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Tag: Kulp

Spotlight on Wistar COVID-19 Researcher: Daniel Kulp, Ph.D., Associate Professor 

Principal investigator Dr. Daniel Kulp is one of a group of Wistar scientists undertaking coronavirus research in response to the pandemic. A protein engineering expert, his lab focuses on rational vaccine and therapeutic antibody design for a variety of priority infectious diseases. Here he explains his interesting approach and its advantages.

The immune system is highly complex and encompasses a vast amount of cell types and compartments within the human body, therefore it can be stimulated into action in many ways. Though there is no silver bullet when it comes to vaccines, researchers have explored multiple approaches to achieve protective immunity.

Most traditional vaccines are empirically designed, meaning that a whole attenuated or killed virus is used to prompt the immune response. Thanks to a deeper knowledge of the pathogen and its mechanisms, more recent, rational approaches can be utilized to engineer specific virus-derived molecules that elicit stronger, predictable and more focused immune responses and are safer and not infectious.

In my lab, we take a bottom-up engineering approach and build precise structures into our vaccines, using computer simulations to design vaccines that help steer the immune system toward protective responses against specific pathogens. This rational approach enables us to generate improved vaccines by hypothesizing and iterating new concepts.

We specialize in designing nanovaccines, which consist of extremely small (‘nano’) particles that are similar in size and shape to bacteria and viruses and are used to display multiple copies of an antigen. Such multi-valent displays within a single vaccine can significantly enhance induced immunity.

It sounds like science fiction, but it’s not a completely new concept — in fact, the first licensed nanoparticle vaccine was against hepatitis B in 1981. The early nanoparticle vaccines were limited to nanoparticles that could be found in viruses. However, we have entered into a new era where technologies built in my lab and others have enabled us to engineer synthetic nanoparticle vaccines for a variety of infectious targets. Our unique vaccine design approach in collaboration with researchers at The Scripps Research Institute has led to the development of an HIV vaccine that has entered phase 1 clinical trials.

One of the advantages of this approach is that it is amenable to rapid delivery technologies that increases the speed at which a vaccine candidate can be advanced. So, when the new coronavirus emerged, we got to work to apply this technology and our expertise to fight SARS-CoV-2 (the virus responsible for COVID-19 disease).

A critical step in developing nanovaccines is the selection and design of the antigen to display on the nanoparticles. We choose regions of the virus called epitopes, which are crucial for the virus to function, in order to stimulate a response that can block the virus from infecting our cells.

For coronaviruses to enter host cells, fusion of the virus with the cell membrane must take place. This process is regulated by a specific part of the viral Spike protein, which adorns the surface of coronaviruses. We have engineered a nanoparticle vaccine that targets this epitope and creates robust antibody responses in mice. The lab is now ready to begin testing the vaccine in large animals before translating into the clinic.

SARS-CoV-2 possesses a receptor (like many viruses) that is another vulnerable target for protective antibodies. We have demonstrated that certain regions of the receptor for influenza and HIV could be engineered onto various self-assembling nanoparticle scaffolds. We are starting to translate these concepts to SARS-CoV-2. In addition to nanoparticle vaccines, we are beginning to engineer “decoy receptors” to trick the virus and prevent infection. The big picture is that these soluble decoys can be given to patients after they get infected to boost immune defenses and help them recover with only mild symptoms. The decoy therapies will be of critical importance to give people around the world the confidence to return from quarantine.

These approaches have big potential but can require significant monetary resources to put a vaccine or therapy through preclinical testing and the clinic, so the more support we have the faster we will be able to advance our work and potentially protect billions of vulnerable individuals worldwide.

Moving the Needle Forward: Wistar Research Leads to a Coronavirus Vaccine Entering Human Trials and Additional Wistar Coronavirus Research Projects Underway

While the world struggles with a growing number of people sickened with COVID-19 and health care workers engage in a tireless and heroic mission to save lives, biomedical researchers are on the front lines of a parallel and equally critical battle to develop new tools to effectively diagnose, treat and prevent a disease we are still learning about.

Scientists at The Wistar Institute’s Vaccine & Immunotherapy Center (VIC) have been working long hours and over weekends, devising new strategies to apply their expertise and technological platforms to combat SARS-Cov-2. 

So far, the work has paid off. The second COVID-19 vaccine to move into clinical testing in the U.S. is due in part to Wistar’s effort and comes from the team led by Dr. David Weiner and including Drs. Daniel Kulp, Ami Patel and Kar Muthumani, in collaboration with biotech company Inovio Pharmaceuticals, Inc.

This vaccine, based on synthetic DNA technology, was advanced in record time from computer design to preclinical testing in just under three months. Results from preclinical studies show the vaccine is effective at inducing both antibody and T cell-mediated responses soon after delivery in mice and guinea pigs, allowing researchers to unlock the next step — human testing subsequent to FDA approval.

Data from these studies are available to the scientific community while the manuscript is under consideration for publication in a high-impact journal.

Even though the vaccine will go through further testing in the lab as new tools and reagents become available, scientists have passed the baton to their pharmaceutical partner and the doctors and clinical experts working with the company to evaluate the safety of the coronavirus vaccine in people.

Announced by Inovio on Monday, April 6, the vaccine just entered a phase 1 clinical study coordinated by the University of Pennsylvania. 40 healthy adult participants in Philadelphia and Kansas City, Missouri will receive two vaccine doses four weeks apart, and initial data on immune responses and safety from this study are expected by late summer.

“I am extremely proud of all the work done by our scientists for this vaccine and the role played by Wistar as an academic engine of new technologies that are the basis for future medicines,” said Dario C. Altieri, M.D., Wistar president and CEO. “Hopefully, one day not so long from now, we will have a preventative vaccine to help curb the pandemic. It would be another enormous Wistar contribution to human health.”

In these times we need as many tools as possible to stem the pandemic. Wistar scientists are actively developing other vaccine approaches and therapeutic strategies, ranging from tricking the virus into attaching to decoy receptors to prevent it from infecting cells, to reducing inflammation that causes disease severity in those infected with the virus, to alternative ways to make and deliver protective antibodies that will neutralize the virus.

Although in early stages, most of this research has the potential to be advanced fairly quickly due to the nature of the approaches and our scientists’ previous experience with tackling other infectious agents.

“We are very excited about the potential of our COVID-19 vaccine,” said Weiner. “The preclinical results thus far motivate us to focus our efforts in additional directions and do our best to advance more approaches that can ultimately make a difference in this pandemic.”

To catalyze Wistar’s coronavirus research endeavor, the Institute recently launched the Wistar Coronavirus Discovery Fund, which will support a range of research programs and enhance the ability of our scientists to pursue innovative solutions as quickly as possible.

As the World Health Organization remarked, “Coronavirus research has accelerated at incredible speed…” because scientists, funders and international organizations have come together to solve the crisis. 

“We are all in this together and together we can all do our part,” said Weiner. 

Wistar Translational Research in Response to the COVID-19 Pandemic

The Wistar Institute’s Vaccine & Immunotherapy Center (VIC) has assembled its expertise in infectious disease research, as its scientists are part of a team racing to provide a countermeasure for the ongoing coronavirus outbreak. 

A historic leader with a track record of successful vaccines that have saved millions of lives, Wistar is now leveraging synthetic DNA technology to develop a vaccine against the coronavirus. 

The laboratory of Dr. David Weiner, Wistar executive vice president, director of the VIC and the W.W. Smith Charitable Trust Professor in Cancer Research, has worked for several decades advancing the technology for generating synthetic DNA vaccines that can be used for global pandemic outbreaks. 

In December 2019, Drs. Weiner, Ami Patel, Kar Muthumani, and Dan Kulp at Wistar along with colleagues at Inovio Pharmaceuticals, Inc., Drs. Joseph Kim, Laurent Humeau and Kate Broderick, were paying particular attention to the new outbreak in Wuhan, China, caused by a virus identified as a novel coronavirus. Infections were rapidly expanding in China, and by mid-January they were starting to spill over to other countries. COVID-19, as the infection was eventually named, was not going away. The team decided to work together tackling the outbreak as soon as the opportunity to jump in arose, as they have collaborated to advance vaccines for other outbreak pathogens. 

Synthetic DNA would not need the virus itself to build vaccine candidates, as these can be modeled and developed through computer analysis of the viral sequence, using predictions based on prior experience to synthesize a prototype DNA vaccine for rapid testing. The team would use their extensive MERS coronavirus vaccine experience as a model, taking into account unique features displayed by the new coronavirus in the design. In January, as the cases increased, a consortium led by Dr. Yong-Zhen Zhang of the Shanghai Public Health Clinical Center & School of Public Health posted the first viral DNA sequences online. 

“This provided the opportunity the team was waiting for,” said Dr. Weiner. Within hours, prototype vaccines were designed and moved to development.  

The designed DNA vaccine encodes a tailored sequence as the code for the vaccine. When the vaccine is administered to a recipient, the genetic sequences are then delivered inside the cells and instruct the cells to assemble a new protein shaped like a piece of the virus. Similar to using Lego blocks, a 3-D replica of a viral antigen is built inside the body and teaches the immune system what to look out for and destroy — reproducing what would happen if the person came in contact with the true virus. 

Coronaviruses are large RNA viruses that get their name from the ‘halo’ generated by the spike protein that decorates the surface of these viruses. When a coronavirus is viewed in the laboratory using electron microscopy, the spike proteins appear to form a crown. The new strain of coronavirus has been designated SARS-CoV-2 and is the entity that causes the COVID-19 disease. 

SARS-CoV-2 is an emerging pathogen that human populations have not previously experienced although it belongs to the same family as the coronaviruses that caused Severe Acute Respiratory Syndrome (SARS), an outbreak originating in China that the world experienced in the early 2000s, and Middle East Respiratory Syndrome (MERS), an outbreak originating about a decade later in the Middle East that, while controlled, still smolders. 

The team has significant experience in developing countermeasures for a coronavirus outbreak. A synthetic DNA MERS vaccine they developed advanced into phase 2 clinical study, having achieved relevant vaccine milestones including protection of laboratory animals from infection, human safety, and immunogenicity. 

The new coronavirus vaccine effort by the Weiner team is one of a handful supported by the Coalition for Epidemic Preparedness Innovations (CEPI) for the rapid development of new vaccine approaches to the coronavirus outbreak. CEPI is a global alliance led by Norway along with several other countries with major funding from philanthropic organizations. Assembled just more than three years ago to fast-track translational vaccine approaches for emerging pandemics, the organization has been comparing vaccine technologies that could be utilized rapidly in an outbreak situation with the foresight of stemming worldwide epidemics using scientific innovations through new technology. 

That preparation is being put to the test in support of developing a vaccine response for COVID-19. In January, CEPI started to discuss funding a program for clinical vaccine development with the team. On January 23, at the World Economic Forum in Davos, CEPI announced its support for three teams based on their technologies and accomplishments showing their vaccines can be rapidly created, tested, generate consistent immunity, and can be advanced in a conceptually safe fashion to clinical trials.  

Each team funded by CEPI is comprised of industry partners and academic vaccine teams that work together to move the novel candidates through early development and into clinical study and then, if applicable, advance them to efficacy trials. This approach combines the research speed of academic investigators with the focused development and clinical production and regulatory strengths of industry leaders who are at the forefront of their technologies. 

The Initial teams were: 

  • GlaxoSmithKline (GSK) in partnership with the University of Queensland, Australia, for a recombinant protein and adjuvant approach. 
  • Moderna Therapeutics, Inc., in partnership with the National Institute of Allergy and Infectious Diseases (NIAID) Vaccine Research Center for a mRNA approach; and 
  • Inovio in partnership with The Wistar Institute’s VIC team. 

Five additional teams have recently been added by CEPI.

“It’s a very unique situation — it’s the first time we’re seeing a global vaccine coordinated response like this, thanks to the speed with which CEPI acted and funded the initial teams,” said Weiner. “We are honored to be able to contribute to this important effort under the advanced DNA vaccine technology program of Inovio for COVID-19.”  

The team reported immune responses to the new synthetic DNA vaccine that were induced in several animal model species after a single immunization — the first program to do so.  

CEPI’s stated initial goal was to speed advancement of the new coronavirus vaccines to phase 1 trials in four months or less. The CEPI program has made a significant difference already in mobilizing the vaccine community to advance products for COVID-19. This week, Moderna announced that they have opened their phase 1 clinical trial. Inovio announced that a phase 1 study of the synthetic DNA vaccine is preparing to open in April.  

As of March 23, just 3.5 months into this outbreak, there are approximately 372,000 reported infections with more than 16,300 deaths spread over 168 countries. In the U.S., there are over 41,000 cases which have resulted in 573 fatalities. New York has more than 12,000 cases*.  

“The Wistar Institute’s VIC works to provide new immune approaches and understanding to impact important human disease. We need countermeasures for the COVID-19 pandemic,” said Weiner. “All of us are in this together and the more tools in the toolbox, the better equipped we are to possibly protect our vulnerable populations and our first-line defenders. Rapidly advancing these tools is only the first step in this process, but it’s an important one.”


* Source: Center for Systems Science and Engineering at Johns Hopkins University

Coupling Computational Protein Engineering with Synthetic DNA Technology Enhances Nanovaccine Efficacy Allowing the Patient’s Own Body to Customize Production

PHILADELPHIA — (March 11, 2020) — Scientists at The Wistar Institute reported a sophisticated technology to simplify production of nanovaccines, a novel approach to vaccination that can robustly stimulate immunity in preclinical models. The study, published online in the journal Advanced Science, is based on applying the synthetic DNA technology for in vivo delivery and assembly of computationally designed nanoparticles. This combination resulted in enhanced immune responses and may be explored for rapid development of vaccines and immunotherapies.

The use of nanotechnology for vaccine development has brought several advantages compared to traditional formulations. Nanovaccines consist of extremely small (nano) particles that are similar in size to bacteria and viruses and provide strong signals to the immune system. Nanovaccines produced in the laboratory are particularly good at driving antibody responses. However, laboratory production of nanoparticles can require complex formulations and purification steps that can increase costs and limit their development and rapid deployment.

“Computational modeling assists us in the rational design of nanovaccines that are capable of inducing potent levels of protective immunity, but large-scale production is challenging and lengthy,” said Daniel Kulp, Ph.D., associate professor in the Vaccine & Immunotherapy Center and corresponding author of the study. “We are excited to describe a new strategy that bypasses these challenges while also inducing more robust immune responses.”

In collaboration with the lab of David B. Weiner, Ph.D., Wistar executive vice president, director of the Vaccine & Immunotherapy Center, and the W.W. Smith Charitable Trust Professor in Cancer Research, and co-senior author on the study, Kulp and colleagues integrated computational design and synthetic DNA-mediated delivery, focusing on designing the nanovaccine particles to assemble themselves in vivo from a DNA template. They demonstrated that nanoparticles can be produced and assembled in vivo in bunches and elicit robust and specific immune responses in the vaccinated animals.

Using synthetic DNA technology, researchers were able to prompt the body to build and assemble in vivo optimized nanoparticles predesigned with the aid of computer modeling. An essential step in this process is the method of synthetic DNA delivery, called adaptive electroporation, which delivers a small current to the site of injection, enhancing DNA uptake and providing immune stimulation.

A nanoparticle vaccine for HIV that is currently in clinical trials was employed as a prototype for DNA delivery. The DNA-launched nanoparticles were successfully produced and correctly self-assembled both in vitro and in laboratory animals. The vaccines stimulated antibody responses comparable to the conventional protein-based nanoparticle vaccines, a gold standard in the field for the induction of antibody responses. However, the DNA-launched nanoparticles uniquely induced CD8+ T cell responses, engaging an important arm of immune system that mediates protection against viral antigens and surveillance against cancer.

The strategy was also successfully applied to induce potent responses with newly designed nanoparticle vaccines targeting the influenza virus protein hemagglutinin. Importantly, in a rigorous influenza challenge model, the DNA-launched hemagglutinin nanovaccine conferred significantly improved protection to mice than conventional formulations at a fraction of the dose.

“Our studies suggest that the confluence of synthetic DNA-mediated delivery and computational nanoparticle design could be a novel asset for vaccine development,” said Ziyang Xu, a Ph.D. student in the Weiner lab and first author on the study. “This approach demonstrated we can create new vaccines with improved potency and dose sparing to help global deployment of vaccines at times of critical need.”

Co-authors: Neethu Chokkalingam, Susanne Walker, Edgar Tello-Ruiz, Sarah T.C. Elliott, Alfredo Perales-Puchalt, Peng Xiao, Xizhou Zhu, Stacy Guzman, and Kar Muthumani from Wistar; Megan C. Wise, Paul D. Fisher, Katherine Schultheis, Eric Schade, Kate E. Broderick, and Laurent M. Humeau from Inovio Pharmaceuticals; Ruth A. Pumroy and Vera Moiseenkova-Bell from University of Pennsylvania; Sergey Menis and William R. Schief from The Scripps Research Institute; and Hanne Andersen from Bioqual Inc.

Work supported by: National Institutes of Health (NIH) grants U19 Al109646-04, R01 GM103899, R01 GM129357 and a Collaborative Influenza Vaccine Innovation Centers (CIVICs) grant;
Grants from the Bill & Melinda Gates Foundation, Inovio Pharmaceuticals, W.W. Smith Charitable Trust, and the Monica H.M. Shander Memorial Fellowship. Core support for The Wistar Institute was provided by the Cancer Center Support Grant P30CA010815.

Publication information: In vivo assembly of nanoparticles achieved through synergy of structure-based protein engineering and synthetic DNA generates enhanced adaptive immunity, Advanced Science, 2020. In press.