When Karen Davis attended a presentation at a dental conference in 2013, she unexpectedly discovered a service that could help her daughter, Madeline: storing stem cells derived from her teeth that potentially could be used in the future to treat her Crohn's disease.
"Even though this isn't a viable option today, I know how rapidly things can change."
Throughout high school, Madeline suffered from the painful autoimmune disorder, which wreaks havoc on the gastrointestinal system and can lead to life-threatening complications.
"I leave no stone unturned when it comes to medical care and this resonated with me," says Davis, a Dallas-based dental hygienist who was encouraged by advances in stem cell research. Later that year, when Madeline got her wisdom teeth extracted, Davis shipped them off to the Store-A-Tooth company in Massachusetts, where they will be kept frozen until needed. "Even though this isn't a viable option today, I know how rapidly things can change," says Davis. "To me, this was a worthwhile investment—I didn't want to miss out on an opportunity that would provide a pathway to a cure."
Karen Davis pictured with her daughter Madeline.
(Courtesy of Karen Davis)
The process itself was straightforward. Madeline's newly extracted wisdom teeth--baby teeth can be saved, too—were bathed in a special solution, loaded into a Styrofoam container lined with cold packs and sent to the stem cell company. There, a team harvested the dental stem cells from the pulp, then grew them in culture and cryogenically preserved them. Store-A-Tooth charges $1500-1749 for tooth collection and $120 per year for storage, while other dental pulp stem cell tissue banks cost $500-$600 upfront and in the $120 range annually for storage.
The rationale here is that if you missed out on banking your baby's umbilical cord blood, this gives you another chance to harvest their stem cells. "If their child later develops an illness that could be managed or even cured with stem cell therapy, this is an insurance policy," says Amr Moursi, DDS, PhD, chair of the department of pediatric dentistry at New York University College of Dentistry.
But is there a genuine potential here for some effective treatments in the relatively near future—or is this just another trendy fad? Scientific opinion is decidedly mixed. Stem cells have been heralded as the next frontier in medicine because of their versatility: with a little chemical coaxing, they can be transformed into different cell types, such as heart, blood or brain cells, to create tissue that can mend damaged body parts. Because they're taken from your own body, there's little chance of rejection, which means patients don't have to take strong antirejection drugs that can have all sorts of unpleasant side effects for the rest of their lives.
However, while stem cells are immature cells found in different tissues, ranging from abdominal fat to bone marrow, there is a vast difference between the stem cells found in cord blood and in teeth. Cord blood, which is culled from the umbilical cord when a baby is born, contains what are called hematopoietic stem cells (HSCs), which can mature into other blood cells. These type of stem cells have already been approved by the U.S. Food and Drug Administration to treat patients—especially children--with blood cancers, such as leukemias and lymphomas, and certain blood disorders like sickle cell anemia.
In contrast, stem cells in teeth are called mesenchymal stem cells (MSCs), which are found in dental pulp, the tissue in the center of the tooth that's filled with nerves and blood vessels. MSCs are adult stem cells normally found in the bone marrow that can transform into bone, fat, and cartilage cells, and also aid in the formation of blood stem cells.
"Right now we just don't have rigorous evidence that they can be used in that fashion and have real benefit."
Small studies on lab animals suggest that MSCs secrete growth factors—hormonal steroids or proteins—that can nurture ailing cells, act as powerful anti-inflammatory agents that could tame autoimmune disorders like the one that plagues Karen Davis's daughter, and may even generate new nerve and muscle tissue. Preliminary research suggests they potentially could treat medical conditions as varied as heart disease, spinal cord injury and type 1 diabetes by generating new cells, which can replace damaged or dead cells.
But this is all very early research and there's a vast difference between how cells behave in the tightly controlled environment of a lab versus the real world in a diverse population of human patients. "Right now we just don't have rigorous evidence that they can be used in that fashion and have real benefit," says Pamela G. Robey, PhD, chief of the skeletal biology section at the National Institute of Dental and Craniofacial Research at the National Institutes of Health.
Robey should know—she headed the research team that discovered stem cells in human baby teeth and in wisdom teeth more than fifteen years ago. She believes prospects are better using these stem cells for tooth repair: research suggests they may be able to fix cracked teeth, repair bone defects caused by gum disease, or in root canal therapy, where they can be used to replace infected tissue with regenerated healthy pulp.
In the meantime, though, there are no clinical applications for MSCs. "These tooth banking companies aren't doing their own research," says Leigh Turner, a bioethicist at the University of Minnesota who monitors stem cell clinics. "They cobble together reports of early research in humans or from animal studies in an effort to provide a narrative to make it seem like it is evidence based."
Still, in all fairness, tooth banking companies aren't making the kind of extravagant claims made by stem cell clinics, which operate in a gray area of the law and purport to treat everything from chronic lung disease to Alzheimer's. "We don't know when therapies will be available using these cells because the pace of research is hard to predict," says Peter Verlander, PhD, a molecular geneticist and chief scientific officer of Provia Laboratories, the parent company of Store-A-Tooth. "But for parents who regretted not banking their child's cord blood, especially if they later develop a disease like diabetes, this is another opportunity."
But the jury is still out if this is truly a good investment. Moursi, a national spokesperson for the American Academy of Pediatric Dentistry who fields queries about this practice from a dozen or so families a year, concludes: "If you could afford it, and know the risks, benefits and current limitations, then it is something to consider."
No human has run a distance of 100 meters faster than Usain Bolt’s lightning streak in 2009. He set this record at age 22. But what will Bolt’s time be when he’s 105?
At the Louisiana Senior Games in November 2021, 105-year-old Julia Hawkins of Baton Rouge became the oldest woman to run 100 meters in an official competition, qualifying her for this year's National Senior Games. Perhaps not surprisingly, she was the only competitor in the race for people 105 and older. In this Leaps.org video, I interview Hawkins about her lifestyle habits over the decades. Then I ask Steven Austad, a pioneer in studying the mechanisms of aging, for his scientific insights into how those aspiring to become super-agers might follow in Hawkins' remarkable footsteps.
Following the Footsteps of a 105-Year-Old SprinterNo human has run a distance of 100 meters faster than Usain Bolt’s lightning streak in 2009. He set this record at age 22. But what will Bolt’s time be when ...
A new virus has emerged and stoked fears of another pandemic: monkeypox. Since May 2022, it has been detected in 29 U.S. states, the District of Columbia, and Puerto Rico among international travelers and their close contacts. On a worldwide scale, as of June 30, there have been 5,323 cases in 52 countries.
The good news: An existing vaccine can go a long way toward preventing a catastrophic outbreak. Because monkeypox is a close relative of smallpox, the same vaccine can be used—and it is about 85 percent effective against the virus, according to the World Health Organization (WHO).
Also on the plus side, monkeypox is less contagious with milder illness than smallpox and, compared to COVID-19, produces more telltale signs. Scientists think that a “ring” vaccination strategy can be used when these signs appear to help with squelching this alarming outbreak.
How it’s transmitted
Monkeypox spreads between people primarily through direct contact with infectious sores, scabs, or bodily fluids. People also can catch it through respiratory secretions during prolonged, face-to-face contact, according to the Centers for Disease Control and Prevention (CDC).
As of June 30, there have been 396 documented monkeypox cases in the U.S., and the CDC has activated its Emergency Operations Center to mobilize additional personnel and resources. The U.S. Department of Health and Human Services is aiming to boost testing capacity and accessibility. No Americans have died from monkeypox during this outbreak but, during the COVID-19 pandemic (February 2020 to date), Africa has documented 12,141 cases and 363 deaths from monkeypox.
Ring vaccination proved effective in curbing the smallpox and Ebola outbreaks. As the monkeypox threat continues to loom, scientists view this as the best vaccine approach.
A person infected with monkeypox typically has symptoms—for instance, fever and chills—in a contagious state, so knowing when to avoid close contact with others makes it easier to curtail than COVID-19.
Advantages of ring vaccination
For this reason, it’s feasible to vaccinate a “ring” of people around the infected individual rather than inoculating large swaths of the population. Ring vaccination proved effective in curbing the smallpox and Ebola outbreaks. As the monkeypox threat continues to loom, scientists view this as the best vaccine approach.
With many infections, “it normally would make sense to everyone to vaccinate more widely,” says Wesley C. Van Voorhis, a professor and director of the Center for Emerging and Re-emerging Infectious Diseases at the University of Washington School of Medicine in Seattle. However, “in this case, ring vaccination may be sufficient to contain the outbreak and also minimize the rare, but potentially serious side effects of the smallpox/monkeypox vaccine.”
There are two licensed smallpox vaccines in the United States: ACAM2000 (live Vaccina virus) and JYNNEOS (live virus non-replicating). The ACAM 2000, Van Voorhis says, is the old smallpox vaccine that, in rare instances, could spread diffusely within the body and cause heart problems, as well as severe rash in people with eczema or serious infection in immunocompromised patients.
To prevent organ damage, the current recommendation would be to use the JYNNEOS vaccine, says Phyllis Kanki, a professor of health sciences in the division of immunology and infectious diseases at the Harvard T.H. Chan School of Public Health. However, according to a report on the CDC’s website, people with immunocompromising conditions could have a higher risk of getting a severe case of monkeypox, despite being vaccinated, and “might be less likely to mount an effective response after any vaccination, including after JYNNEOS.”
In the late 1960s, the ring vaccination strategy became part of the WHO’s mission to globally eradicate smallpox, with the last known natural case described in Somalia in 1977. Ring vaccination can also refer to how a clinical trial is designed, as was the case in 2015, when this approach was used for researching the benefits of an investigational Ebola vaccine in Guinea, Kanki says.
“Since Monkeypox spreads by close contact and we have an effective vaccine, vaccinating high-risk individuals and their contacts may be a good strategy to limit transmission,” she says, adding that privacy is an important ethical principle that comes into play, as people with monkeypox would need to disclose their close contacts so that they could benefit from ring vaccination.
Rapid identification of cases and contacts—along with their cooperation—is essential for ring vaccination to be effective. Although mass vaccination also may work, the risk of infection to most of the population remains low while supply of the JYNNEOS vaccine is limited, says Stanley Deresinski, a clinical professor of medicine in the Infectious Disease Clinic at Stanford University School of Medicine.
Other strategies for preventing transmission
Ideally, the vaccine should be administered within four days of an exposure, but it’s recommended for up to 14 days. The WHO also advocates more widespread vaccination campaigns in the population segment with the most cases so far: men who engage in sex with other men.
The virus appears to be spreading in sexual networks, which differs from what was seen in previously reported outbreaks of monkeypox (outside of Africa), where risk was associated with travel to central or west Africa or various types of contact with individuals or animals from those locales. There is no evidence of transmission by food, but contaminated articles in the environment such as bedding are potential sources of the virus, Deresinski says.
Severe cases of monkeypox can occur, but “transmission of the virus requires close contact,” he says. “There is no evidence of aerosol transmission, as occurs with SARS-CoV-2, although it must be remembered that the smallpox virus, a close relative of monkeypox, was transmitted by aerosol.”
Deresinski points to the fact that in 2003, monkeypox was introduced into the U.S. through imports from Ghana of infected small mammals, such as Gambian giant rats, as pets. They infected prairie dogs, which also were sold as pets and, ultimately, this resulted in 37 confirmed transmissions to humans and 10 probable cases. A CDC investigation identified no cases of human-to-human transmission. Then, in 2021, a traveler flew from Nigeria to Dallas through Atlanta, developing skin lesions several days after arrival. Another CDC investigation yielded 223 contacts, although 85 percent were deemed to be at only minimal risk and the remainder at intermediate risk. No new cases were identified.
How much should we be worried
But how serious of a threat is monkeypox this time around? “Right now, the risk to the general public is very low,” says Scott Roberts, an assistant professor and associate medical director of infection prevention at Yale School of Medicine. “Monkeypox is spread through direct contact with infected skin lesions or through close contact for a prolonged period of time with an infected person. It is much less transmissible than COVID-19.”
The monkeypox incubation period—the time from infection until the onset of symptoms—is typically seven to 14 days but can range from five to 21 days, compared with only three days for the Omicron variant of COVID-19. With such a long incubation, there is a larger window to conduct contact tracing and vaccinate people before symptoms appear, which can prevent infection or lessen the severity.
But symptoms may present atypically or recognition may be delayed. “Ring vaccination works best with 100 percent adherence, and in the absence of a mandate, this is not achievable,” Roberts says.
At the outset of infection, symptoms include fever, chills, and fatigue. Several days later, a rash becomes noticeable, usually beginning on the face and spreading to other parts of the body, he says. The rash starts as flat lesions that raise and develop fluid, similar to manifestations of chickenpox. Once the rash scabs and falls off, a person is no longer contagious.
“It's an uncomfortable infection,” says Van Voorhis, the University of Washington School of Medicine professor. There may be swollen lymph nodes. Sores and rash are often limited to the genitals and areas around the mouth or rectum, suggesting intimate contact as the source of spread.
Symptoms of monkeypox usually last from two to four weeks. The WHO estimated that fatalities range from 3 to 6 percent. Although it’s believed to infect various animal species, including rodents and monkeys in west and central Africa, “the animal reservoir for the virus is unknown,” says Kanki, the Harvard T.H. Chan School of Public Health professor.
Too often, viruses originate in parts of the world that are too poor to grapple with them and may lack the resources to invest in vaccines and treatments. “This disease is endemic in central and west Africa, and it has basically been ignored until it jumped to the north and infected Europeans, Americans, and Canadians,” Van Voorhis says. “We have to do a better job in health care and prevention all over the world. This is the kind of thing that comes back to bite us.”