Publisher Health

Ion channels in the nervous system are among the most important targets for insecticides. Understanding the structure of the channels is key for the identification of novel species-specific binding sites of agrochemicals. Researchers have revealed the structure and function of a potassium ion channel in fruit flies. Their newly obtained insights reveal the differences between human and insect channels, explain how known compounds affect the channel and propose new target sites for drugs. The research could help pesticide manufacturers design new drugs apt to specifically kill pest insects and parasites without affecting other animals like bees and mammals.
The Slowpoke potassium channels in Drosophila, the common fruit fly, are huge and complex proteins that sit inside the cellular membrane and selectively and rapidly transport vital potassium ions through it. They are found in all animals and are responsible for completing various tasks, most importantly in the brain and in muscle cells. The essential roles of the potassium channels signify the importance of targeting Slowpoke with newly developed insecticides in order to help overcome the global problem concerning the decrease in efficiency due to the growing pesticide resistance. Yet, there is always the risk of not aiming properly: “Ideally, you want insecticides to be really specific to the pest insect, avoiding drugs that are toxic for humans, or other animals, such as birds, rodents and beneficial insects like bees,” says Stefan Raunser, Director at the Max Planck Institute of Molecular Physiology in Dortmund, and lead author of the study.
In order to design drugs that are specific for pest insects, scientists need high-resolution structures of the ion channels. Raunser and colleagues used cryo-electron microscopy (cryo-EM) to obtain the structures of the protein in the open and in the closed states and compared them with structures of the human proteins that are already known. “The difference between human and insect channels are really tiny, but we found protein regions that are specific to insects,” says Raunser.
Detailed map of the potassium channel for drug discovery
One specific site of the channel, named RCK2 pocket, has amino acids that differ between Drosophila and humans. It is located at the gating ring at the bottom of the channel. The gating ring sits inside the cell, picks up calcium ions when abundant and kicks off a cascade of rearrangements that open up the central cavity for potassium ions to pass through. The RCK2 pocket changes its shape as it shifts between closed and open states. Therefore, it is a potentially perfect target for small molecules to block the channel in either state. Scientists pinpointed also other less insect-specific drug target sites. Among them, the S6 pocket appears in the closed state and could be used to lock the channel. “We are providing pharmaceutical scientists with a detailed map of the potassium channel, which they can use to make better, highly selective insecticides,” concludes Raunser.
Additionally, the researchers also solved the cryo-EM structures of the channel with two known compounds, verruculogen and emodepside. The fungal neurotoxin verruculogen is a small molecule that fits perfectly in the S6 pocket, close to the central cavity. Verruculogen keeps the channel narrow, locking it in the closed state. Another compound, emodepside, a drug used against gastrointestinal worms in cats and dogs, also binds close to the S6 pocket. Yet, it acts differently, as an additional passing filter, making it difficult for potassium to go through the channel in an optimal way. “It’s important to understand how these ligands can manipulate the channel,” says Raunser.
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With the federal requirement in limbo because of legal challenges, some major multistate hospital systems have stopped enforcing their own policies.The legal uncertainty over a federal requirement that the nation’s 17 million health care workers be vaccinated against the coronavirus has led some well-known hospital chains to drop their own mandates — at least temporarily.The Cleveland Clinic, HCA Healthcare and Intermountain Healthcare, among others, have said they are no longer requiring employees to be vaccinated until the courts sort out whether the federal mandate can go into effect. The hospitals’ decisions were first reported by The Wall Street Journal.The moves are likely to slow down efforts to quell the latest surge in infections, potentially worsening by holiday traveling, large gatherings indoors and the introduction of the Omicron variant. Public health officials are renewing their pleas for more people to get vaccinations and booster shots as this latest wave of Covid cases threatens to again overwhelm hospitals. Some 66,000 Americans are now hospitalized with Covid.Suspending the localized requirements will also make it harder for hospitals to meet the federal government’s deadline of early January for vaccinating all eligible staff if the courts uphold the mandate. Federal officials are appealing a Louisiana judge’s decision to halt the rule, and the case is likely to go to the Supreme Court. The court on Monday allowed New York State’s vaccine requirement for health care workers to continue, and the justices have previously rejected challenges to other vaccine requirements.Exactly how many hospitals are abandoning the policy is unclear. Many states, like California and New York, and local governments, like Philadelphia’s, adopted their own edicts. HCA specified that it would continue the requirement at hospitals in places where there is a state mandate.Several large hospital groups imposed their own requirements earlier this year after experiencing a sharp rise in cases from the Delta variant. About 40 percent of the nation’s hospitals mandated vaccinations for staff members, and the Centers for Medicaid and Medicare Services, which issued the new rule, says many facilities have already succeeded in getting workers protected.Decisions on enforcement “have varied across the board,” said Erin J. McLaughlin, a labor and employment lawyer for Buchanan, Ingersoll & Rooney. She said an equal number of her health care clients had scrapped the requirement as had continued it.An I.C.U. pharmacist at St. Peter’s Health in Helena, Mont., received a shot. About 40 percent of the nation’s hospitals mandated vaccinations for staff members, but some have now suspended enforcing their policies. Thom Bridge/Independent Record, via The Associated Press“We do not think most hospitals are changing their mandates,” the American Hospital Association, a trade group, said in a statement. “While the current C.M.S. vaccine requirement may be delayed, hospitals and health systems are not delaying their efforts to vaccinate staff,” the group said.But the legal landscape is confusing at best, with states and local governments often running counter to the federal efforts. In Florida, where AdventHealth, HCA and UF Health Jacksonville have all paused their requirements, Gov. Ron DeSantis prohibited vaccine mandates by private employers shortly after the federal government issued its rule for health care workers.Exactly how many health care workers still need to get vaccinated is also unclear. While a study by federal researchers found that 30 percent of hospital workers were not fully vaccinated as of mid-September, overall immunization rates have climbed in the last few months. HCA, which employs about 275,000 workers and operates in 20 states, said most of its workers were fully vaccinated, but it would not provide specifics. Neither AdventHealth nor UF Health Jacksonville would say how many of its employees were vaccinated. Unlike nursing homes, hospitals are not required to publicly report their vaccination rates.But many hospitals insist they are continuing efforts to persuade workers. “Based on scientific evidence and what we see in our hospitals every day, Covid-19 vaccines are safe and effective at reducing both the risk of becoming infected and the level of harm in the case of a breakthrough infection,” AdventHealth said in a statement.Hospitals “are totally committed to having their work force vaxxed,” said Chip Kahn, the chief executive of the Federation of American Hospitals, which represents for-profit chains like HCA.Much of the opposition to the requirements is over concerns that workers who object to the vaccine will leave. Many hospital chains said departures had not been numerous, but Mr. Kahn emphasized that even a small number of resignations can be disruptive. “Those small numbers can really be a problem,” he said.Some hospital companies said they would pursue alternatives to keep patients and employees safe. The Cleveland Clinic, which estimated that nearly 85 percent of its employees were fully vaccinated, said it was adding more measures, “including periodic testing for those providing direct clinical care.”Hospitals that do not want to insist on immunizations are focusing on testing their employees, said Ann Marie Pettis, the president of the Association for Professionals in Infection Control and Epidemiology, which supports a mandate for health care workers. “It’s not like they are just throwing up their hands and saying it is a free-for-all,” she said.Other hospitals already have high numbers of vaccinated workers. Intermountain, along with other Utah hospitals, is pausing its requirement and said 98 percent of its staff was already vaccinated.

Case reports of relatively young COVID-19 patients who developed Parkinson’s disease within weeks of contracting the virus have led scientists to wonder if there could be a link between the two conditions. Now, researchers reporting in ACS Chemical Neuroscience have shown that, at least in the test tube, the SARS-CoV-2 N-protein interacts with a neuronal protein called α-synuclein and speeds the formation of amyloid fibrils, pathological protein bundles that have been implicated in Parkinson’s disease.
In addition to respiratory symptoms, SARS-CoV-2 can cause neurological problems, such as loss of smell, headaches and “brain fog.” However, whether these symptoms are caused by the virus entering the brain, or whether the symptoms are instead caused by chemical signals released in the brain by the immune system in response to the virus, is still controversial. In Parkinson’s disease, a protein called α-synuclein forms abnormal amyloid fibrils, leading to the death of dopamine-producing neurons in the brain. Interestingly, loss of smell is a common premotor symptom in Parkinson’s disease. This fact, as well as case reports of Parkinson’s in COVID-19 patients, made Christian Blum, Mireille Claessens and colleagues wonder whether protein components of SARS-CoV-2 could trigger the aggregation of α-synuclein into amyloid. They chose to study the two most abundant proteins of the virus: the spike (S-) protein that helps SARS-CoV-2 enter cells, and the nucleocapsid (N-) protein that encapsulates the RNA genome inside the virus.
In test tube experiments, the researchers used a fluorescent probe that binds amyloid fibrils to show that, in the absence of the coronavirus proteins, α-synuclein required more than 240 hours to aggregate into fibrils. Adding the S-protein had no effect, but the N-protein decreased the aggregation time to less than 24 hours. In other experiments, the team showed that the N- and α-synuclein proteins interact directly, in part through their opposite electrostatic charges, with at least 3-4 copies of α-synuclein bound to each N-protein. Next, the researchers injected N-protein and fluorescently labeled α-synuclein into a cell model of Parkinson’s disease, using a similar concentration of N-protein as would be expected inside a SARS-CoV-2-infected cell. Compared to control cells with only α-synuclein injected, about twice as many cells died upon injection of both proteins. Also, the distribution of α-synuclein was altered in cells co-injected with both proteins, and elongated structures were observed, although the researchers could not confirm that they were amyloid. It’s unknown whether these interactions also occur within neurons of the human brain, but if so, they could help explain the possible link between COVID-19 infection and Parkinson’s disease, the researchers say.
The authors acknowledge funding from Stichting ParkinsonFonds.
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The percentage of obese children and teens jumped from 19% pre-pandemic to 22%, according to a study from the Centers for Disease Control and Prevention. And the rate at which body mass index (BMI) increased doubled.
New research from the University of Georgia suggests that could spell bad news for children’s cardiovascular systems both now and down the line.
Published in Pediatric Obesity, the study measured abdominal visceral fat levels and arterial stiffness in more than 600 children, adolescents and young adults. Visceral fat is the fat found in the abdomen that infiltrates vital organs. Arterial stiffness forces the cardiovascular system to work harder to pump blood throughout the body.
The researchers found significantly higher levels of visceral fat and arterial stiffness in the overweight youth, suggesting that abdominal fat likely contributes to cardiovascular problems in kids.
“The stiffer the artery, the faster blood is going to move through those blood vessels, and that can be detrimental and overstress our system,” said Joseph Kindler, corresponding author of the study and an assistant professor of nutritional sciences in the College of Family and Consumer Sciences. “As these issues build up, unfortunately, it’s sort of this game of dominoes. You tip one over, and the rest of the systems start being overtaxed. That’s when really pervasive health issues can occur.”
Studies of cardiovascular risks in youth are limited, but researchers believe the negative changes to the cardiovascular system that lead to disease and heart attacks likely begin in childhood and adolescence.

With numerous recent studies demonstrating that antibiotics work as well as surgery for most uncomplicated appendicitis cases, the non-surgical approach can now be considered a routine option, according to a review article in JAMA.
The finding — appearing Dec. 14 and led by Theodore Pappas, M.D., professor in the Department of Surgery at Duke University School of Medicine — cites the consensus of evidence that antibiotics successfully treat up to 70% of appendicitis cases. Surgery, usually done laparoscopically, remains the definitive option for otherwise healthy patients with a severely inflamed appendix or other factors that increase the risk of rupture.
“Acute appendicitis is the most common abdominal surgical emergency in the world, striking about one in 1,000 adults,” Pappas said. “Until recently, the only treatment option was surgery, so having a non-surgical approach for many of these cases has significant impact for both patients and the health care system.”
Pappas said the criteria for determining the best treatment approach is nuanced, but not excessively difficult. Appendicitis cases — marked by abdominal pain that often migrates to the lower right side, nausea and vomiting, and low-grade fever — are confirmed with ultrasound and/or CT scans.
If the scans depict no complications, most of these patients could receive antibiotics instead of undergoing an appendectomy. Antibiotics could also be a first-line therapy for patients who have severe symptoms, but who are older or have medical conditions that add risks to surgeries.
“We think it’s going to be 60% to 70% of patients who are good candidates for consideration of antibiotics,” Pappas said. “A lot of people note that patient preferences can be brought into the decision, so it is important to provide the literature and educate the public.”
Pappas added that antibiotics are not always a complete cure. In about 40% of cases, patients who recover from a bout of appendicitis after receiving antibiotics have another episode and eventually need their appendix surgically removed.
“It’s important to take into account every case and it’s unique context as we consider patient preferences,” Pappas said. “If someone presents with an appendicitis and they’re attending their brother’s wedding the next day, antibiotics may be a good option. If they have appendicitis and they are planning to head to rural Alaska next year, they might want to consider an appendectomy, given that the condition could recur.”
In addition to Pappas, study authors are Dimitrios Moris, a Duke surgical resident, and Erik K. Paulson, chair of the Department of Radiology at Duke.
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Patients with colorectal cancer were among the first to receive targeted therapies. These drugs aim to block the cancer-causing proteins that trigger out-of-control cell growth while sparing healthy tissues. But some patients are not eligible for these treatments because they have cancer-promoting mutations that are believed to cause resistance to these drugs.
Now, Salk Assistant Professor and physician-scientist Edward Stites has used computer modeling and cell studies to discover that more patients may be helped by a common class of targeted therapies than previously thought. The findings were published December 14, 2021, in Cell Reports.
“Colorectal cancer patients who have tried all of the standard treatment options but still seen their cancer progress are in need of new options. Our study suggests that one already available targeted therapy could benefit up to 12,000 additional colon cancer patients every year,” says Stites, the paper’s senior author. “Our findings are pre-clinical, and we hope this research will motivate clinicians to develop clinical trials that further examine our results.”
Stites was interested in examining drugs that target a protein called EGFR (epidermal growth factor receptor). EGFR is known to drive a subset of a number of different cancer types, including lung cancer and colorectal cancer.
In 2004, the US Food and Drug Administration (FDA) approved cetuximab, the first drug to block EGFR activity in colorectal cancer. Since then, other drugs that target EGFR also have received approval. But from the early development of these drugs, doctors believed that patients with a mutation in any one of the family of proteins known as RAS would not respond to EGFR drugs. Therefore, whenever molecular testing of a patient’s tumor revealed a RAS mutation, the patient was not offered these targeted therapies.
Earlier research by the Stites lab suggested that not all RAS mutations act in the same manner, and was able to explain one well-known, but poorly understood, exception to the rule. In the new study, the team combined computational and experimental approaches to use this new explanation to find more RAS mutations that should not cause resistance to the EGFR drugs.
The researchers used cells from cancers that were identical except for specific RAS mutations. This allowed them to compare how each specific mutation influenced the response to EGFR-inhibiting drugs. They found that some RAS mutations did not prevent the drugs from working. These experiments also allowed them to validate their computational studies, which helps establish how new computational methods could contribute to improving treatment options for cancer patients.
The investigators also examined how well different RAS mutants bound to another protein, called NF1. Stites’ previous mathematical models hinted that NF1 could play a key role in the cells’ response to targeted drugs. In their new studies they revealed that the RAS mutants that do not bind NF1 well retain sensitivity to EGFR drugs, while the RAS mutants that bind NF1 well are resistant to EGFR drugs. This relationship to EGFR drugs was not originally apparent, but the computational modeling was able to uncover it from within the available and varied data.
Ultimately, the investigators identified 10 distinct RAS mutations that do not preclude the use of EGFR inhibitors. Many of the drugs that would work for these mutations are already approved by the FDA for other uses, which means that doctors could start prescribing them for their patients “off label” even before clinical trials are conducted.
Stites, who holds the Hearst Foundation Developmental Chair, stresses that this study also helps to validate the mathematical and computational methods developed by his team. “Models can solve scientific problems that traditional methods cannot,” he says. “We hope that future clinical trials will help identify the magnitude of benefit as well as whether all the RAS mutations we identified are equally sensitive to the EGFR-inhibiting drugs and how other mutations in addition to RAS may influence the strength of the response.”
The first author of the paper is Thomas McFall, a former postdoctoral fellow at Salk who is now at the Medical College of Wisconsin.
This work was supported by National Institutes of Health grants K22CA216318, DP2AT011327, T32CA009370 and P30CA014195 and Department of Defense grant W81XWH-20-1-0538.
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Efforts to eradicate a human parasitic disease are being hampered by dogs eating infected fish, new research shows.
Guinea worm disease is usually caught by drinking water containing water fleas that carry the parasite larvae.
The worms mate and grow inside the body, and after 10-14 months the one-metre-long adult worm emerges, usually from the arms or legs, to shed its larvae back into water.
The parasite causes disability and trauma in some of the world’s poorest communities in Chad, Ethiopia, Mali and South Sudan.
Eradication programmes have cut human cases of Guinea worm from millions a year in the 1980s to just 27 in 2020.
Guinea worm would be only the second human disease to be eradicated, after smallpox.

The number of cases of tick-borne illnesses (TBIs) reported annually to the Centers for Disease Control and Prevention (CDC) has more than doubled over the past two decades in the United States. An expert panel has developed a set of clinical practice guidelines that recommends low-risk interventions, employable with minimal resources, to help reduce the number of TBIs. The guidelines, issued by the Wilderness Medical Society, appear in Wilderness & Environmental Medicine, published by Elsevier.
Although Lyme disease is the most commonly reported vector-borne disease in the United States, the incidence of other TBIs, including anaplasmosis, spotted fever rickettsiosis, babesiosis, tularemia, alpha-gal syndrome, and Powassan virus, continues to rise as well. Lyme disease accounted for nearly 70% of cases of TBI reported in 2019, anaplasmosis 16%, and spotted fever rickettsiosis 10%. Experts believe that formal reporting probably underestimates the disease burden.
“TBI is influenced by the environment, geography, climate, ecology, and animal and human behavior,” explained lead author Benjamin M. Ho, MD, Southern Wisconsin Emergency Associates, Janesville, WI, USA. “It cannot be completely avoided given the interactions between humans and the environment. However, the overall burden of disease related to TBIs can be reduced with certain behavioral and medical adaptations.”
The Wilderness Medical Society convened an expert panel to develop evidence-based guidelines for the prevention and management of TBI. The guidelines include a brief review of the clinical presentation, epidemiology, prevention, and management of TBIs in the United States, with a primary focus on interventions that are appropriate for resource-limited settings. Their recommendations are largely consistent with those presented by the CDC and other practice guidelines, but they specifically highlight concepts most relevant to providers who encounter ticks in backcountry, austere, and limited-resource settings.
Clinical practice guidelines include: Wear long-sleeved clothing when traveling in tick habitat. Light-colored clothing may not reduce the risk of tick bites but makes it easier to identify ticks on clothes during tick checks. N-diethyl-meta-toluamide (DEET) is an effective tick repellent. It can be used in children over the age of two months. The efficacy of picaridin compares favorably to DEET. It may have a superior safety profile when compared to DEET. Permethrin-treated clothing may further reduce the risk of TBI when used in combination with a skin-based tick repellent such as DEET or picaridin. Avoid essential oils, citriodiol, nootkatone, and IR3535 as a first line repellent as they have either a lower repellent efficacy or significantly shorter duration of action. Evidence supporting tick checks is contradictory but may help prevent TBI when combined with showering or bathing within two hours of returning from tick habitat. Washing clothes at temperatures over 54°C/130°F and drying clothing in high heat for ten minutes kills ticks and may reduce the risk of TBIs. When feasible, avoid areas with high grass or leaf litter. When in tick habitat, walk in the middle of trails to reduce the chance of contact with ticks. Mechanical removal by pulling upward, or perpendicular to skin with forceps, directly on an embedded tick, is the best currently available method. Commercial devices may also work, but there is no evidence suggesting they are superior. Pulling embedded ticks with straight, steady pressure is preferred over a twisting movement. Chemical strategies that involve exposing attached ticks to petroleum jelly, fingernail polish, isopropyl alcohol, gasoline, or methylated spirits are ineffective and not recommended. There is no evidence that using local or systemic medications such as locally infiltrated anesthetics or systemic ivermectin is effective in removing or exterminating attached ticks. Remove ticks as soon as possible. To meaningfully reduce the risk of Lyme disease, ticks should be removed within 36 hours. A single dose of 200 mg doxycycline orally is recommended after a high-risk tick bite to reduce the risk of Lyme disease if given within 72 hours. Outside of high-risk Lyme disease exposures, prophylactic antibiotics are not indicated. Individuals who develop systemic or high-risk symptoms (fever, generalized rash, arthralgias, cranial nerve palsy, dyspnea, or syncope) related to a suspected TBI should be evacuated to a higher level of medical care. Individuals who develop symptoms suggestive of Lyme carditis such as dyspnea, dizziness, or syncope should receive a screening ECG as soon as possible and would benefit from a thorough cardiovascular evaluation in an appropriate clinical setting. Although no vaccine for tick-borne encephalitis is currently available in the United States, vaccines such as Encepur appear to be efficacious for inducing seroconversion against tick-borne encephalitis. Educational programs should be encouraged as these can change behavior and lower rates of TBI.”With a changing climate that continues to influence the epidemiology of TBI, promotion and strict adherence to simple prevention measures is important,” commented Dr. Ho. “Despite the limitations of the existing literature, these guidelines provide a starting point for front-line providers to mitigate the transmission and reduce the disease burden of TBIs through education and low-risk interventions.”
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A trial has begun of a new needle-free Covid-19 vaccine to protect against future variants of the virus.The vaccine, administered through a jet of air, has been developed by Prof Jonathan Heeney of Cambridge University and chief executive of DIOSynVax.As well as being useful for people with a fear of needles, the vaccine can be freeze-dried, making it easier to store. Participants began taking part in the trial at the NIHR Southampton Clinical Research Facility on Tuesday.Demonstrating the vaccine earlier this year, Dr Rebecca Kinsley from DIOSynVax said: “There’s no needle or hole. It uses a high-powered jet stream, which allows the vaccine to pass through the layer of skin.”Find BBC News: East of England on Facebook, Instagram and Twitter. If you have a story suggestion email eastofenglandnews@bbc.co.uk

An immunotherapy harnessing the immune system’s “natural killer” cells has proven effective in treating acute myeloid leukemia (AML) in some adults whose cancers return. Now, researchers at Washington University School of Medicine in St. Louis have shown, in a small clinical trial, that the same natural killer cells also can help some children and young adults with recurrent AML and few other treatment options.
Results from the phase 1 trial, which included eight patients ages 1 to 30 years, are published online in the journal Blood.
“All of the patients enrolled in this study had very aggressive AML,” said first author Jeffrey J. Bednarski, MD, PhD, an assistant professor of pediatrics. “For all of them, their leukemia recurred after stem cell transplantation and was not responsive to several treatment regimens before they were referred to this study. This is a very challenging disease to treat — none of the patients had any curative options. The survival expectation for these patients was essentially zero. That three patients are still alive is very encouraging for this really challenging disease.”
Acute myeloid leukemia is a cancer of the blood and bone marrow that results in the overproduction of immature white blood cells, which crowd out healthy blood cells. Standard therapy involves chemotherapy and a stem cell transplant from a donor, which can result in a long-term remission. But for patients whose cancers return after stem cell transplantation, the disease becomes extremely difficult to treat, and most patients ultimately die from progression of their disease within a few months to a year.
Of the eight patients who received the investigational treatment, four achieved complete remission by day 28 after therapy. Two of the four stayed in remission for more than three months. One of these patients remains in remission today, more than two years after the treatment. Three patients who went into remission later relapsed. Of those three, two were able to receive a second stem cell transplant, and they’re still alive and doing well. Two other patients had a partial response to the therapy, in that their disease decreased, but they did not go into remission. The remaining two patients did not respond to the therapy.
“We found that the donor’s natural killer cells expanded, persisted and remained highly active against the leukemia in most of the patients for over three months,” said Bednarski, who treats patients in the pediatric cancer program at Siteman Kids at St. Louis Children’s Hospital and Washington University School of Medicine. “This therapy also was very well tolerated by the patients, who experienced almost no toxicities.”
Natural killer cells are a type of immune cell that attacks foreign or compromised cells, including bacteria, virus-infected cells and even cancer cells. Past work from Washington University researchers has shown that natural killer cells’ ability to attack cancer cells can be enhanced by exposing them to a specific cocktail of chemicals called cytokines. The natural killer cells are collected from a donor and then exposed in the lab to three cytokines called interleukins 12, 15 and 18. This exposure activates the cells and prompts them to remember this activation. When such “cytokine-induced memory-like” natural killer cells are given to the patient, they are more aggressive in attacking the cancer because of this pre-activation.
“A unique angle to this study is that we’re using the patient’s original stem cell donor’s cells to generate the memory-like natural killer cells, so the cells won’t be rejected by the patient’s immune system but are still able to fight the leukemia,” said senior author Todd A. Fehniger, MD, PhD, a professor of medicine who treats patients at Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine. “We’re also pleased to see evidence that these cells are extremely safe. They do not have the severe side effects that are sometimes seen in cellular therapies based on T cells. Using cutting-edge science within this trial, we also now understand these memory-like natural killer cells are very unique, even compared with conventional natural killer cells.”
Fehniger’s lab developed the methods for producing the cytokine-induced memory-like natural killer cells and led the original clinical trial of these cells in adults with AML.
Based on the experience of these eight patients, the investigators are making some changes to the protocol in an effort to make the treatment more effective for future patients. Bednarski said they will combine the memory-like natural killer cells with different chemotherapies to investigate whether that can optimize the killing of leukemia cells. They also will add a second infusion of the memory-like natural killer cells to extend the amount of time that the cells have to expand in the body and kill the leukemia cells.
“We plan to treat a larger group of pediatric and adult patients using this approach in an ongoing study,” Fehniger said. “Memory-like natural killer cells also are being explored as an experimental treatment for other cancers, including solid tumors such as melanoma and head and neck cancers, which are really exciting advancements in the field.”
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Materials provided by Washington University School of Medicine. Original written by Julia Evangelou Strait. Note: Content may be edited for style and length.