Jean Camden

Four months in, Baker lab hits the ground running and won’t be stopping anytime soon

October 19, 2020 By Lauren Hines in Research Tags: cancer, cell sheets, copper

Post doctorate Harim Tavares from the Baker lab works in “the hood,” which is a space used to prevent researchers and other outside factors from contaminating cells.

By Lauren Hines | Bond LSC

Saliva is often something people take for granted.

It helps break down food, maintain teeth and keep the oral cavity feeling comfortable. But head and neck cancer patients lose those benefits when chemotherapy treatments damage their salivary glands.

Olga Baker set out to research tissue regeneration for these cancer patients by collaborating with the Michael Petris and Gary Weisman labs after setting up shop four months ago as a new principal investigator at Bond Life Sciences Center.

Together, the Petris and Baker labs are looking at the role of copper in salivary gland damage.

“Nobody has asked what happens to copper metabolism during and after head and neck radiation,” Baker said. “Is copper related to the fibrosis that is developing in those patients, so they don’t make saliva? We don’t know. So, we are answering different questions…. We don’t have any data yet, but what we have is immunofluorescence studies showing that those copper transporters are present in salivary glands from mice and humans.”

If the two labs can learn how copper connects to salivary gland tissue regeneration, Baker can get a step closer to helping patients.

The Baker and Petris labs just published a paper with help from the Proteomics Center and the MU Molecular Interactions Core in the journal of Dental Research. Post doctorate Harim Tavares from the Baker lab is the leading author.

The study used synthetic networks of crosslinked polymer chains that can take in large amounts of water called, smart hydrogels. The smart hydrogels were used in the same mouse model as the cell sheets and promoted tissue regeneration on mouse salivary glands. The paper explored how different materials like smart hydrogels can improve tissue regeneration.

Baker’s other focus takes on cancer and tissue regeneration from a different angle in her collaboration with the Weisman lab.

“Dr. Weisman’s group has studied the mechanisms of salivary gland dysfunction for over 30 years, so between these two groups the tools are in place to provide a translational approach to understand and treat salivary gland disorders,” said Jean Camden, a senior research associate in the Weisman lab.

The two labs just submitted a paper on mouse submandibular glands and cell sheets, which are plastic-like sheets where cells grow and detach once it reaches a certain temperature. Kihoon Nam from the Baker lab is the corresponding author. The study transplanted submandibular gland cell sheets into a wounded mouse to see if cells could be transferred.

“We believe that is a good proof of concept for future use in radiation studies,” Baker said.

The Baker lab uses cell sheets with the Weisman lab to study the role of the P2Y2 receptor in salivary gland regeneration. P2Y2 is a plasma membrane receptor that binds the molecules outside of cells and serves as signals to trigger an action.

The Weisman lab previously showed that P2Y2 receptor activation encourages salivary gland cells to migrate together and form a unit capable of secreting saliva.

“At this time, we don’t know what the role of P2Y2R is in the cell sheets,” Camden said. “That is an aim we proposed in a recent TRIUMPH proposal.”

The TRIUMPH initiative — The Translational Research Informing Useful and Meaningful Precision Health initiative — is a pilot grant funding opportunity through the Missouri School of Medicine.

As if two collaborations weren’t enough, Baker is also working on saliva substitutes. The lab just submitted a grant to fund the project.

“If we get the money, we will be able to make a far better saliva substitute as compared to the Biotine, or Aquoral, or Oasis,” Baker said. “Those are the three leading brands. So, hopefully, we can make something better here at MU and commercialize the product.”

Beyond the Vaccine

September 25, 2020 By Lauren Hines in Research Tags: COVID-19, virology

Lucas Woods from the Weisman lab watches lung cancer cells and oral epithelial cells grow. | photo by Lauren Hines, Bond LSC

By Lauren Hines | Bond LSC

Vaccine development remains a central goal to get the current COVID-19 pandemic under control. While vaccines are highly vital in the fight against the current pandemic, what if scientists could prevent the virus from entering cells altogether? Researchers at Bond Life Sciences Center are working to do just that and, so far, they’re the only ones at Mizzou on the case.

For the Gary Weisman lab, that starts with their study of a family of purinergic receptors which are found on the plasma membrane of cells. Molecules outside the cell bind to receptors and serve as signals to trigger an action, whether it’s transporting something into a cell, alerting its defenses or initiating programmed cell death. The specific receptors they study sound off one of the first alarms to alert host immune cells when a cell is damaged.

Weisman, Bond LSC principal investigator and Curators’ Distinguished Professor of biochemistry, noticed that the spike protein in the virus that causes COVID-19, SARS-CoV-2, shares an amino acid sequence — arginylglycylaspartic acid or RGD — with one of the receptors his lab studies named, P2Y2.

“So, we had this one niche that no one I think has followed,” Weisman said. “Even though people understand RGD sequences are important for protein to protein interactions, and possibly viral entry, no one has looked at this with respect to coronaviruses.”

While ACE2, a plasma membrane receptor, serves as the primary cell-surface receptor for SARS-CoV-2 binding, a potential role for the RGD sequence in the spike protein is to bind to alternate receptors and subsequently enhance viral infectivity.

“We postulated that if there was a way to use our receptor, it might be to block the entry of the virus,” Weisman said. “The virus can’t replicate on its own. It has to get inside the cell to be replicated, so if we prevent the entry, we can potentially stop the infections.”

They found plasma membrane receptors like ACE2 and P2Y2 all share this sequence that binds to other cell-surface receptors called, integrins. The lab is currently exploring ways to block these pathways without blocking other functions.

Few other labs have made this connection because RGD is not known to be present on many of the membrane receptors. In addition, the Weisman lab already has the supplies and connections to study these receptors.

“We, as the lab, have been studying this receptor and this family of receptors for so long that if there is a lab that has the tools and the knowledge to answer this question, I definitely think that is us,” said Kevin Muñoz Forti, Ph.D. candidate for the department of biochemistry.

Kevin Muñoz Forti is doing cell culture work in “the hood,” which is a space used to prevent researchers and other outside factors from contaminating the cells. | photo by Lauren Hines, Bond LSC

The lab partners with Kamal Singh, assistant director of the Molecular Interactions Core at Mizzou and associate research professor in the department of veterinary pathobiology, who works with viruses in a way that won’t infect workers.

Singh achieves this by using look-alikes, or pseudovrises, of the spike protein on SARS-CoV-2. To the cell, this mimics the outer shell of SARS-CoV-2, but is not contagious.

Even though the Centers for Disease Control and Prevention and Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, expect a vaccine soon, this work is for the long run.

“I can guarantee you this isn’t the last coronavirus that will come up,” Singh said. “There will be many because it has been kind of periodic lately. Coronaviruses have been emerging, so the research done in collaboration with Gary’s lab will definitely be available for… future coronaviruses.”

Coronaviruses are a family of viruses which may cause respiratory illness in humans. The most recent diseases, before COVID-19, caused by previous coronaviruses were Severe Acute Respiratory Syndrome (SARS) from 2002 and Middle East Respiratory Syndrome (MERS) from 2012. Severe Acute Respiratory Syndrome Coronavirus 2 is the virus that causes COVID-19.

“This is the virus that causes COVID-19 or SARS-CoV2,” said Lucas Woods, Weisman research lab manager. “If this type of research were to have been investigated during the first coronavirus epidemic, there might have been some type of lead on the type of work we’re doing… so, absolutely this work will be useful after a vaccine or treatment is available.”

Looking ahead, the study has two years of funding from the American Lung Association in addition to grants from the National Institutes of Health. The Weisman lab hopes to eventually make it to clinical trials, but the road from basic research to clinical trials is long and arduous.

“What’s on our side, at least for the future, is that with some of these pathways we’re looking at, there are already available drugs that target these particular pathways,” Woods said.

These pathway-blocking drugs aren’t approved for humans yet, but this research could facilitate clinical scientists to test the safety of these or related drugs in humans.

The Weisman lab’s research of P2 receptors can be applied to many systems in the body and other diseases. This also allows for more ways to receive grants to fund studies longer. Along with the COVID-19 studies, they study P2 receptors in diseases that affect salivary glands.

Cheikh Seye, Mizzou professor of biochemistry, studies vascular diseases that relate to the receptors studied by the Weisman lab. Seye understands that one of the complications of COVID-19 in humans is vascular related.

“I mean there’s a lot of interaction between the vasculature and other systems, so it doesn’t stay with the salivary gland,” Seye said. “It’s all interconnected, so that’s why we need to have a multi-dimensional approach.”

In addition, the lab has found commonalities between oral and lung epithelial tissue that may contribute to COVID-19.

While this study has quite a bit of potential, it’s a long way away from seeing practical results.

“All the people in the lab have confidence because they have been successful on their own doing this before,” Weisman said. “So, it’s just another challenge, but we know how to get the answers, we have the tools and we’re optimistic that we’ll find out something.”

Researchers working on this study include Gary Weisman, Kamal Singh, Lucas Woods, Cheikh Seye, Jean Camden and Kevin Muñoz Forti.

The Lab in Time of COVID-19

April 29, 2020 By Lauren Hines in Research Tags: COVID-19, Marc Johnson

The main halls of Bond LSC are empty due to researchers being told to work from home. | photo by Roger Meissen, Bond LSC.

By Lauren Hines | Bond LSC

On an average day, you can find post doctorate Norman Best surrounded by corn in the greenhouse or at his bench in the McSteen lab doing molecular work. However, since Columbia and state leaders issued a stay-at-home order on March 25 to prevent the spread of COVID-19, this means Bond LSC is mostly empty and researchers like Best are at home writing.

“It’s definitely made me appreciate what I had before,” Best said.

Coronaviruses are a family of viruses that can cause respiratory illness in humans. They’re found circulating among animals, and then passed to humans. While the world has seen dangerous coronavirus outbreaks including severe acute respiratory syndrome (SARS) in 2003 and Middle East respiratory syndrome coronavirus (MERS) in 2012, the 2019 emergence of COVID-19 has spread much more quickly.

According to the Centers for Disease Control and Prevention, COVID-19 is spread through respiratory droplets produced when an infected person coughs, sneezes or talks. Staying at home and avoiding contact with others will help prevent the spread.

Most researchers are working from a distance, like Best who is writing a paper on how the plant hormones auxin and brassinosteroid affect lateral meristem growth. However, some are deemed essential whether it’s to water plants, finish crucial experiments or study COVID-19 itself.

Marc Johnson, professor of molecular microbiology and immunology, is currently studying glycoproteins which are proteins on the surface of viruses that dictate what cell they’re going to infect. Even though Johnson usually works on HIV, he’s shifting his focus to COVID-19 and its glycoproteins called, spike.

Johnson is taking other viruses and replacing their glycoproteins with COVID-19 spike proteins to basically create a safe version of our current coronavirus. This will allow him to do multiple tests to try to inhibit viral entry.

In addition, these experiments can also test the effectiveness of antibodies. Recovered patients are donating their plasma — blood without red blood cells and just antibodies — to transfer their coronavirus-fighting antibodies to other patients.

Marc Johnson observes cells modified with CRISPR under the microscope. | photo by Jennifer Lu, Bond LSC.

“Of course, if you take plasma from a patient, you want to make sure that there are the antibodies you want in there, so that’s where my [experiment] would come into play to check whether there’s a high level of neutralizing antibodies in their serum,” Johnson said. “If there is, then you know it’s good for injecting. It might be helpful for the patient.”

For those who aren’t working on COVID-19, the interruption has some feeling frustrated.

When Best was in the lab, he was doing molecular work on creating a CRISPR construct. CRISPR is a method of editing genes, essentially splicing DNA into a cell. Now, it’s sitting in the freezer half done.

“I’m working on finishing up a few publications that I’ve had data for that I’ve actually

not been able to analyze before,” Best said. “I had not taken the time to analyze as much as I have now because I am sitting all day on the computer…However, there are still a few things left to do in the lab that have been delayed because of quarantining.”

Jean Camden, senior research associate in the Weisman lab, goes into Bond LSC once a week to check on the mouse breeding colony in addition to working from home.

“For us, the timing was good,” Camden said. “We had just finished some large experiments, and we are now writing, all of us. We have plenty of work to do at home.”

For many researchers, as Camden describes, writing papers is one of the last tasks to do.

“Now there’s no excuse,” Camden said. There’s nothing else to do but write.”

However, even the mounds of data researchers have been sitting on will eventually run out.

“If [the end of social distancing] doesn’t happen within the next two or three weeks, then we will be getting behind on getting experiments done,” Camden said.

So far, MU has moved in-person summer classes online, but is hopeful to re-open campus in the fall under a “new normal.”

“[The end of social distancing] should depend on our preparedness and the resources because one of the reasons why I think we shut down is that we weren’t ready to cater for all the people that were going to be sick, and so the best option was to prevent it,” said Kwaku Tawiah, fifth year graduate student who studies Ebola in the Donald Burke lab. “I don’t know when normal life can return as we knew it before.”

Even though there’s a lot of uncertainty of what’s ahead, Bond LSC researchers are learning to adapt and are continuing their research.

“It is very fortunate that I have been able to work at home and keep my job,” Camden said. “A lot of people here in Columbia have been laid off, and I feel bad for the terrible things that have happened. So, I appreciate the position that I’m in.”

At the moment, Best is still sitting at home with his dog analyzing data and writing. He expects his paper on lateral suppressor1 to be published soon among many others in the works.

“I think we’re all ready to get back to normal life,” Camden said.