Scientists look at how the lung and brain respond differently to SARS-CoV-2 infection

UC San Diego School of Medicine researchers found approximately 10-fold higher SARS-CoV-2 infection (green) in lung organoids (left), compared to brain organoids (right). Image courtesy of UCSD Health

Since the start of the coronavirus pandemic early last year, scientists all over the world are still trying to better understand SARS-CoV-2, the virus that causes COVID-19. Although the more commonly known symptoms involve respiratory issues, there have been other long term problems observed in recovered patients. These consist of heart issues, fatigue, and neurological issues such as loss of taste and smell and “brain fog”.

To better understand this, Dr. Tariq Rana and a team of researchers at the UC San Diego School of Medicine are using stem cells to create lung and brain organoids to better understand how the virus interacts with the various organ systems and to better develop therapies that block infection. Organoids are 3D models made of cells that can be used to analyze certain features of the human organ being modeled. Although they are far from perfect replicas, they can be used to study physical structure and other characteristics. 

The team’s lung and brain organoids produced molecules ACE2 and TMPRSS2, which sit like doorknobs on the outer surfaces of cells. SARS-CoV-2 is able to use these doorknobs to enter cells and establish infection.

Dr. Rana and his team then developed a pseudovirus, a noninfectious version of SARS-CoV-2, and attached a fluorescent label, allowing them to measure how effectively the virus binds in human lung and brain organoids as well as to evaluate the cells’ response. The team was surprised to see an approximately 10-fold higher SARS-CoV-2 infection in lung organoids compared to brain organoids. Additionally, treatment with TMPRSS2 inhibitors reduced infection levels in both organoids.

Besides differences in infection levels, the lung and brain organoids also differed in their responses to the virus. Infected lung organoids pumped out molecules intended to summon help from the immune system while infected brain organoids upped their production of molecules that plays a fundamental role in pathogen recognition and activation of the body’s own immune defenses.

In a news release from UC San Diego Health, Dr. Rana elaborates on the results of his study.

“We’re finding that SARS-CoV-2 doesn’t infect the entire body in the same way. In different cell types, the virus triggers the expression of different genes, and we see different outcomes.”

The next steps for Rana and his team is to develop SARS-CoV-2 inhibitors and test out how well they work in organoid models derived from people of a variety of racial and ethnic backgrounds that represent California’s diverse population. To carry out this research, CIRM awarded Dr. Rana a grant of $250,000, which is part of the $5 million in emergency funding for COVID-19 research that CIRM authorized at the beginning of the pandemic.

The full results of this study can be found in Stem Cell Reports.

Everything you wanted to know about COVID vaccines but never got a chance to ask

All this month we are using our blog and social media to highlight a new chapter in CIRM’s life, thanks to the voters approving Proposition 14. We are looking back at what we have done since we were created in 2004, and also looking forward to the future. Today we feature a rare treat, an interview with Moderna’s Dr. Derrick Rossi.

Moderna co-founder Dr. Derrick Rossi

It’s not often you get a chance to sit down with one of the key figures in the fight against the coronavirus and get to pick his brain about the best ways to beat it. We were fortunate enough to do that on Wednesday, talking to Dr. Derrick Rossi, the co-founder of Moderna, about the vaccine his company has developed.

CIRM’s President and CEO, Dr. Maria Millan, was able to chat to Dr. Rossi for one hour about his background (he got support from CIRM in his early post-doctoral research at Stanford) and how he and his colleagues were able to develop the COVID-19 vaccine, how the vaccine works, how effective it is, how it performs against new variations of the virus.

He also told us what he would have become if this science job hadn’t worked out.

All in all it was a fascinating conversation with someone whose work is offering a sense of hope for millions of people around the world.

If you missed it first time around you can watch it here.

How a CIRM scholar helped create a life-saving COVID vaccine

Dr. Derrick Rossi might be the most famous man whose name you don’t recognize. Dr. Rossi is the co-founder of Moderna. Yes, that Moderna. The COVID-19 vaccine Moderna. The vaccine that in clinical trials proved to be around 95 percent effective against the coronavirus.

Dr. Rossi also has another claim to fame. He is a former CIRM scholar. He did some of his early research, with our support, in the lab of Stanford’s Dr. Irv Weissman.

So how do you go from a lowly post doc doing research in what, at the time, was considered a rather obscure scientific field, to creating a company that has become the focus of the hopes of millions of people around the world?  Well, join us on Wednesday, January 27th at 9am (PST) to find out.

CIRM’s President and CEO, Dr. Maria Millan, will hold a live conversation with Dr. Rossi and we want you to be part of it. You can join us to listen in, and even post questions for Dr. Rossi to answer. Think of the name dropping credentials you’ll get when say to your friends; “Well, I asked Dr. Rossi about that and he told me…..”

Being part of the conversation is as simple as clicking on this link:

After registering, you will receive a confirmation email containing information about joining the webinar.

We look forward to seeing you there.

Month of CIRM: Battling COVID-19

All this month we are using our blog and social media to highlight a new chapter in CIRM’s life, thanks to the people of California approving Proposition 14. We are looking back at what we have done since we were created in 2004, and also looking forward to the future.

Dr. John Zaia, City of Hope stem cell researcher

The news that effective vaccines have been developed to help fight COVID-19 was a truly bright spot at the end of a very dark year. But it will be months, in some countries years, before we have enough vaccines to protect everyone. That’s why it’s so important to keep pushing for more effective ways to help people who get infected with the virus.

One of those ways is in a clinical study that CIRM is funding with City of Hope’s Dr. John Zaia. Dr. Zaia and his team, in partnership with the Translational Genomics Research Institute (TGen) in Flagstaff, Arizona, are using something called convalescent plasma to try and help people who have contracted the virus. Here’s the website they have created for the study.

Plasma is a part of our blood that carries proteins, called antibodies, that help defend our bodies against viral infections. When a patient recovers from COVID-19, their blood plasma contains antibodies against the virus. The hope is that those antibodies can now be used as a potential treatment for COVID-19 to help people who are newly infected. 

To carry out the study they are using clinical trial sites around California, including some of the CIRM Alpha Stem Cell Network clinics.

For the study to succeed they’ll first need people who have recovered from the virus to donate blood. That’s particularly appropriate in January because this is National Volunteer Blood Donor Month.

The team has three elements to their approach:

  • A rapid-response screening program to screen potential COVID-19 convalescent plasma donors, particularly in underserved communities.
  • A laboratory center that can analyze the anti-SARS-CoV-2 antibodies properties in COVID-19 convalescent plasma.
  • An analysis of the clinical course of the disease in COVID-19 patients to identify whether antibody properties correlate with clinical benefit of COVID-19 convalescent plasma.

There’s reason to believe this approach might work. A study published this week in the New England Journal of Medicine, found that blood plasma from people who have recovered from COVID-19 can help older adults and prevent them from getting seriously ill with the virus if they get the plasma within a few days of becoming infected.

We are used to thinking of blood donations as being used to help people after surgery or who have been in an accident. In this study the donations serve another purpose, but one that is no less important. The World Health Organization describes blood as “the most precious gift that anyone can give to another person — the gift of life. A decision to donate your blood can save a life, or even several if your blood is separated into its components — red cells, platelets and plasma.”

That plasma could help in developing more effective treatments against the virus. Because until we have enough vaccines for everyone, we are still going to need as much help as we can get in fighting COVID-19. The recent surge in cases throughout the US and Europe are a reminder that this virus is far from under control. We have already lost far too many people. So, if you have recently recovered from the virus, or know someone who has, consider donating blood to this study. It could prove to be a lifesaver.

For more information about the study and how you can be part of it, click here.

UCLA scientists discover how SARS-CoV-2 causes multiple organ failure in mice

Heart muscle cells in an uninfected mouse (left) and a mouse infected with SARS-CoV-2 (right) with mitochondria seen in pink. The disorganization of the cells and mitochondria in the image at right is associated with irregular heartbeat and death.
Image credit: UCLA Broad Stem Cell Center

As the worldwide coronavirus pandemic rages on, scientists are trying to better understand SARS-CoV-2, the virus that causes COVID-19, and the effects that it may have beyond those most commonly observed in the lungs. A CIRM-funded project at UCLA, co-led by Vaithilingaraja Arumugaswami, Ph.D. and Arjun Deb, M.D. discovered that SARS-CoV-2 can cause organ failure in the heart, kidney, spleen, and other vital organs of mice.

Mouse models are used to better understand the effects that a disease can have on humans. SARS-CoV-2 relies on a protein named ACE2 to infect humans. However, the virus doesn’t recognize the mouse version of the ACE2 protein, so healthy mice exposed to the SARS-CoV-2 virus don’t get sick.

To address this, past experiments by other research teams have genetically engineered mice to have the human version of the ACE2 protein in their lungs. These teams then infected the mice, through the nose, with the SARS-CoV-2 virus. Although this process led to viral infection in the mice and caused pneumonia, they don’t get as broad a range of other symptoms as humans do.

Previous research in humans has suggested that SARS-CoV-2 can circulate through the bloodstream to reach multiple organs. To evaluate this further, the UCLA researchers genetically engineered mice to have the human version of the ACE2 protein in the heart and other vital organs. They then infected half of the mice by injecting SARS-CoV-2 into their bloodstreams and compared them to mice that were not infected. The UCLA team tracked overall health and analyzed how levels of certain genes and proteins in the mice changed.

Within seven days, all of the mice infected with the virus had stopped eating, were completely inactive, and had lost an average of about 20% of their body weight. The genetically engineered mice that had not been infected with the virus did not lose a significant amount of weight. Furthermore, the infected mice had altered levels of immune cells, swelling of the heart tissue, and deterioration of the spleen. All of these are symptoms that have been observed in people who are critically ill with COVID-19.

What’s even more surprising is that the UCLA team also found that genes that help cells generate energy were shut off in the heart, kidney, spleen and lungs of the infected mice. The study also revealed that some changes were long-lasting throughout the organs in mice with SARS-CoV-2. Not only were genes turned off in some cells, the virus made epigenetic changes, which are chemical alterations to the structure of DNA that can cause more lasting effects. This might help explain why some people that have contracted COVID-19 have symptoms for weeks or months after they no longer have traces of the virus in their body.

In a UCLA press release, Dr. Deb discusses the importance and significance of their findings.

“This mouse model is a really powerful tool for studying SARS-CoV-2 in a living system. Understanding how this virus can hijack our cells might eventually lead to new ways to prevent or treat the organ failure that can accompany COVID-19 in humans.”

The full results of this study were published in JCI Insight.

You can’t take it if you don’t make it

Biomedical specialist Mamadou Dialio at work in the Cedars-Sinai Biomanufacturing Center. Photo by Cedars-Sinai.

Following the race to develop a vaccine for COVID-19 has been a crash course in learning how complicated creating a new therapy is. It’s not just the science involved, but the logistics. Coming up with a vaccine that is both safe and effective is difficult enough, but then how do you make enough doses of it to treat hundreds of millions of people around the world?

That’s a familiar problem for stem cell researchers. As they develop their products they are often able to make enough cells in their own labs. But as they move into clinical trials where they are testing those cells in more and more people, they need to find a new way to make more cells. And, of course, they need to plan ahead, hoping the therapy is approved by the Food and Drug Administration, so they will need to be able to manufacture enough doses to meet the increased demand.

We saw proof of that planning ahead this week with the news that Cedars-Sinai Medical Center in Los Angeles has opened up a new Biomanufacturing Center.

Dr. Clive Svendsen, executive director of the Cedars-Sinai Board of Governors Regenerative Medicine Institute, said in a news release, the Center will manufacture the next generation of drugs and regenerative medicine therapies.

“The Cedars-Sinai Biomanufacturing Center leverages our world-class stem-cell expertise, which already serves scores of clients, to provide a much-needed biomanufacturing facility in Southern California. It is revolutionary by virtue of elevating regenerative medicine and its therapeutic possibilities to an entirely new level-repairing the human body.”

This is no ordinary manufacturing plant. The Center features nine “clean rooms” that are kept free from dust and other contaminants. Everyone working there has to wear protective suits and masks to ensure they don’t bring anything into the clean rooms.

The Center will specialize in manufacturing induced pluripotent stem cells, or iPSCs. Dhruv Sareen, PhD, executive director of the Biolmanufacturing Center, says iPSCs are cells that can be turned into any other kind of cell in the body.

“IPSCs are powerful tools for understanding human disease and developing therapies. These cells enable us to truly practice precision medicine by developing drug treatments tailored to the individual patient or groups of patients with similar genetic profiles.”

The Biomanufacturing Center is designed to address a critical bottleneck in bringing cell- and gene-based therapies to the clinic. After all, developing a therapy is great, but it’s only half the job. Making enough of it to help the people who need it is the other half.

CIRM is funding Dr. Svendsen’s work in developing therapies for ALS and other diseases and disorders.  

CIRM-funded study shows how cigarette smoke can worsen COVID-19 infection in the airways

Microscopic images of human stem cell–derived airway tissue models with cell nuclei (blue) and SARS-CoV-2 virus infected cells (green); tissue exposed to cigarette smoke (right) had 2 to 3 times more infected cells than non-exposed tissue (left).
Image Credit: UCLA Broad Stem Cell Research Center/Cell Stem Cell

In the middle of a pandemic, stress can run really high and you might be tempted to light up a cigarette to decompress from the world around you. However, a CIRM-funded study revealed that you might want to think twice before lighting up.

It is already known that cigarette smoke is one of the most common causes of lung diseases, including lung cancer, but Dr. Brigitte Gomperts and Vaithilingaraja Arumugaswami at UCLA have pinpointed how smoking cigarettes may worsen infection by SARS-CoV-2, the virus that causes COVID-19, in the airways of the lungs.

The team used airway stem cells from the lungs of healthy non-smoking donors to create a tissue model that replicates the way that airways behave and function in humans. The researchers then exposed these newly created airways to cigarette smoke to mimic the effects of smoking.

Next, the team infected the airway tissue exposed with cigarette smoke with SARS-CoV-2 and also infected tissue not exposed to cigarette smoke. In the tissue model exposed to smoke, the researchers saw between two and three times more infected cells.

The UCLA team determined that smoking resulted in more severe SARS-CoV-2 infection. This was due to the smoke blocking the activity of immune system messenger proteins called interferons, which play an important role in the body’s early immune response. They trigger infected cells to produce proteins to attack the virus, summon additional support from the immune system, and alert uninfected cells to prepare to fight the virus. Cigarette smoke is known to reduce the interferon response in the airways.

In a UCLA news release, Dr. Gomperts explains the results with a simple analogy.

“If you think of the airways like the high walls that protect a castle, smoking cigarettes is like creating holes in these walls. Smoking reduces the natural defenses and that allows the virus to set in.” 

The hope is that these findings will help researchers better understand COVID-19 risks for smokers and could inform the development of new therapeutic strategies to help reduce smokers’ chances of developing severe disease.

The full results to this study were published in Cell Stem Cell.

One shot, two benefits!

Doctor preparing an influenza vaccine for a patient.

To try and boost sales during the pandemic many businesses are offering two-for-one deals; buy one product get another free. Well, that might also be the case with a flu shot; get one jab and get protection from two viruses.

A new study offers an intriguing – though not yet certain – suggestion that getting a flu shot could not only reduce your risk of getting the flu, but also help reduce your risk of contracting the coronavirus. If it’s true it would be a wonderful tool for health professionals hoping to head of a twindemic of flu and COVID-19 this winter. It would also be a pretty sweet deal for the rest of us.

Researchers at Radboud University Medical Center in the Netherlands looked through their hospital’s database and compared people who got a flu shot during the previous year with people who didn’t. They found that people who got the vaccine were 39 percent less likely to have tested positive for the coronavirus than people who didn’t get the vaccine.

Now, there are a bunch of caveats about this study (published in the preprint journal MedRxiv) one of which is that it wasn’t peer reviewed. Another is that people who get flu shots might just be more health conscious than people who don’t, which means they might also be more aware of the need to wear a mask, social distance, wash their hands etc.

But that doesn’t mean this study is wrong. Two recent studies (in the journal Vaccines and the Journal of Medical Virology) also found similar findings, that people over the age of 65 who got a flu shot had a lower risk of getting COVID-19. That’s particularly important for that age group as they are the ones most likely to experience life-threatening complications from COVID-19.

But what could explain getting a two-fer from one vaccine? Well, there’s a growing body of research that points to something called “trained innate immunity”. Our bodies have two different kinds of immune system, adaptive and innate. Vaccines activate the adaptive system, causing it to develop antibodies to attack and kill a virus. But there’s also evidence these same vaccines could trigger our innate immune system to help fight off infections. So, a flu vaccine could boost your adaptive immunity against the flu, but also kick in the innate immunity against the coronavirus.

In an article in Scientific American, Ellen Foxman, an immunobiologist and clinical pathologist at the Yale School of Medicine, says that might be the case here: “There is evidence from the literature that trained immunity does exist and can offer broad protection, in unexpected ways, against other pathogens besides what the vaccine was designed against.”

The researchers in the Netherlands wanted to see if there was any evidence that what they saw in their hospital had any basis in fact. So, they devised a simple experiment. They took blood cells from healthy individuals and exposed some of the cells to the flu vaccine. After six days they exposed all the cells to the SARS-CoV-2, the virus that causes COVID-19.

Compared to the untreated cells, the cells that had been exposed to the flu vaccine produced more virus-fighting immune molecules called cytokines. These can attack the virus and help protect people early on, resulting in a milder, less dangerous infection.

All in all it’s encouraging evidence that a flu shot might help protect you against the coronavirus. And at the very least it will reduce your risk of the flu, and if there’s one thing you definitely don’t want this year it’s having to battle two life-threatening viruses at the same time.

Want to help us solve a mystery?

Patient that has recovered from Covid-19 donating blood plasma. Photo courtesy Science Photo

Convalescent plasma has been in the news a lot lately as a potential treatment for people infected with the coronavirus. In August the US Food and Drug Administration (FDA) granted emergency use authorization (EUA) to use these products based on preliminary data that suggested it might help people battling COVID. But there are still a lot of unanswered questions about this approach.

And that’s where you come in.

Plasma is a component of blood that carries proteins called antibodies that are usually involved in defending our bodies against viral infections.  We also know that blood plasma from patients that have recovered from COVID-19, referred to as convalescent plasma, contain antibodies against the virus that can be used as a potential treatment for COVID-19. 

That’s the theory, but the reality is that there are still a lot we don’t know, basic questions such as does it really work, how does it work, does it work for everyone or just some patients? A clinical  grant includes testing the plasma in COVID-19 Positive patients that CIRM is funding with City of Hope, UC Irvine and Translational Genomics Research Institute (TGen) hopes to answer those questions. 

The first step is getting the plasma from people who have recovered from COVID and then testing it to make sure it’s safe and to identify what blood type it is, so you can match that blood type with the person receiving it.

But plasma doesn’t contain just one kind of antibody, there are many antibodies and each one works in a slightly different way. For example, two antibodies, IGM and IGG, target in on the spike protein on the coronavirus. The goal is to block that spike and prevent the virus from spreading throughout the body. IGM has up to 10 ‘arms’ and so has the potential to bind multiple copies of the spike, whereas IGG has only 2 arms, but lasts longer. Both IGM and IGG also come in many different flavors, allowing them to bind to many different parts of the spike, some being more protective than others.

That’s one of the things that this trial is trying to find out. And you can help them do that. The trial needs volunteers, volunteers to donate the plasma and volunteers to try the therapy.

The team is evaluating changes that occur before and after plasma treatment.  Many recipients have no immediate response, a few get dramatically better, and some continue to have symptoms long after discharge from the hospital.  These so-called “long-haulers” can have debilitating problems, months after becoming infected. The study hopes to evaluate these variable responses to plasma treatment.

But more people are needed if we are to truly understand what works best. We need people who are newly infected, those being treated with plasma, and those that have recovered from the virus.

We are particularly interested in recruiting people from the Black and Latinx communities, groups that are often underserved when it comes to access to medical care.

The team has created a website to make it easy to find out more about the clinical trial, and to see if you are a good candidate to be part of it, either as a donor or recipient.

Lives are at stake and time is short so join us, help us find answers to the most pressing medical issue of our times. It’s a chance to do something that might benefit your family, your friends and your community.