Monthly Archives: October 2020
A coronavirus strain that emerged in Spain in June has spread across Europe and now makes up a large proportion of infections in several countries, researchers said, highlighting the role of travel in the pandemic and the need to track mutations. The variant, which has not been found to be inherently more dangerous, was first identified among farm workers in the eastern Spanish regions of Aragon and Catalonia.
Over the last two months, it has accounted for close to 90% of new infections in Spain, according to the research paper, authored by seven researchers with backing by Swiss and Spanish public-sector science institutions. It was posted on a so-called preprint server https://www.medrxiv.org/ and is yet to be peer reviewed for publication in a scientific journal.
Li Shurui didn’t hesitate. Faced with putting his life on hold indefinitely or the risk of catching COVID-19 by returning to university in the U.K., the 22-year-old business student decided to roll up his sleeve and receive an experimental coronavirus vaccine.
Two injections of CoronaVac made by SinoVac (otherwise known as Beijing Kexing Bioproducts) cost 2,000 rmb ($300) at the private Taihe Hospital in the Chinese capital. The treatment still hasn’t passed final (Stage 3) clinical trials but is already being offered to the public on a first come, first served basis. Anyone can turn up, pay their money and get the jab. Li says hundreds were queuing to get immunized at the same time as him.
“I’m a little worried about side effects but more worried catching the virus overseas,” says Li . “But I haven’t had any problems from the jabs so far.”
It’s not just the CoronaVac vaccine on offer in China. An unofficial vaccine rollout is gathering pace despite the warnings of international public health experts. In September, state-owned SinoPharm revealed that hundreds of thousands of Chinese had already taken its experimental COVID-19 vaccines as part of a state initiative to protect frontline health workers and officials traveling to high-risk nations. In the eastern manufacturing hub of Yiwu this week, hundreds of people queued for a $60 dose of CoronaVac.
“This is insane,” Adam Kamradt-Scott, associate professor specializing in global health security at the University of Sydney, says of China’s gung-ho vaccine rollout. “It is just unsound public health practice. We have previous examples of where vaccines that have not gone through sufficient clinical trials have demonstrated adverse reactions with long-term health consequences.”
But it’s not just China that’s getting ahead of itself. U.S. President Donald Trump has put enormous public pressure on regulators and pharmaceutical companies to make a vaccine available in time for the American election. On Oct. 16, Pfizer revealed it may begin rolling out its vaccine for emergency use in the U.S. by late November. Moderna has a similar timeline for emergency use, though cautions widespread vaccine distribution may not happen until the spring.
Scientists report that they have successfully created airway basal stem cells in vitro from induced pluripotent stem cells by reprogramming blood cells taken from patients. Given that airway basal cells are defined as stem cells of the airways because they can regenerate the airway epithelium in response to injury, this study may help accelerate research on diseases impacting the airway, including COVID-19, influenza, asthma, and cystic fibrosis, according to the team led by researchers at the Center for Regenerative Medicine at Boston Medical Center and Boston University (CReM), in collaboration with the University of Texas Health Science Center at Houston (UTHealth).
These findings represent a critical first step towards airway regeneration, which will advance the field of regenerative medicine as it relates to airway and lung diseases, added the scientists.
The study, “Derivation of Airway Basal Stem Cells from Human Pluripotent Stem Cells,” published in Cell Stem Cell, outlines how to generate and purify large quantities of airway basal stem cells using patient samples. This allows for the development of individual, disease-specific airway basal stem cells in a lab that can be used to develop disease models, which may ultimately lead to drug development and a platform in which targeted drug approaches can be tested.
The study’s findings and cells will be shared freely given the CReM’s “Open Source Biology” philosophy, or sharing of information and findings that will help advance science across the globe.
Human Airway Basal Stem Cells
“The derivation of tissue-specific stem cells from human induced pluripotent stem cells (iPSCs) would have broad reaching implications for regenerative medicine. Here, we report the directed differentiation of human iPSCs into airway basal cells (iBCs), a population resembling the stem cell of the airway epithelium,” the investigators wrote.
“Simply put, we have developed a way to reproduce patient-specific airway basal cells in the lab, with the ultimate goal of being able to regenerate the airway for patients with airway diseases,” said Finn Hawkins, MB, a pulmonologist and physician-scientist at Boston Medical Center, principal investigator in the CReM and the Pulmonary Center, and the study’s first author.
“These results could lead to a better understanding, and therefore treatments for, a variety of airway diseases,” noted Shingo Suzuki, PhD, co-first author and post-doctoral researcher at UTHealth. For example, cystic fibrosis is caused by a genetic mutation that is present in all of the airway cells. “If we could make pluripotent stem cells using a sample from a patient who has cystic fibrosis, correct the mutation and replace the defective airway cells with corrected airway basal cells that are otherwise genetically identical, we might eventually be able to cure the disease, and other diseases in the future using this same technology,” added Hawkins.
Immunogenicity responses similar between older and younger adults
One of the world’s leading COVID-19 experimental vaccines produces a immune response in both old and young adults, raising hopes of a path out of the gloom and economic destruction wrought by the novel coronavirus. The vaccine, developed by the University of Oxford, also triggers lower adverse responses among the elderly, British drug maker AstraZeneca Plc AZN.L, which is helping manufacture the vaccine, said on Monday. A vaccine that works is seen as a game-changer in the battle against the novel coronavirus, which has killed more than 1.15 million people, shuttered swathes of the global economy and turned normal life upside down for billions of people.
“It is encouraging to see immunogenicity responses were similar between older and younger adults and that reactogenicity was lower in older adults, where the COVID-19 disease severity is higher,” an AstraZeneca spokesman said.
Tiny artificial lungs grown in a lab from adult stem cells have allowed scientists to watch how coronavirus infects the lungs in a new ‘major breakthrough‘. Researchers from Duke University and Cambridge University produced artificial lungs in two independent and separate studies to examine the spread of Covid-19. The ‘living lung‘ models minimic the tiny air sacs that take up the oxygen we breathe, known to be where most serious lung damage from the deadly virus takes place. Having access to the models to test the spread of SAS-CoV-2, the virus responsible for Covid-19, will allow researchers to test potential drugs and gain a better understanding of why some people suffer from the disease worse than others.
In both studies the 3D min-lung models were grown from stem cells that repair the deepest portions of the lungs when SARS-CoV-2 attacks – known as alveolar cells. To date, there have been more than 40 million cases of COVID-19 and almost 1.13 million deaths worldwide. The main target tissues of SARS-CoV-2, especially in patients that develop pneumonia, appear to be alveoli, according to the Cambridge team. They extracted the alveoli cells from donated tissue and reprogrammed them back to their earlier ‘stem cell‘ stage and forced them to grow into self-organising alveolar-like 3D structures that mimic the behaviour of key lung tissue. Dr Joo-Hyeon Lee, co-senior author of the Cambridge paper, said we still know surprisingly little about how SARS-CoV-2 infects the lungs and causes disease.
Representative image of three – dimensional human lung alveolar organoid produced by the Cambridge and Korean researchers to better understand SARS-CoV-2
‘Our approach has allowed us to grow 3D models of key lung tissue – in a sense, “mini-lungs” – in the lab and study what happens when they become infected.’
Duke researchers took a similar approach. The team, led by Duke cell biologist Purushothama Rao Tata, say their model will allow for hundreds of experiments to be run simultaneously to screen for new drug candidates. ‘This is a versatile model system that allows us to study not only SARS-CoV-2, but any respiratory virus that targets these cells, including influenza,‘ Tata said.
Both teams infected models with a strain of SARS-CoV-2 to better understand who the virus spreads and what happens in the lung cells in response to the disease. The Cambridge team worked with researchers from South Korea to take a sample of the virus from a patient who was infected in January after travelling to Wuhan. Using a combination of fluorescence imaging and single cell genetic analysis, they were able to study how the cells responded to the virus.
When the 3D models were exposed to SARS-CoV-2, the virus began to replicate rapidly, reaching full cellular infection just six hours after infection. Replication enables the virus to spread throughout the body, infecting other cells and tissue, explained the Cambridge research team. Around the same time, the cells began to produce interferons – proteins that act as warning signals to neighbouring cells, telling them to activate their defences. After 48 hours, the interferons triggered the innate immune response – its first line of defence – and the cells started fighting back against infection. Sixty hours after infection, a subset of alveolar cells began to disintegrate, leading to cell death and damage to the lung tissue.
The US Centers for Disease Control and Prevention (CDC) has updated its definition of a close contact with a Covid-19 patient to include multiple, brief exposures, director Dr. Robert Redfield said Wednesday.
The new definition includes exposures adding up to a total of 15 minutes spent six feet or closer to an infected person. Previously, the CDC defined a close contact as 15 minutes of continuous exposure to an infected individual.
The agency changed the definition after a report from Vermont of a corrections officer who became infected after several brief interactions with coronavirus-positive inmates – none of them lasting 15 minutes, but adding up over time.
“As we get more data and understand the science of Covid, we are going to incorporate that in our recommendations,” Redfield said at a news conference held at CDC headquarters in Atlanta. “Originally, contact that was considered to be high risk for potential exposure to Covid was someone within six feet for more than 15 minutes.”
Australian-based venture LAVO, a university spin-off that has developed an innovative hydrogen-based energy storage system for homes and businesses, is one step closer to commercialisation, announcing that the technology is now ‘commercially-ready’ and will soon start taking orders for the first systems.
The LAVO system has been developed by researchers at the University of New South Wales, and uses compressed hydrogen as the main medium for energy storage. The company says that by using hydrogen, the LAVO device can offer three times the amount of energy storage compared to other devices of similar size, and offers double the operational life.
The LAVO system utilises a metal hydride material, which absorbs hydrogen that provides a safe and stable medium for storing hydrogen over the long-term.
LAVO said the system would be available for advanced purchase in November, with the first systems ready for installation in June 2021.
A rectangular robot as tiny as a few human hairs can travel throughout a colon by doing back flips, Purdue University engineers have demonstrated in live animal models. Why the back flips? Because the goal is to use these robots to transport drugs in humans, whose colons and other organs have rough terrain. Side flips work, too. Why a back-flipping robot to transport drugs? Getting a drug directly to its target site could remove side effects, such as hair loss or stomach bleeding, that the drug may otherwise cause by interacting with other organs along the way.
The study, published in the journal Micromachines, is the first demonstration of a microrobot tumbling through a biological system in vivo. Since it is too small to carry a battery, the microrobot is powered and wirelessly controlled from the outside by a magnetic field.
“When we apply a rotating external magnetic field to these robots, they rotate just like a car tire would to go over rough terrain,” said David Cappelleri, a Purdue associate professor of mechanical engineering. “The magnetic field also safely penetrates different types of mediums, which is important for using these robots in the human body.”
The researchers chose the colon for in vivo experiments because it has an easy point of entry – and it’s very messy. “Moving a robot around the colon is like using the people-walker at an airport to get to a terminal faster. Not only is the floor moving, but also the people around you,” said Luis Solorio, an assistant professor in Purdue’s Weldon School of Biomedical Engineering. “In the colon, you have all these fluids and materials that are following along the path, but the robot is moving in the opposite direction. It’s just not an easy voyage.”
But this magnetic microrobot can successfully tumble throughout the colon despite these rough conditions, the researchers’ experiments showed. The team conducted the in vivo experiments in the colons of live mice under anesthesia, inserting the microrobot in a saline solution through the rectum. They used ultrasound equipment to observe in real time how well the microrobot moved around.
Research is coalescing around the idea that people with Type O blood may have a slight advantage during this pandemic. Two studies published this week suggest that people with Type O have a lower risk of getting the coronavirus, as well as a reduced likelihood of getting severely sick if they do get infected. One of the new studies specifically found that COVID-19 patients with Type O or B blood spent less time in an intensive-care unit than their counterparts with Type A or AB. They were also less likely to require ventilation and less likely to experience kidney failure.
These new findings echo similar findings about Type O blood seen in previous research, creating a clearer picture of one particular coronavirus risk factor. Both new studies came out Wednesday in the journal Blood Advances. One looked at 95 critically ill COVID-19 patients at hospitals in Vancouver, Canada, between February and April. They found that patients with Type O or B blood spent, on average, 4.5 fewer days in the intensive-care unit than those with Type A or AB blood. The latter group stayed, on average, 13.5 days in the ICU. The researchers did not see any link between blood type and the patient’s total hospital stay, however. They did, however, find that only 61 percent of the patients with Type O or B blood required a ventilator, compared to 84 percent of patients with Type A or AB.
Patients with Type A or AB, meanwhile, were also more likely to need dialysis, a procedure that helps the kidneys filter toxins from the blood.
“Patients in these two blood groups may have an increased risk of organ dysfunction or failure due to COVID-19 than people with blood types O or B,” the study authors concluded.
A June study found a similar link: Patients in Italy and Spain with Type O blood had a 50 percent reduced risk of severe coronavirus infection (meaning they needed intubation or supplemental oxygen) compared to patients with other blood types.
The second new study found that people with Type O blood may be at a lower risk of getting he coronavirus in the first place relative to people with other blood types. The team examined nearly half a million people in the Netherlands who were tested for COVID-19 between late February and late July. Of the roughly 4,600 people who tested positive and reported their blood type, 38.4 percent had Type O blood. That’s lower than the prevalence of Type O in a population of 2.2 million Danish people, 41.7 percent, so the researchers determined that people with Type O blood had disproportionately avoided infection. “Blood group O is significantly associated with reduced susceptibility,” the authors wrote.
In general, your blood type depends on the presence or absence of proteins called A and B antigens on the surface of red blood cells – a genetic trait inherited from your parents. People with O blood have neither antigen. It’s the most common blood type: About 48 percent of Americans have Type O blood, according to the Oklahoma Blood Institute.
The new studies about blood type and coronavirus risk align with prior research on the topic. A study published in July found that people with Type O were less likely to test positive for COVID-19 than those with other blood types. An April study, too, (though it has yet to be peer-reviewed) found that among 1,559 coronavirus patients in New York City, a lower proportion than would be expected had Type O blood.
And in March, a study of more than 2,100 coronavirus patients in the Chinese cities of Wuhan and Shenzhen also found that people with Type O blood had a lower risk of infection.
Past research has also suggested that people with Type O blood were less susceptible to SARS, which shares 80 percent of its genetic code with the new coronavirus. A 2005 study in Hong Kong found that most individuals infected with SARS had non-O blood types. Despite this growing body of evidence, however, Mypinder Sekhon, a co-author of the Vancouver study, said the link is still tenuous.
“I don’t think this supersedes other risk factors of severity like age and comorbidities and so forth,” he told CNN, adding, “if one is blood group A, you don’t need to start panicking. And if you’re blood group O, you’re not free to go to the pubs and bars.”