Sarasota scientists are studying sharks to try and improve human cancer treatments.
A team from Sarasota’s Mote Marine Laboratory is studying bonnethead sharks, juvenile nurse sharks and shark relatives, such as the skate, to find out why these animals are so healthy.
“I call them my marine mice,” MOTE senior scientist Carl Luer said. “It’s very rare to find a sick shark.”
Dr. Luer has been with MOTE for 38 years. He coordinates the non-profit’s marine biomedical research program and is at the forefront of shark research he hopes could help people with cancer.
“We think we’re on the edge of understanding some of the compounds that they produce that we hope we can develop into novel anti-cancer therapies,” Luer said.
The scientists are trying to find out what allows sharks to fend off cancer and other diseases. “We always keep our eyes open to see how we could apply this information to human health,” Luer said.
The researchers have identified key differences between shark and human immune systems. Sharks are all cartilage. They don’t have bone marrow or lymph nodes, which are key components to human immune health.
“We’re studying their immune system to understand what role the immune system might play in conferring a natural resistance to disease that these animals seem to have have,” Luer said.
“They’re very successful in their own world. They’ve been around for some 400 million years in some form or another,” he added.
It’s not uncommon to find tumors in other types of fish. In fact, in a lab, scientists have been able to induce cancer in bony fish, while sharks have resisted these attempts.
Dr. Luer knows sharks get a bad rap. “A lot of that damage was from the ‘Jaws’ movies, which we know are totally fiction. Sharks haven’t developed the cortex so we know they cannot rationally make the decisions that the ‘Jaws’ character seemed to make. It’s not possible, so they’re more of a feeding machine,” he said.
Most sharks don’t get longer than 4 or 5 feet. Fewer than 10 percent of sharks are involved in dangerous human interactions. In fact, Luer said, most sharks are more scared of humans than we are of them.
The scientists want to develop a culture of cells that they can use in the lab without having to catch new animals. This would lessen the need for live sharks, which are caught in waters near Florida. While the scientists say they use low numbers of common animals, they are conscious of conservation issues.
“We’re very aware of the need that we do not want to rely on these animals as a constant supply of tissue,” Luer said.
Track Great Whites: Mote scientist helping OCEARCH tag sharks
Earlier this month Dr. Robert Hueter from Mote joined OCEARCH to help track great white sharks. OCEARCH is a leading shark non-profit research organization.
The researchers went off the coast of the eastern end of Long Island, near Montauk.
The area is known to have baby white sharks, which is of interest to scientists who want to protect great white populations.
While on expeditions, OCEARCH teams catch great whites to gather information on them. After reeling a shark in, researchers have about 15 minutes to collect genetic samples, blood and other information.
They also attach tracking devices to the animals. Trackers allow the researchers to see where sharks travel to during their lives. “It’s pointing tantalizingly toward what we think may be places where they’re mating and where they’re giving birth to their young,” Hueter said. “These are the kinds of things that shark scientists try to find out about their research subjects.”
“The nursery area where these young sharks grow up is vital to the survival of the species,” he said.
In the past, we have allowed shark populations to dwindle. However, research and protection efforts have helped identify critical areas that need to be protected. That’s allowed us to “restore the ocean back to a more natural state” with higher numbers of great white sharks.
“White sharks are what we call top predators … They’re the lions of the sea in this part of the ocean, and we need them for balance,” Hueter said. “We need them for a healthy ocean.”
“We start with research and education,” he added. “By reaching people and exciting people about the importance of these sharks, we really help to affect policy. But before that we do the research to understand where these animals are going.”
That helps researchers identify states and countries they should work with “to protect these magnificent animals,” Hueter said.
Mote first worked with OCEARCH to study the effects of the Deepwater Horizon oil spill on sharks in waters near southwestern Florida. Hueter has since been on nine expeditions. They have concentrated on the northwest Atlantic, going up and down the East Coast and into the Gulf.
Hueter also works on conservation efforts throughout the world, including in Cuba, Mexico and an upcoming project in Puerto Rico.