2022 Career Award Recipient: Michael Mitchell

by Melissa Pappas

Michael Mitchell (Illustration by Melissa Pappas)

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.

Read the full story in Penn Engineering Today.

Penn Medicine CAR T Therapy Expert Carl June Receives 2022 Keio Medical Science Prize

by Brandon Lausch

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.”

Read the full story in Penn Today.

June is a member of the Penn Bioengineering Graduate Group. Read more stories featuring June’s research here.

Deconstructing the Mechanics of Bone Marrow Disease

by Katherine Unger Baillie

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 PennHarvard, 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.”

Continue reading at Penn Today

Penn Medicine and Children’s Hospital of Philadelphia Announce Partnership with Costa Rica for CAR T Cell Therapy

Carl June, MD

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.’”

Read the the announcement in Penn Medicine News.

 

Penn Engineers Develop a New Method that Could Enable a Patient’s Own Antibodies to Eliminate Their Tumors

Tsourkas
Andrew Tsourkas, Ph.D.

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 in Science 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).

Exploring the History of CAR-T Cell Therapy

Carl June, MD

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.

Read “A decade of CAR-T cell therapy” in Chemistry World.

Bioengineering Graduate Jason Andrechak Wins Graduate Leadership Award

Jason Andrechak

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.

Decade-long Remission After CAR T Cell Therapy

Bill Ludwig, left, was the first patient to receive CAR T cells as part of clinical trials at Abramson Cancer Center. Carl June, right, has played a pioneering roll in the therapeutic use of CAR T cells. (Image: Penn Medicine)

Carl H. June, the Richard W. Vague Professor in Immunotherapy in Pathology and Laboratory Medicine at Penn Medicine, director of the Center for Cellular Immunotherapies and the Parker Institute for Cancer Immunotherapy, and member of the Penn Bioengineering Graduate Group at the University of Pennsylvania, has led a new analytical study published in Nature that explains the longest persistence of CAR T cell therapy recorded to date against chronic lymphocytic leukemia (CLL), and shows that the CAR T cells remained detectable at least a decade after infusion, with sustained remission in both patients. June’s pioneering work in gene therapy led to the FDA approval for the CAR T therapy (sold by Novartis as Kymriah) for treating leukemia and transforming the fight against cancer. His lab develops new forms of T cell based therapies.

Read the story in Penn Today

A New Way to Profile T Cells Can Aid in Personalized Immunotherapy

by Melissa Pappas

A scanning electron micrograph of a healthy human T cell. A better understanding the wide variety of antigen receptors that appear on the surfaces of these critical components of the immune system is necessary for improving a new class of therapies. (Credit: NIAID)

Our bodies are equipped with specialized white blood cells that protect us from foreign invaders, such as viruses and bacteria. These T cells identify threats using antigen receptors, proteins expressed on the surface of individual T cells that recognize specific amino acid sequences found in or on those invaders. Once a T cell’s antigen receptors bind to the corresponding antigen, it can directly kill infected cells or call for backup from the rest of the immune system.

We have hundreds of billions of T cells, each with unique receptors that recognize unique antigens, so profiling this T cell antigen specificity is essential in our understanding of the immune response. It is especially critical in developing targeted immunotherapies, which equip T cells with custom antigen receptors that recognize threats they would otherwise miss, such as the body’s own mutated cancer cells.

Jenny Jiang, Ph.D.

Jenny Jiang, Peter and Geri Skirkanich Associate Professor of Innovation in Bioengineering, along with lab members and colleagues at the University of Texas, Austin, recently published a study in Nature Immunology that describes their technology, which simultaneously provides information in four dimensions of T cell profiling. Ke-Yue Ma and Yu-Wan Guo, a former post doc and current graduate student in Jiang’s Penn Engineering lab, respectively, also contributed to this study.

This technology, called TetTCR-SeqHD, is the first to provide such detailed information about single T cells in a high-throughput manner, opening doors for personalized immune diagnostics and immunotherapy development.

There are many pieces of information needed to comprehensively understand the immune response of T cells, and gathering all of these measurements simultaneously has been a challenge in the field. Comprehensive profiling of T cells includes sequencing the antigen receptors, understanding how specific those receptors are in their recognition of invading antigens, and understanding T cell gene and protein expression. Current technologies only screen for one or two of these dimensions due to various constraints.

“Current technologies that measure T cell immune response all have limitations,” says Jiang. “Those that use cultured or engineered T cells cannot tell us about their original phenotype, because once you take a cell out of the body to culture, its gene and protein expression will change. The technologies that address T cell and antigen sequencing with mass spectrometry damage genetic information of the sample. And current technologies that do provide information on antigen specificity use a very expensive binding ligand that can cost more than a thousand dollars per antigen, so it is not feasible if we want to look at hundreds of antigens. There is clearly room for advancement here.”

The TetTCR-SeqHD technology combines Jiang’s previously developed T cell receptor sequencing tool, TetTCR-Seq, described in a Nature Biotechnology paper published in 2018, with the new ability of characterizing both gene and protein expression.

Read the full story in Penn Engineering Today.

Jenny Jiang on T Cell Diversity and Cancer Immunotherapy

by Melissa Pappas

Jenny Jiang, Ph.D.

Our body’s natural line of defense against infection and disease, as well as cancer, is our immune system equipped with T cells, a type of white blood cell that determines how we react to foreign substances, or antigens, in the body. While we have an arsenal of T cells to protect us from these various infections, some people lack certain T cells or simply do not have enough to fight off infections, such as the flu or HIV, or defend against the body’s own mutated cancer cells.

Understanding the diversity of T cells and which antigens they target can provide insight into developing personalized immunotherapy to help those patients with weak spots or gaps in their T cell community. Jenny Jiang, Peter and Geri Skirkanich Associate Professor of Innovation in Bioengineering, is characterizing this diversity.

Jiang recently received a Cancer Research Institute’s (CRI) Lloyd J. Old STAR grant to support her research on this topic. The CRI STAR grant identifies mid-career “Scientists TAking Risks” in innovative cancer immunotherapy research areas, providing freedom and flexibility to pursue high-risk, high-reward research with financial support of $1.25 Million over the course of five years.

Jiang spoke with CRI science writer Arthur Brodsky about her research and how the STAR grant will support it.

“In our studies of healthy individuals, who have some natural immune protection against commonly encountered viruses like the flu, we noticed that not everyone has T cells that cover all the possible antigens,” says Jiang. “There are differences in the number and types of flu-targeting T cells that each individual has. For some “exotic” antigens, like those of HIV for example, although the general population doesn’t actually have exposure to them, they should still have a very low level of minimum T cells that can offer some protection from possible future infection. So that part of our T cell arsenal acts as a safety net. But some individuals may completely lack those T cells. In those cases, as you can imagine, those people will have a hard time overcoming a future infection.”

Jiang describes how this is similar to how our bodies prevent cancerous tumor growth.

Read the full story in Penn Engineering Today.