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Tag: Kulp

Wistar Scientists Successfully Engineer a Goldilocks Construct: Therapeutic Antibody Could Be a Future Medicine to Improve Outcomes for Melanoma

Written by The Wistar Institute on . Posted in Featured News.

In recent years, multimodal therapies have emerged as a route to treat cancer by delivering different types of treatments together to improve effectiveness. However, the more modalities there are, the more complex the production and effects of these lifesaving treatments can become.

Wistar researchers have engineered a linked molecule that enables a three-modality therapy for treating melanoma. They accomplished this by connecting a cytokine and an antibody—which would ordinarily be administered separately—and then engineering a form that was pro-inflammatory enough to fight the cancer cells but not so inflammatory as to cause complications or reduce survival outcomes, according to a recently published study in Frontiers in Immunology.

“We took aspects of a cancer treatment regimen and tried to simplify that by combining antibody and cytokine together,” said Nicholas Tursi, the lead author on the study and a graduate student researcher in the lab of Dr. David Weiner, executive vice president, director of the Vaccine & Immunotherapy Center, and W.W. Smith Charitable Trust Distinguished Professor at The Wistar Institute. “I focused on engineering an intermediate cytokine that is efficacious but also has an acceptable pro-inflammatory profile—a Goldilocks approach.”

The engineered “Goldilocks” cytokine Tursi and his colleagues, including Dr. Weiner and Dr. Daniel Kulp, Associate professor in Wistar’s Vaccine & Immunotherapy Center, engineered to test their antibody cytokine chimera was called HL2-KOA1, a modified designer version of the T cell growth factor IL-2. This engineered molecule used in a combination therapeutic regimen was effective at promoting survival in a rigorous melanoma model.

“What this suggests is that we could use other antibodies or cytokines to engineer the immune response to further extend efficacy,” said Tursi. He is hopeful that this research will serve as the foundation for developing other antibody cytokine chimeras that work for melanoma and potentially other cancers.

A Wistar Journey Through the Past, Present, and Future of Immunization Work

Written by The Wistar Institute on . Posted in Featured News.

Vaccines are a crucial public health tool in its’ arsenal against diseases. Resurgences of diseases long thought eradicated are popping up decades later in sewage waters here and abroad, and we’ve witnessed what the impact of war has on countries whose health systems have crumbled under the ravages of war—we are not as far removed as we’d like to be from diseases once prevented by vaccines. With more than half a century of basic research for vaccine development, The Wistar Institute plays an integral role in immunization around the globe.

Rubella, rabies, and rotavirus. Wistar scientists developed vaccines for these diseases that are used in immunization programs worldwide. The rubella vaccine by Wistar scientists effectively ended the pandemic in the United States, as declared by the CDC in 2005. Two rabies vaccinations developed from the Institute addresses the disease in both animals and humans. In 2006, Wistar and collaborators created a rotavirus vaccine which became part of the regular immunization schedule for U.S. babies and is used or approved in over 45 countries. And we’re just getting started.

“Immunization is possibly one of the most impactful medical interventions ever developed. Millions of lives are saved each year by vaccination, and we live healthier and longer lives due to vaccines.” states David Weiner, Ph.D., Executive Vice President, Director of Wistar’s Vaccine & Immunotherapy Center, and W.W. Smith Charitable Trust Professor in Cancer Research, in the Immunology, Microenvironment & Metastasis Program at Wistar’s Ellen and Ronald Caplan Cancer Center.

This National Immunization Awareness Month, we have shared a few snapshots of current vaccine development projects at the Institute as well as what these researchers’ hopes are for the future of immunization.

Tackling Both Infectious Disease and Cancer with Immunization

Dr. Weiner’s research takes on both infectious disease and cancer. His work encompasses developing new ways to build and deliver synthetic nucleic acid vaccines – particularly advancing a new approach that drives self-assembly of an antigen into a more potent vaccine inside a vaccinated person. This approach gives the body the genetic information to become the factory to create the vaccine. Furthermore, his lab is developing new types of cancer therapeutic vaccines with the goals of creating strong anti-cancer immunity and eradicating cancer cells.

Weiner’s collaborations with public and private institutions is centered around novel immunization technology developed from his lab called DNA-encoded monoclonal antibodies (DMAbs) against diseases such as COVID-19, Zika, and Ebola.

Regarding the future, he shares, “Together with our collaborators, we hope to move new prototype HIV vaccines into human clinical trials later this year, and continue to advance vaccines for emerging pathogens, as well as cancer immunotherapies.”

Developing DNA Vaccines

Ami Patel, Ph.D., Caspar Wistar Fellow in the Vaccine and Immunotherapy Center, focuses her scientific efforts on DNA vaccines which have potential to be more stable and economical over traditional vaccine production. “We are trying to understand how different vaccines work in the body. How do vaccines generate different types of immune responses and can we use this to understand protection against infectious diseases. We are using this information to help develop the next generation of potential vaccines.” she says.

Patel emphasizes the importance of vaccines for young children and adults by calling back to various infectious diseases like polio that are no longer very common because of immunization. “Vaccines help protect us against serious disease. Some of us remember the discomfort of chicken pox as children. There is now a vaccine.”

While she calls the COVID-19 pandemic “devastating to global health”, Patel also recognizes the pandemic’s challenges proved fertile ground for an extraordinary collaborative time for biomedical scientists. “My hope is for vaccine researchers across different disciplines to continue to work together to help us understand different infectious diseases and develop better vaccines.”

Zooming in on a Nanoscale

In collaboration with Weiner, Daniel Kulp, Ph.D., associate professor in the Vaccine and Immunotherapy Center, has embraced nanotechnology in his vaccine research. “We are developing rationally engineered nanoparticle vaccines that can elicit extremely broad coronavirus immunity providing a proof-of-concept that a pan-coronavirus vaccine is possible,” Kulp elaborates.

While the Kulp laboratory is developing several promising vaccines, he emphasizes that his goal is to assess these candidates in humans. He says, “We are working to reduce barriers for launching small experimental medicine clinical trials allowing for broader evaluation of our best vaccine concepts. Through this type of work, I have high hopes that our generation can claim credit for the eradication of SARS-CoV-2.”

Kulp expresses that “Vaccines are one of the single most effective medical technologies humans have developed saving hundreds of millions of lives. Vaccines do not work without immunizations. This message is incredibly important.”

Highlighting Vaccine Research at The Wistar Institute Through the Penn-CHOP-Wistar Vaccine Symposium

Written by The Wistar Institute on . Posted in Featured News.

From HIV to COVID-19, Wistar scientists are at the forefront of vaccine development. Read our recap of the recent Vaccine Symposium and the impactful research in progress at the Institute.

This past Monday, The Wistar Institute, University of Pennsylvania Perelman School of Medicine, and Children’s Hospital of Philadelphia held the Penn-CHOP-Wistar Vaccine Symposium. Hosted both in-person at the Smilow Center for Translational Research and online, the all-day event covered the history of vaccines and current vaccine research from the three sponsoring institutions.

Keynote speaker and Wistar professor emeritus Stanley Plotkin, M.D., is a prominent researcher who is known for the development of the rubella vaccine while he was a virologist at The Wistar Institute. Furthermore, his years of work helping in vaccine efforts for rabies, rotavirus, and cytomegalovirus have stimulated much innovation in the biomedical research community.
After giving a brief history of vaccines, Plotkin proclaimed “Vaccinology has taken off. … We are now in a golden age of vaccinology.”

The Symposium’s research presentations opened with Wistar’s Daniel Kulp, Ph.D., Associate Professor in the Vaccine & Immunotherapy Center, and his work on a novel COVID-19 nanoparticle vaccine. Amelia Escolano, Ph.D., Assistant Professor in the Vaccine & Immunotherapy Center, also spoke about her efforts investigating immunization strategies for HIV. Wistar’s Vaccine & Immunotherapy Center Director David B. Weiner, Ph.D., gave a summary of his research into the genetic delivery of vaccines, calling the innovation of vaccinology in Pennsylvania among these institutions “extraordinary”.

The current global pandemic has reinforced the need for scientific solutions and a deeper understanding of human diseases. It is the studies and ideas from research centers like The Wistar Institute and its colleagues that propel forward biomedicine. As keynote speaker Plotkin stated, “Pandemics have occurred throughout the history of humankind and will continue to do so in the future. Infectious diseases of humans will continue to happen. Therefore, we must act against them.”

Dr. Daniel Kulp works with a fellow scientist in a Wistar lab

Wistar Study Opens the Door to Faster, Cheaper HIV Vaccine Research

Written by The Wistar Institute on . Posted in Featured News.

For the first time, scientists have developed an DNA-encoded immunogen that produces Tier-2 antibodies—the kind that matter for combatting HIV

Nearly four decades after its discovery, HIV has killed 36.3 million people, with no vaccine in sight. Part of the reason vaccine development has been slow is because trialing candidate vaccines that produce Tier-2 neutralizing antibodies—the kind that matter for combatting HIV—has always required long and expensive experiments in large animal models like rabbits and macaque monkeys.

An effective HIV vaccine needs to produce antibodies that protect against the most common variants of HIV, which are categorized as “Tier 2” viruses based on how quickly and easily they can be neutralized by antibodies (more quickly/easily than Tier 3, less than Tier 1).

A new study by scientists at The Wistar Institute shows a quicker, less expensive path to developing this tier of antibodies. For the first time, these scientists have demonstrated a method for eliciting Tier-2 neutralizing antibodies in mice.

“Mice are the workhorse of vaccine design and development because you can iterate lots of concepts in that model due to cost and time constraints,” said Daniel Kulp, Ph.D., associate professor in the Vaccine & Immunotherapy Center at The Wistar Institute.

The scientists developed an immunogen—a substance that causes an immune response—called a native-like trimer, which they administered to mice. Importantly, they encoded the immunogen in DNA, which turns the host bodies (in this case the mice) into “antigen factories” instead of requiring what would otherwise be a complex and expensive vaccine manufacturing process.

They then compared the results from the mice who received the DNA-encoded native-like trimer to results from mice who received a standard protein immunization. Only those mice that received the DNA-encoded native-like trimer developed Tier-2 neutralizing antibodies.

From there, they were able to isolate and examine the atomic structure of one of the antibodies that their immunogen had produced. “The structure gives us incredible insight into how this antibody is able to neutralize the virus,” said Kulp.

“Our data demonstrates the value of this approach as a tool to create surgically tailored immunity against a difficult pathogen’s vulnerable sites, in this case for HIV,” said coauthor David B. Weiner, Ph.D., executive vice president and director of the Vaccine & Immunotherapy Center and the W.W. Smith Charitable Trust Professor in Cancer Research at The Wistar Institute.

HIV cells

Wistar Scientists Move HIV Vaccine Research Forward by Developing an Immunogen that Produces Tier-2 Antibodies—the Kind That Matter for Combatting HIV

Written by The Wistar Institute on . Posted in Press Releases.

PHILADELPHIA — (Feb. 4, 2022) — Nearly four decades after its discovery, HIV has killed 36.3 million people, with no vaccine in sight. However, a new study by researchers at The Wistar Institute, an international biomedical research leader in cancer, immunology, infectious disease, and vaccine development, takes a promising step in the direction of developing an HIV vaccine.

The findings, published in Nature Communications, demonstrate the promise of using a unique native-like trimer to develop Tier-2 neutralizing antibodies—the kind that matter for combatting HIV—in mice for the first time.

Previously, eliciting these types of antibodies using candidate vaccines required long and expensive experiments in large animal models creating a significant bottleneck on HIV-1 vaccine development. “With our new finding, we have opened the door to rapid, iterative vaccinology in a model that can produce Tier-2 neutralizing antibodies, enabling development of more advanced HIV vaccine concepts,” said Daniel Kulp, Ph.D., associate professor in the Vaccine & Immunotherapy Center at The Wistar Institute and corresponding author on the paper.

The researchers encoded the native-like trimer into DNA for delivery into the mice. This has the practical advantage of turning the host bodies into “antigen factories” instead of requiring what would otherwise be a complex vaccine manufacturing process. The researchers then compared the results from the mice who received the DNA-encoded native-like trimer to results from mice who received a standard protein immunization. Only those mice that received the DNA-encoded native-like trimer developed Tier-2 neutralizing antibodies.

“We were able to generate strong immune responses with both platforms, but the DNA platform uniquely drove this neutralizing response,” said Kulp.

Once they’d verified their immunization regime was producing Tier-2 antibodies, Kulp and his colleagues isolated monoclonal antibodies from the mice and used cryo-electron microscopy to determine the atomic structure of one Tier-2 neutralizing monoclonal antibody. They found that the antibody binds to an epitope (a segment of a protein that sticks out of the antigen, which prompts an immune response) called C3V5. In the gold standard HIV vaccine model (non-human primates), prior research has shown that antibodies binding to C3V5 protect animals from a SHIV infection, which is a close relative of HIV that infects non-human primates.

“The structure gives us incredible insight into how this antibody is able to neutralize the virus,” said Kulp. “For the first time, we can strategize about how to design new vaccines that can generate broadly neutralizing antibody responses to the C3V5 epitope.”

Coauthor David B. Weiner, Ph.D., executive vice president and director of the Vaccine & Immunotherapy Center and the W.W. Smith Charitable Trust Professor in Cancer Research at The Wistar Institute, emphasized the utility of their findings.

“What we’ve done is enable direct in vivo self-assembly of structurally designed immunogens, which are engineered and delivered using nucleic acid technology, inside the vaccinated animal. Our data demonstrating induction of autologous Tier 2 neutralization illustrate the value of this approach as a tool to create surgically tailored immunity against a difficult pathogen’s vulnerable sites, in this case for HIV.”

Co-authors: Ziyang Xu, Susanne Walker, Neethu Chokkalingam, Mansi Purwar, Edgar Tello-Ruiz, Yuanhan Wu, Sonali Majumdar, Kylie M. Konrath, Abhijeet Kulkarni, Nicholas J. Tursi, Faraz I. Zaidi, Emma L. Reuschel, Ishaan Patel, April Obeirne, David B. Weiner, and Daniel W. Kulp from The Wistar Institute; Megan C. Wise, Katherine Schultheis, Lauren Gites, Trevor Smith, Janess Mendoza, Kate E. Broderick, and Laurent Humeau from Inovio Pharmaceuticals; Alan Moore, Jianqiu Du, and Jesper Pallesen from Indiana University.

Work supported by: National Health Institutes (NIH) IPCAVD Grant U19 Al109646-04; W. W. Smith Charitable Trust; and Wistar Monica H.M. Shander Memorial Fellowship.

Publication information: Induction of Tier-2 Neutralizing Antibodies in Mice with a DNA-encoded HIV Envelope Native Like Trimer, Nature Communications, 2022. Online publication.

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The Wistar Institute is an international leader in biomedical research with special expertise in cancer research and vaccine development. Founded in 1892 as the first independent nonprofit biomedical research institute in the United States, Wistar has held the prestigious Cancer Center designation from the National Cancer Institute since 1972. The Institute works actively to ensure that research advances move from the laboratory to the clinic as quickly as possible. wistar.org.

A coronavirus cell

Wistar Scientists Behind the Next Wave of COVID-19 Vaccines

Written by The Wistar Institute on . Posted in Featured News.

Current COVID-19 vaccines were created in record time, but scientists are working to make better, longer lasting vaccines that could be used around the world.

The first generation of COVID-19 vaccines have been highly effective, but also have limitations: their efficacy can wane without a booster shot, and they may be less effective against some variants. Now scientists at The Wistar Institute have developed a more targeted vaccine that, in animal studies, shows stronger, broader, and more durable protection in a single, lower dose.

“This is among the first second-generation vaccines that will have more advanced features and broader protection,” said Daniel Kulp, Ph.D., associate professor in the Vaccine & Immunotherapy Center and corresponding author of the study.

The vaccine combines three technologies — immune focusing, self-assembling nanoparticles, and DNA delivery — into a single platform for the first time.

Immune focusing means that researchers engineered an immunogen that targets specific areas of COVID’s famous “spike” protein to generate protective antibodies. Instead of replicating the whole structure, this immunogen blocks specific sites that produce non-neutralizing antibodies. This stimulates higher production of neutralizing antibodies — the kind of antibodies that help the immune system fight the virus.

Having higher levels of these important antibodies can reduce the chance that the vaccine’s effectiveness will wane over time.

Studies in mice found that 100% of animals who received a single dose of the new vaccine were protected from death after virus challenge, whereas only 20% of animals receiving the first-generation vaccine were protected.

Nanovaccines consist of extremely small (nano) particles—similar in size to bacteria and viruses—used to display multiple copies of an antigen and able to elicit strong immune responses. The new vaccine also uses DNA to instruct cells to make these vaccines. Kulp noted that DNA vaccines can be stored at room temperature, making it potentially easier to transport to remote or developing locations than existing approved vaccines (such as mRNA vaccines), which require specialized cold storage. DNA vaccines historically also have an excellent safety profile, with a very low chance of eliciting severe adverse effects amongst clinical trial participants.

“Current vaccine effects on reducing transmission of SARS-CoV-2 variants of concern including Delta and Omicron could be improved for their breadth of protection as well as their immune potency,” said co-author David B. Weiner, Ph.D., executive vice president, director of the Vaccine & Immunotherapy Center and the W.W. Smith Charitable Trust Professor in Cancer Research, at The Wistar Institute.

The scientists are seeking funding and partnership to begin human trials of the new vaccine.

Dr. Kulp’s research was made possible through the generous support of Wistar donors who contributed to this project through the Wistar Coronavirus Discovery Fund.

Dr. Daniel Kulp writes on a whiteboard

Novel Nanoparticle SARS-CoV-2 Vaccine Combines Immune Focusing and Self-assembling Nanoparticles to Elicit More Potent Protection

Written by The Wistar Institute on . Posted in Press Releases.

PHILADELPHIA — (Feb. 1, 2022) — The first generation of COVID-19 vaccines have been highly effective, but also have limitations: their efficacy can wane without a booster shot, and they may be less effective against some variants. Now scientists at The Wistar Institute have developed a more targeted vaccine that, in animal studies, shows stronger, broader, and more durable protection in a single, low dose.

The vaccine combines three technologies – immune focusing, self-assembling nanoparticles, and DNA delivery – into a single platform for the first time. In addition to its other advantages, the vaccine could be stored at room temperature, making it potentially easier to transport to remote or developing locations than existing mRNA vaccines, which require specialized cold storage.

“This is among the first next-generation vaccines that will have more advanced features and broader protection,” said Daniel Kulp, Ph.D., associate professor in the Vaccine & Immunotherapy Center at The Wistar Institute and corresponding author of the study.

The paper, “Nucleic acid delivery of immune-focused SARS-CoV-2 nanoparticles drive rapid and potent immunogenicity capable of single-dose protection,” was published in the journal Cell Reports.

Existing vaccines include an unmodifided receptor binding domain of SARS-CoV-2 spike protein. The new vaccine includes a rationally engineered receptor binding domain using computational and structure-based design methodologies. The engineered receptor binding domain blocks ‘immune distracting’ sites and can therefore elicit stronger levels of protective, neutralizing antibodies.

Researchers then used naturally self-assembling proteins to form nanoparticles which display these highly engineered immunogens. By arranging themselves into structures that resemble an actual virus, the nanoparticles are more easily recognized by the immune system and transported to the germinal centers, where they activate B cells which produce protective antibodies.

Using nucleic acid vaccine delivery technology similar to mRNA, the nanoparticle vaccine is encoded in DNA and delivered into cells thereby giving genetic instructions for the body to build the immunogen internally. This is an advance over traditional vaccines that must be manufactured in specialized factories through complex vaccine production processes. In contrast to other vaccines, Dr. Kulp noted that one advantage of the DNA platform is that it doesn’t require refrigeration and it can also be quickly reformulated to target new variants.

In animal models, researchers found that the DNA delivered immune-focused nanoparticle vaccine produced much higher levels of neutralizing antibodies than the vaccine that wasn’t immune-focused.

“A difficulty with current vaccines is that neutralizing antibodies decline over time,” Kulp said. The nanoparticle vaccine produced durable responses after a single immunization out to six months in mice, unlike what we are seeing with current SARS-CoV-2 vaccines in people.

The ultimate test for SARS-CoV-2 vaccine candidates is protection from death in SARS-CoV-2 challenge experiments. The researchers found that in a lethal challenge model 100% of mice who received the immune-focused nanoparticle vaccine were protected from death with a single low dose. Most mice who received the standard, non-immune focused vaccine died within 10 days of challenge.

The vaccine assessment was conducted in both wild-type mice and mice that were genetically engineered to mimic human immune systems, he noted.

Even without being updated, the immune-focused vaccine showed a comparable level of antibody production to Delta, and other variants, Kulp said. That’s partly because of the immune focusing approach itself, he noted; in blocking parts of the receptive binding domain for the purpose of inhibiting non-neutralizing antibodies, it also blocks many of the areas affected by spike protein mutations. Studies on the Omicron variant are underway.

Researchers are seeking funding to begin human trials of the vaccine.

Co-author David B. Weiner, Ph.D., executive vice president, director of the Vaccine & Immunotherapy Center and the W.W. Smith Charitable Trust Professor in Cancer Research, at The Wistar Institute, said the vaccine could provide a needed step forward to improve protection against COVID-19.

“Current vaccine effects on reducing transmission of SARS-CoV-2 variants of concern including Delta and Omicron could be improved for their breadth of protection as well as their immune potency,” Weiner said. “This study demonstrates that using a nucleic acid approach combined with in vivo structural assembly of a glycan immune-focused nanoparticle drives single protection and neutralization against diverse variants of concern in a dose-sparing formulation. Additional studies of this vaccine approach for SARS-CoV-2 appear timely and important.”

Co-authors: Kylie M. Konrath, Kevin Liaw, Yuanhan Wu, Xizhou Zhu, Susanne N. Walker, Ziyang Xu, Neethu Chokkalingam, Nicholas J. Tursi, Mansi Purwar, Emma Reuschel, Drew Frase, Benjamin Fry, and Ami Patel from Wistar; Katherine Schultheis, Igor Maricic, Viviane M. Andrade, Kate E. Broderick, Laurent M.P.F. Humeau, and Trevor R.F. Smith from Inovio Pharmaceuticals; Himanshi Chawla and Max Crispin from the University of Southhampton; Jianqiu Du and Alan Moore from Indiana University; Jared Adolf-Bryfogle and Jesper Pallesen from the Institute for Protein Innovation; Matthew Sullivan from the University of Pennsylvania; and Christel Iffland from Ligand Pharmaceuticals.

Work supported by: Wistar Coronavirus Discovery Fund, CURE/PA Department of Health grant SAP# 4100083104, COVID/PA Department of Human Services grant SAP# 4100089371, NIH/NIAID CIVICs grant 75N93019C00051, Wistar SRA 16-4 / Inovio Pharmaceuticals, Indiana University.

Publication information: Nucleic acid delivery of immune-focused SARS-CoV-2 nanoparticles drive rapid and potent immunogenicity capable of single-dose protection, Cell Reports, 2022.