With support from researchers and the Colossal Foundation, the non-profit arm of Colossal Biosciences, a zoo elephant receives EEHV vaccine, propelling conservation and future woolly mammoth projects.
With the UN reporting that over 1 million species are at risk of extinction, scientists around the world have been developing innovative strategies to protect the endangered species. The Asian elephant is one species scientists have been particularly invested in protecting. Since being listed as endangered by the International Union for Conservation of Nature in 1986, the Asian elephant has faced continued declines due to habitat loss, human conflict, and the deadly elephant endotheliotropic herpesvirus and is currently down to less than 50,000 individuals.
EEHV — a leading cause of mortality for adolescent elephants in captivity — has been the subject of notable research, given its 85% mortality rate and lack of cure or vaccine. Earlier this year, a novel EEHV vaccine was administered to a 40-year-old Asian elephant named Tess living at a zoo.
This vaccine, developed by virologists at the Baylor College of Medicine with the backing of organizations like the International Elephant Foundation and the de-extinction disrupters Colossal Biosciences, substantially advances global elephant conservation efforts and furthers the potential of reviving the centuries-extinct woolly mammoth.
“The living populations of Asian elephants are critical for the restoration of the woolly mammoth, but more importantly, for the preservation of the elephant lineage. We’re thrilled to advance science to benefit both existing and future generations of elephants and mammoths,” Colossal Biosciences representative Justin Quinn said in a statement.
Eradicating EEHV
Discovered in 1995 at the Smithsonian National Zoo in Washington, D.C., EEHV is a latent virus that has evolved alongside Asian elephants for millions of years. While EEHV is widespread throughout the species’ entire population, it mainly impacts young individuals in human care who lack the natural antibodies to ward off the disease.
EEHV is known to strike elephants without warning, resulting in hemorrhaging and ulcers that ultimately lead to organ failure and death — usually within 24 hours or less from the initial onset of symptoms.
With the disease killing at least 90 elephants over the past 20 years, scientists have been feverishly working to eradicate EEHV, which has been notoriously difficult to study given its ongoing inability to be cultured in a laboratory setting.
In 2009, virologist and Baylor professor Paul Ling, Ph.D., became involved in the study of EEHV after Mac — a 2-year-old Asian elephant at the Houston Zoo — died of the disease the year prior. Since then, Ling has become the world’s leading EEHV researcher and has been pivotal in the development of a vaccine to confer disease resistance in the Asian elephant.
The new mRNA vaccine — first administered on June 18 — is expected to induce antibodies against the disease with no adverse side effects. Tess, the first recipient, is currently being monitored for blood antibody levels and potential reactions.
“She’s a great candidate for this because we get regular routine blood collections on her and we can administer the vaccine and follow it along to make sure that it’s doing what we want the vaccine to do,” said Houston Zoo’s elephant supervisor Kristin Windle.
The vaccine, which has been under development for 15 years, isn’t expected to cure elephants of the virus but can proactively defend the young before they contract the disease.
“[In the vaccine are] parts of the elephant herpesvirus that we think are important for the virus to attach to and get into host cells, which is very similar to how the COVID vaccine is manufactured,” Ling said. “What we hope that will do is train the elephant’s immune system to recognize different parts of the virus.”
If the vaccine is proven effective, Ling plans to share it with vulnerable populations, both captive and wild, and leverage its development to extend protection to African elephants, which are significantly less susceptible to EEHV. With the continued funding from Colossal Biosciences, Ling proceeds to accelerate advancements toward a novel EEHV vaccine and, eventually, monoclonal antibody treatments.
The Asian Elephant’s Colossal Future
With a potentially life-saving vaccine on the horizon, we can expect massive things in store for the Asian elephant. As a keystone species, revitalizing the Asian elephant will have ecosystem-wide impacts that can lead to greater biodiversity and ecological resilience in a local area.
As the woolly mammoth’s closest living relative (with 99.6% similar DNA makeup), the Asian elephant’s resistance to EEHV has also furthered Colossal Biosciences’ de-extinction goals and led to a greater understanding of the woolly mammoth’s physiology.
“Colossal’s commitment to eradicating EEHV’s deadly effect on elephants will also serve to protect our future populations of woolly mammoths,” said the company’s co-founder and CEO Ben Lamm to discovery.com. “This research enhances our understanding of elephant, and therefore mammoth, immune responses and will allow Colossal to arm both elephants and mammoths with traits to protect them against this deadly disease.”
With the company hoping for woolly mammoths to make a comeback by 2027, advancing elephant conservation has been a vital aspect of ensuring the development of a viable elephant-mammoth hybrid species within that time frame.
Recently, Colossal Biosciences surpassed another milestone in elephant conservation when it announced the development of Asian elephant induced pluripotent stem cells crucial to performing genomic edits and understanding aspects of the species’ complex development and gestation cycle. Not only do these iPSCs allow for the development of an elephant-mammoth hybrid embryo, but they also inform potential captive breeding and rewilding strategies for both species.
“We knew when we set out on the woolly mammoth de-extinction project that it would be challenging, but we’ve always had the best team on the planet focused on the task at hand,” Lamm said in a press release. “This is a momentous step, with numerous applications, that we are proud to share with the scientific community. Each step brings us closer to our long-term goals of bringing back this iconic species.”
As Asian elephants continue to face the risk of extinction, efforts like these expand hope for the species’ future and emphasize the importance of taking innovative approaches to conservation. With companies like Colossal Biosciences in the mix, there’s no telling where this advancement will take us. Perhaps to a future where woolly mammoths and Asian elephants coexist?