Perelman School of Medicine (PSOM) professors and Penn Bioengineering Graduate Group members Carl June and Avery Posey are leading the charge in T cell therapy and the fight against cancer.
Avery Posey, PhDCarl June, MD
Advances in genome editing through processes such as CRISPR, and the ability to rewire cells through synthetic biology, have led to increasingly elaborate approaches for modifying and supercharging T cells for therapy. Avery Posey, Assistant Professor of Pharmacology, and Carl June, the Richard W. Vague Professor in Immunotherapy, explain how new techniques are providing tools to counter some of the limitations of current CAR T cell therapies in a recent Nature feature.
The pair were also part of a team of researchers from PSOM, the Children’s Hospital of Philadelphia (CHOP), and the Corporal Michael J. Crescenz VA Medical Center to receive an inaugural $8 million Therapy ACceleration To Intercept CAncer Lethality (TACTICAL) Award from the Prostate Cancer Foundation. Their project will develop new clinic-ready CAR T cell therapies for Metastatic Castrate-Resistant Prostate Cancer (mCRPC).
Engineers in the Center for Precision Engineering for Health (CPE4H) are focusing on innovations in diagnostics and delivery, cellular and tissue engineering, and the development of new devices that integrate novel materials with human tissues. Below is an excerpt from “Going Small to Win Big: Engineering Personalized Medicine,” featuring the research from the laboratory of Jenny Jiang, J. Peter and Geri Skirkanich Associate Professor of Innovation in Bioengineering.
The Challenge
In order to create personalized immune therapies, researchers need to untangle what is happening between an individual patient’s immune cells and the antigens that they interact with on a molecular level. Immune cell-antigen interactions need to be understood in four different areas in order to create a full picture: the unique genetic sequence of the T cell’s antigen receptors, the antigen specificity of that cell, and both the gene and protein expression of the same cell.
The Status Quo
Prior methods of understanding interactions between T cells and antigens could only get a picture of one or two of these four elements because of technology constraints. Other roadblocks included that cells cultured or engineered in a laboratory setting are not in a natural environment so they won’t express genes or proteins in the way T cells would in the body, and technologies that assess the antigen specificity of T cells were not cost-effective for looking at large numbers of antigens.
The Jiang Lab’s Fix
The lab of Jenny Jiang, J. Peter and Geri Skirkanich Associate Professor of Innovation in Bioengineering, developed a technology called TetTCR-SeqHD, which solves these problems. Using this technology, scientists can now simultaneously profile samples of large numbers of single T cells in the four dimensions using high- throughput screening.
The Jiang Lab’s technology is essentially a method for getting a “full-body scan” of an individual’s T cells and creates a catalog of the different types of T cells and the antigens they respond (or don’t respond) to, paving the way for the ability to better target immune therapies to an individual patient.
“Individual T cells are unique, and that’s the challenge of using one treatment to fit all,” says Jiang. “Identifying antigen specificity and creating therapies that target that specificity in an individual’s T cells will be key to truly personalizing immune therapies in the future.”
Penn Medicine researchers laud the early results for CAR T therapy in lupus patients, which point to broader horizons for the use of personalized cellular therapies.
Penn Medicine’s Carl June and Daniel Baker.
Engineered immune cells, known as CAR T cells, have shown the world what personalized immunotherapies can do to fight blood cancers. Now, investigators have reported highly promising early results for CAR T therapy in a small set of patients with the autoimmune disease lupus. Penn Medicine CAR T pioneer Carl June and Daniel Baker, a doctoral student in cell and molecular biology in the Perelman School of Medicine, discuss this development in a commentary published in Cell.
“We’ve always known that in principle, CAR T therapies could have broad applications, and it’s very encouraging to see early evidence that this promise is now being realized,” says June, who is the Richard W. Vague Professor in Immunotherapy in the department of Pathology and Laboratory Medicine at Penn Medicine and director of the Center for Cellular Immunotherapies at the Abramson Cancer Center.
T cells are among the immune system’s most powerful weapons. They can bind to, and kill, other cells they recognize as valid targets, including virus-infected cells. CAR T cells are T cells that have been redirected, through genetic engineering, to efficiently kill specifically defined cell types.
CAR T therapies are created out of each patient’s own cells—collected from the patient’s blood, and then engineered and multiplied in the lab before being reinfused into the patient as a “living drug.” The first CAR T therapy, Kymriah, was developed by June and his team at Penn Medicine, and received Food & Drug Administration approval in 2017. There are now six FDA-approved CAR T cell therapies in the United States, for six different cancers.
From the start of CAR T research, experts believed that T cells could be engineered to fight many conditions other than B cell cancers. Dozens of research teams around the world, including teams at Penn Medicine and biotech spinoffs who are working to develop effective treatments from Penn-developed personalized cellular therapy constructs, are examining these potential new applications. Researchers say lupus is an obvious choice for CAR T therapy because it too is driven by B cells, and thus experimental CAR T therapies against it can employ existing anti-B-cell designs. B cells are the immune system’s antibody-producing cells, and, in lupus, B cells arise that attack the patient’s own organs and tissues.
Michael Mitchell, J. Peter and Geri Skirkanich Assistant Professor of Innovation in the Department of Bioengineering, is one of this year’s recipients of the National Science Foundation’s CAREER Award. The award is given to early-career faculty researchers who demonstrate the potential to be role models in their field and invest in the outreach and education of their work.
Mitchell’s award will fund research on techniques for “immunoengineering” macrophages. By providing new instructions to these cells via nanoparticles laden with mRNA and DNA sequences, the immune system could be trained to target and eliminate solid tumors. The award will also support graduate students and postdoctoral fellows in his lab over the next five years.
The project aligns with Mitchell’s larger research goals and the current explosion of interest in therapies that use mRNA, thanks to the technological breakthroughs that enabled the development of COVID-19 vaccines.
“The development of the COVID vaccine using mRNA has opened doors for other cell therapies,” says Mitchell. “The high-priority area of research that we are focusing on is oncological therapies, and there are multiple applications for mRNA engineering in the fight against cancer.”
A new wave of remarkably effective cancer treatments incorporates chimeric antigen receptor T-cell (CAR-T) therapy. There, a patient’s T-cells, a type of white blood cell that fights infections, are genetically engineered to identify, target and kill individual cancer cells that accumulate in the circulatory system.
However, despite CART-T therapy’s success in treating certain blood cancers, the approach is not effective against cancers that form solid tumors. Because T-cells are not able to penetrate tumors’ fibrous barriers, Mitchell and his colleagues have turned to another part of the immune system for help.
The award from Japan’s oldest private university honors outstanding contributions to medicine and life sciences.
Richard W. Vague Professor in Immunotherapy Carl June.
Carl June,the Richard W. Vague Professor in Immunotherapy in the department of Pathology and Laboratory Medicine in the Perelman School of Medicine and director of the Center for Cellular Immunotherapies at Penn’s Abramson Cancer Center, has been named a 2022 Keio Medical Science Prize Laureate. He is recognized for his pioneering role in the development of CAR T cell therapy for cancer, which uses modified versions of patients’ own immune cells to attack their cancer.
The Keio Medical Science Prize is an annual award endowed by Keio University, Japan’s oldest private university, which recognizes researchers who have made an outstanding contribution to the fields of medicine or the life sciences. It is the only prize of its kind awarded by a Japanese university, and eight laureates of this prize have later won the Nobel Prize. Now in its 27th year, the prize encourages the expansion of researcher networks throughout the world and contributes to the well-being of humankind.
“Dr. June exemplifies the spirit of curiosity and fortitude that make Penn home to so many ‘firsts’ in science and medicine,” said Penn President Liz Magill. “His work provides hope to cancer patients and their families across the world, and inspiration to our global community of physicians and scientists who are working to develop the next generation of treatments and cures for diseases of all kinds.”
Acollaborative team developed an alginate-based hydrogel system that mimics the viscoelasticity of the natural extracellular matrix in bone marrow. By tweaking the balance between elastic and viscous properties in these artificial ECMs, they could recapitulate the viscoelasticity of healthy and scarred fibrotic bone marrow, and study the effects on human monocytes placed into these artificial ECMs. (Image: Adam Graham/Harvard CNS/Wyss Institute at Harvard University)
Fibrosis is the thickening of various tissues caused by the deposition of fibrillar extracellular matrix (ECM) in tissues and organs as part of the body’s wound healing response to various forms of damage. When accompanied by chronic inflammation, fibrosis can go into overdrive and produce excess scar tissue that can no longer be degraded. This process causes many diseases in multiple organs, including lung fibrosis induced by smoking or asbestos, liver fibrosis induced by alcohol abuse, and heart fibrosis often following heart attacks. Fibrosis can also occur in the bone marrow, the spongy tissue inside some bones that houses blood-producing hematopoietic stem cells (HSCs) and can lead to scarring and the disruption of normal functions.
Chronic blood cancers known as “myeloproliferative neoplasms” (MPNs) are one example, in which patients can develop fibrotic bone marrow, or myelofibrosis, that disrupts the normal production of blood cells. Monocytes, a type of white blood cell belonging to the group of myeloid cells, are overproduced from HSCs in neoplasms and contribute to the inflammation in the bone marrow environment, or niche. However, how the fibrotic bone marrow niche itself impacts the function of monocytes and inflammation in the bone marrow was unknown.
Now, a collaborative team from Penn, Harvard, the Dana-Farber Cancer Institute (DFCI), and Brigham and Women’s Hospital has created a programmable hydrogel-based in vitro model mimicking healthy and fibrotic human bone marrow. Combining this system with mouse in vivo models of myelofibrosis, the researchers demonstrated that monocytes decide whether to enter a pro-inflammatory state and go on to differentiate into inflammatory dendritic cells based on specific mechanical properties of the bone marrow niche with its densely packed ECM molecules. Importantly, the team found a drug that could tone down these pathological mechanical effects on monocytes, reducing their numbers as well as the numbers of inflammatory myeloid cells in mice with myelofibrosis. The findings are published in Nature Materials.
“We found that stiff and more elastic slow-relaxing artificial ECMs induced immature monocytes to differentiate into monocytes with a pro-inflammatory program strongly resembling that of monocytes in myelofibrosis patients, and the monocytes to differentiate further into inflammatory dendritic cells,” says co-first author Kyle Vining, who recently joined Penn’s School of Dental Medicine and School of Engineering and Applied Science as an assistant professor of preventive and restorative sciences. “More viscous fast-relaxing artificial ECMs suppressed this myelofibrosis-like effect on monocytes. This opened up the possibility of a mechanical checkpoint that could be disrupted in myelofibrotic bone marrow and also may be at play in other fibrotic diseases.”
Vining worked on the study as a postdoctoral fellow at Harvard in the lab of David Mooney. “Our study shows that the differentiation state of monocytes, which are key players in the immune system, is highly regulated by mechanical changes in the ECM they encounter,” says Mooney, who co-led the study with DFCI researcher Kai Wucherpfennig. “Specifically, the ECM’s viscoelasticity has been a historically under-appreciated aspect of its mechanical properties that we find correlates strongly between our in vitro and the in vivo models and human disease. It turns out that myelofibrosis is a mechano-related disease that could be treated by interfering with the mechanical signaling in bone marrow cells.”
Carl June, MD, Professor in the Perelman School of Medicine and member of the Penn Bioengineering Graduate Group, was quoted in a recent press release announcing a new international partnership between Penn Medicine (PSOM), the Children’s Hospital of Pennsylvania (CHOP), and Costa Rica’s CCSS, or the Caja Costarricense de Seguro Social (Social Security Program), to develop CAR T research in Costa Rica. June is a world renowned cancer cell therapy pioneer whose research led to the initial development and FDA approval of CAR T cell therapy:
“‘At least 15,000 patients across the world have received CAR T cells, and dozens more clinical trials using this approach are in progress, for almost every major tumor type, but people in many parts of the globe still do not have access to treatment with these transformative therapies,’ said Carl H. June, MD, the Richard W. Vague Professor in Immunotherapy and director of the Center for Cellular Immunotherapies in Penn’s Perelman School of Medicine. “We are honored to work with our colleagues in Costa Rica in hopes of building a path for patients in underserved areas to have the opportunity to benefit from clinical research programs offering this personalized therapy.’”
One of the reasons that cancer is notoriously difficult to treat is that it can look very different for each patient. As a result, most targeted therapies only work for a fraction of cancer patients. In many cases, patients will have tumors with no known markers that can be targeted, creating an incredible challenge in identifying effective treatments. A new study seeks to address this problem with the development of a simple methodology to help differentiate tumors from healthy, normal tissues.
This new study, published inScience Advances, was led by Andrew Tsourkas, Professor in Bioengineering and Co-Director of the Center for Targeted Therapeutics and Translational Nanomedicine (CT3N), who had what he describes as a “crazy idea” to use a patient’s antibodies to find and treat their own tumors, taking advantage of the immune system’s innate ability to identify tumors as foreign. This study, spearheaded by Burcin Altun, a former postdoctoral researcher in Tsourkas’s lab, and continued and completed by Fabiana Zappala, a former graduate student in Penn Bioengineering, details their new method for site-specifically labeling “off-the-shelf” and native serum autoantibodies with T cell–redirecting domains.
Researchers have known for some time that cancer patients will generate an antibody response to their own tumors. These anti-tumor antibodies are quite sophisticated in their ability to specifically identify cancer cells; however, they are not sufficiently potent to confer a therapeutic effect. In this study, Tsourkas’s team converted these antibodies into bispecific antibodies, thereby increasing their potency. T cell-redirecting bispecific antibodies are a new form of targeted therapeutic that forms a bridge between tumor cells and T cells which have been found to be as much as a thousand-times more potent than antibodies alone. By combining the specificity of a patient’s own antibodies with the potency of bispecific antibodies, researchers can effectively create a truly personalized therapeutic that is effective against tumors.
In order to test out this new targeted therapeutic approach, the Tsourkas lab had to develop an entirely new technology, allowing them to precisely label antibodies with T cell targeting domains, creating a highly homogeneous product. Previously it has not been possible to convert native antibodies into bispecific antibodies, but Tsourkas’s Targeted Imaging Therapeutics and Nanomedicine or TITAN lab specializes in the creation of novel targeted imaging and therapeutic agents for detection and treatment of various diseases. “Much is yet to be done before this could be considered a practical clinical approach,” says Tsourkas. “But I hope at the very least this works stimulates new ideas in the way we think about personalized medicine.”
In their next phase, Tsourkas’s team will be working to separate anti-tumor antibodies from other antibodies found in patients’ serum (which could potentially redirect the bispecific antibodies to other locations in the body), as well as examining possible adverse reactions or unintended effects and immunogenicity caused by the treatment. However, this study is just the beginning of a promising new targeted therapeutic approach to cancer treatment.
This work was supported by Emerson Collective and the National Institutes of Health, National Cancer Institute (R01 CA241661).
A new feature in Chemistry World explores the history of CAR (chimeric antigen receptor)-T cell therapy, a revolutionary type of therapeutic treatment for certain types of cancer. One of the pioneers of CAR-T cell therapy is Carl June, Richard W. Vague Professor in Immunotherapy in the Perelman School of Medicine and member of the Penn Bioengineering Graduate Group. His groundbreaking research opened the door for FDA approval of the CAR T therapy called Kymriah, which treats acute lymphoblastic leukemia (ALL), one of the most common childhood cancers.
Congratulations to recent Penn Bioengineering graduate Jason Andrechak on winning a Graduate Leadership Awards for 2022. Each year a select number of students across the university are recognized for their service and lasting contributions to graduate student life at Penn. Andrechak, one of only ten recipients in 2022, won a Dr. Andy Binns Award for Outstanding Service to Graduate and Professional Student Life. This award is presented to “graduate or professional students, upon their graduation from Penn, who have significantly impacted graduate and professional student life through service involvement in student life initiatives or organizations.” Andrechak won this award for his “service and leadership in advocating for equity and accessibility during the transition to virtual operations and following a period of leadership transition within the Graduate and Professional Student Assembly (GAPSA). ”
Andrechak completed his Ph.D. in Bioengineering in 2022, where he studied macrophage immunotherapy in solid tumors in the lab of Dennis E. Discher, Robert D. Bent Professor in Chemical and Biomolecular Engineering, Bioengineering, and Mechanical Engineering and Applied Mechanics. He was named a National Science Foundation Graduate Research Fellow in 2018. He has actively led the Graduate Association of Bioengineers (GABE) as Community Service & Outreach chair from 2017-2019 and as co-President from 2019-2022. He also served as the Director of Equity & Access for the Graduate & Professional Student Assembly (GAPSA) from 2020-2021, in addition to several other service and advisory roles at the department, school, and university levels.
Learn more about the Penn Graduate Leadership Awards and read the full list of recipients on the Grad Center at Penn website.
