparing manuscripts, writing grant applications and peer review will become widely accepted within the next two years, suggests a survey of nearly 5,000 researchers in more than 70 countries by the publishing company Wiley.

The survey asked researchers how they are currently using generative AI tools — which include chatbots such as ChatGPT and DeepSeek — as well as how they feel about various potential applications of the technology. The results suggest that the majority of researchers see AI becoming central for scientific research and publishing (see ‘Acceptable use’). More than half of the respondents think that AI currently outperforms humans at more than 20 of the tasks given as example use cases, including reviewing large sets of papers, summarizing research findings, detecting errors in writing, checking for plagiarism and organizing citations. More half of the survey participants expect AI to become mainstream in 34 out of 43 use cases in the next two years.

“What really stands out is the imminence of this,” says Sebastian Porsdam Mann at the University of Copenhagen, who studies the practicalities and ethics of using generative AI in research. “People that are in positions that will be affected by this — which is everyone, but to varying degrees — need to start” addressing this now, he adds.

Wiley, headquartered in Hoboken, New Jersey, posted the survey findings online on 4 February. Josh Jarrett, senior vice-president and general manager of the publisher’s AI growth team, says he hopes they will serve as a road map for innovators and start-ups looking for opportunities to develop AI tools. “There's broad acceptance that AI is going to reshape the research field.”

Limited uses

The survey polled 4,946 researchers worldwide, 27% of whom are early-career researchers. Perhaps surprisingly, says Jarrett, the results show that “people aren't really using these tools much in their day-to-day work”. Only 45% of the first wave of respondents (1,043 researchers) said that they had actually used AI to help with their research, and the most common uses they cited were translation, proofreading and editing manuscripts (see ‘Uses of AI’).

Although 81% of these 1,043 respondents said they had used OpenAI’s ChatGPT for personal or professional purposes, only one-third had heard of other generative-AI tools such as Google’s Gemini and Microsoft’s Copilot. However, there are clear differences across countries and disciplines, with researchers in China and Germany, as well as computer scientists, being the most likely to use AI in their work.

The majority of survey participants expressed interest in expanding their AI use. About 72% want to use AI for preparing manuscripts in the next two years — for tasks such as detecting errors in writing, plagiarism checks and organizing citations. Sixty-two per cent think that AI already outperforms humans in these tasks (see ‘Who does it better: humans or AI?’).

Around 67% of respondents also expressed interest in using AI to handle large amounts of information, for example helping to review the literature, summarizing papers and processing data. Early-career researchers showed greater interest than did more senior colleagues in using AI for writing grant applications and finding potential collaborators. “These are both things that come easier with experience and seniority,” says Porsdam Mann. “Using AI will help even those things out a little bit.”

However, researchers are less convinced about AI’s capabilities in more-complex tasks such as identifying gaps in the literature, choosing a journal to submit manuscripts to, recommending peer reviewers or suggesting relevant citations. Although 64% of respondents are open to using AI for these tasks in the next two years, the majority thinks that humans still outperform AI in these areas.

Obstacles and opportunities

Despite a burgeoning interest in AI tools, the survey suggests that researchers need more support to use them confidently. Nearly two-thirds of respondents said that a lack of guidance and training is preventing them from using AI to the extent that they would like (see ‘Causes for concern’). Researchers are also worried about how safe it is to use these tools: 81% of respondents said they had concerns about AI’s accuracy, potential biases, privacy risks and the lack of transparency in how these tools are trained.

“We think there's a big obligation of publishers and others to help educate,” says Jarrett. About 70% of respondents want publishers to provide clear guidelines on what uses of AI are acceptable, and 69% think publishers need to help them avoid errors and biases.

“Some centralized training must be carried out, and that should be made mandatory just like good clinical-practice training is mandatory across the world,” says Tejaswini Arunachala Murthy, an intensive-care nutritionist at the University of Adelaide in Australia who took part in the survey. “We are ready to give the time. We are ready to learn, and we want to learn,” she adds. “All these AI researchers … need to train us how to use it appropriately.”

Wiley is currently interviewing more researchers and collecting feedback to update its own guidelines for using AI, which it plans to release in the coming months. These guidelines will help researchers to better understand how to use AI safely in research, including when human insight is necessary and what disclosures should be made. “I don't think any of us are ready to recommend this tool over that one,” says Jarrett. The aim is to “give people some general guidelines of how to stay safe and start to share best practice”.

(Sources: Nature)

The small trial will help to establish whether kidneys from genetically modified pigs can be transplanted into people safely and effectively. 

By Smriti Mallapaty & Max Kozlov, 04 February 2025

The first clinical trial testing whether pig kidneys can be safely transplanted into living people has been approved by the US Food and Drug Administration (FDA). As part of the trial, which will begin later this year, kidneys from genetically modified pigs will be transplanted into people with chronic kidney disease whose organs no longer function independently.

The FDA’s green light will bring the experimental procedure a step closer to one day supplying organs to the thousands of people who are waiting for a donor organ. “The start of formal clinical trials is very exciting,” says Jay Fishman, a specialist in transplant infectious diseases at Massachusetts General Hospital in Boston.

About half a dozen people in the United States and China have received organs from genome-edited pigs — kidneys, hearts, liver and a thymus — but the surgeries were approved on compassionate grounds, meaning the patients were very sick and had no other options. Most recipients did not survive beyond a few months after the transplants for various reasons, including that they were too sick to cope with major surgery.

“The humans who have received xenotransplants have made a tremendous contribution to our field,” Fishman says. But formal clinical trials are standardized, and can therefore produce important information, including crucial safety and efficacy data, to move the field forwards, he says.

First trial

Six individuals will initially be enrolled in the trial, according to United Therapeutics, the biotechnology firm, based in Silver Spring, Maryland, and Research Triangle Park, North Carolina, that is running the trial. The trial will include people with end-stage kidney disease, aged 55–70 years old, who are not eligible for conventional kidney transplantation for medical reasons or are not likely to get one in the next five years and will possibly die waiting. Patients will be closely monitored for about six months for serious adverse events, infectious diseases and signs of kidney damage, and then followed up with for the rest of their lives.

The trial will assess efficacy by tracking how many participants — and transplanted kidneys — survive the procedure, and for how long. It will also measure how well the kidneys filter blood and will track changes in the participants’ quality of life.

The FDA has mandated pauses between patients to make sure there are no surprises, Fishman says. A monitoring committee will review safety and efficacy data for the first six participants, before deciding whether the trial should be expanded to up to 50 individuals.

Trials will enable researchers to select people who are in better health than those first compassionate-use recipients to assess the transplant’s safety and efficacy, says Muhammad Mohiuddin, a surgeon and researcher at the University of Maryland School of Medicine in Baltimore.

The success of this trial will pave the way for longer-term, larger clinical trials, says Wayne Hawthorne, a transplant surgeon at the University of Sydney in Australia.

Mohiuddin, who in 2022 led the first pig-heart transplant into a living person, says he is in the process of submitting a request to the FDA to start clinical trials, but adds that the heart is a more difficult organ to get approval for.

Another company, eGenesis in Cambridge, Massachusetts, has also submitted a request to the FDA to launch a xenotransplant trial, says Fishman, who has advised both United Therapeutics and eGenesis on microbiology safety, and would be involved in an eGenesis trial should it be approved. In an e-mailed statement, eGenesis said that in December, it had received FDA approval to conduct three pig-kidney transplants under compassionate use. The company did not comment on the status of its clinical-trial application.

Modified pigs

Participants in the trials will receive kidneys from pigs that have been genetically modified to reduce the risk of the organs being rejected.

Each company breeds pigs with a unique set of genetic modifications. In the trials, United Therapeutics will use pigs with 10 genetic edits, whereas eGenesis’s animals have 69 edits — most of them designed to inactivate viruses that could be lurking in the pig genome.

The companies also use different pig breeds: eGenesis uses a miniature-pig breed to prevent the organs from growing once they’re transplanted, and United Therapeutics instead deactivates a pig gene to prevent the organ from continuing to grow after the transplant.

Only 5 people in the United States have received a pig-organ transplant, and the longest that a person has survived is 71 days — and counting. That means there are still several challenges ahead, as the new experiments test the long-term viability of the procedure.

For example, clinicians will have to manage antibodies produced against pig antigens to prevent organ rejection, Mohiuddin says. In addition, non-human primates that received pig kidneys have developed a condition in which their urine contains an excessive amount of protein, says David Cooper, a xenotransplant immunologist at Massachusetts General Hospital in Boston. Researchers have struggled to devise a method to manage this condition, and it remains to be seen if this will also affect people, he says.

There are also concerns that the pigs could have viruses or other infections that spread to the recipient. Fishman says that teams have learnt the importance of both screening the pigs and monitoring the recipients for infections.

Luhan Yang, chief executive of Qihan Biotech in Hangzhou, China, and one of the founders of eGenesis, hopes that the FDA’s approval will encourage counterpart regulatory agencies in Europe and China to consider similar trials. For decades, she has heard people say that xenotransplantation is around the corner. The trial announcement “is a breakthrough in the field”.

(Sources: Nature)