Robert L. Mauck, Ph.D.

The tension-activated repair patch used in animal trials plugs holes in discs in the spine like car tire patches and could prevent further disease progression

A new biologic “patch” that is activated by a person’s natural motion could be the key to fixing herniated discs in people’s backs, according to researchers at the Perelman School of Medicine at the University of Pennsylvania and the CMC VA Medical Center (CMCVAMC). Combining years of work from many different projects, the “tension-activated repair patches” (TARPs) provide controlled release of an anti-inflammatory molecule called anakinra from microcapsules over time, which helped discs in a large animal model regain the tension they need to reverse herniation and prevent further degeneration. This pre-clinical research is detailed in a paper published today in Science Translational Medicine.

“Currently there is no curative treatment for disc herniation, and the best thing out there is just like sticking a plain rubber plug into a hole in a tire. It will stay for a while but it won’t make a great seal,” said co-senior author Robert Mauck, PhD, a professor in Orthopaedic Surgery and director of the McKay Laboratory for Orthopaedic Surgery Research at Penn and research career scientist and co-director of the Translational Musculoskeletal Research Center at the CMCVAMC… Continue reading.

Imagine you’re trying to do a job and all of the information you need to do it is in a few books at the library. Except, those books are randomly arranged along with all the other books on shelves across the whole building. Without that vital information from the books you were looking for, you wouldn’t perform your job very well.

This is the situation that researchers at the Perelman School of Medicine at the University of Pennsylvania found when they studied the nucleus of cells inside connective tissues deteriorating as a result of tendinosis. Disease-related disruptions in the environments that cells exist in caused the re-organization of the genome – which is the sum of an organism’s DNA sequences – inside the cell’s nucleus, changing the way cells functioned and making them unable to reorder their DNA information in the right way again. These findings, published today in Nature Biomedical Engineering, point to the possibility of new treatments – such as small-molecule therapies – to bring in a sort of librarian that could restore order to the affected cells… Continue reading.

According to a recent animal-based study performed by scientists from the Perelman School of Medicine at the University of Pennsylvania, a novel biosealant therapy could help stabilize injuries that cause the disintegration of cartilage tissues, opening the door for a future fix or—even better—start working directly with new cells to improve healing.

The researchers’ study was reported in the Advanced Healthcare Materials journal.

Our research shows that using our hyaluronic acid hydrogel system at least temporarily stops cartilage degeneration that commonly occurs after injury and causes pain in joints. In addition to pausing cartilage breakdown, we think that applying this therapy can present a surface that is ‘sticky’ for cells, such as stem cells that are routinely injected into joints to counteract injury. This reinforcing hydrogel could actually synergize with those cells to create a long-term solution… Continue reading.

Scientists at the Perelman School of Medicine at the University of Pennsylvania used a magnetic field and hydrogels to demonstrate a new possible way to rebuild complex body tissues, which they say could result in more lasting fixes to common injuries, such as cartilage degeneration.

Their study “Magneto‐Driven Gradients of Diamagnetic Objects for Engineering Complex Tissues” appears in Advanced Materials.

“Engineering complex tissues represents an extraordinary challenge and, to date, there have been few strategies developed that can easily recapitulate native‐like cell and biofactor gradients in 3D materials. This is true despite the fact that mimicry of these gradients may be essential for the functionality of engineered graft tissues. Here, a non‐traditional magnetics‐based approach is developed to predictably position naturally diamagnetic objects in 3D hydrogels,” write the investigators… Continue reading.

Some of the most common traits among patients with cartilage issues in the knee are excluding them from participating in clinical trials because the trial outcomes might not yield the optimum results for new methods of cartilage regeneration, according to a Penn Medicine study published in Regenerative Medicine. Researchers testing the new methods tend to only include the patients most likely to succeed with the fewest complications, but if some of these trials could be safely opened up to different kinds of patients — such as those older than 55 or younger than 18, or those who knee joints don’t align perfectly — the results could be much more robust and reflective of the patient population being treated. In the team’s paper, they also highlighted therapies that hold special promise for the excluded populations, such as the use of “scaffolding” to promote cartilage growth… Continue reading.

Scientists have moved a step closer to being able to replace degenerated spinal discs with new ones grown in a laboratory from a patient’s own stem cells.

Spinal discs are soft tissues that cushion the vertebrae and enable our backs to conform and perform the tasks of everyday movement. Over time, the discs can wear out and cause the bones of the spine to rub together and pinch nerves. This disc degeneration is one of the leading causes of back pain.

University of Pennsylvania researchers reported in the journal Science Translational Medicine that they have successfully grown and implanted replacement discs made from the stem cells of goats. The cells were grown in a laboratory in a disc shaped form and then implanted into the necks of goats… Continue reading.

PHILADELPHIA – A new biomaterial can be used to study how and when stem cells sense the mechanics of their surrounding environment, found a team led by Robert Mauck, PhD, the Mary Black Ralston Professor for Education and Research in Orthopaedic Surgery, in the Perelman School of Medicine at the University of Pennsylvania. With further development, this biomaterial could be used to control when immature stem cells differentiate into more specialized cells for regenerative and tissue-engineering-based therapies. Their study appears as an advance online publication in Nature Materials this month. 

During early development in an embryo, the progenitor cells of many types of musculoskeletal tissue start out in close contact to each other and over time transition into an organized network of individual cells surrounded by an extracellular matrix. Throughout the course of embryo development, the it gets stiffer due to increased amounts of matrix material and crosslinking during early development in an embryo, the progenitor cells of many types of musculoskeletal tissue start out in close contact to each other and over time transition into an organized network of individual cells surrounded by an extracellular matrix (ECM). This matrix is made up of polysaccharides and fibrous proteins secreted by cells, providing structural and biochemical support to the cells within.

Throughout the course of embryo development, the ECM gets stiffer due to increased amounts of matrix material and crosslinking, eventually guiding stem cells to develop into more specialized cells across various tissue types. It also acts as a medium through which mechanical information is transmitted to cells (such as forces generated with such normal activities as walking or running).

LAS VEGAS — Robert L. Mauck, PhD, an associate professor of Orthopaedic Surgery at the Perelman School of Medicine at the University of Pennsylvania, is one of four scientists given awards by the Kappa Delta Sorority and the Orthopaedic Research and Education Foundation at the 2015 Annual Meeting of the American Academy of Orthopaedic Surgeons in Las Vegas. Awardees are chosen for their outstanding basic science and clinical research related to musculoskeletal disease or injury, with the ultimate goal of advancing patient treatment and care. Each award carries a $20,000 stipend.

Mauck received the 2015 Kappa Delta Young Investigator Award for his research on developing and optimizing nanofibrous scaffolds — extremely small, bioengineered materials — to repair or replace complex connective tissues, such as those that make up the meniscus of the knee joint or the intervertebral disc of the spinal column.

“This is quite an honor, given the number of fantastic scientists and research teams that have won this award in the past,” said Mauck. “It is really a reflection of many years of hard work by all of the great people who have worked with me over to develop novel regenerative approaches to solve the difficult problem of dense connective tissue repair.”

Bioengineers are a step closer to growing new cartilage from a patient’s own stem cells.

Cartilage injuries are difficult to repair. Current surgical options generally involve taking a piece from another part of the injured joint and patching over the damaged area, but this approach involves damaging healthy cartilage, and a person’s cartilage may still deteriorate with age.

“The broad picture is trying to develop new therapies to replace cartilage tissue, starting with focal defects—things like sports injuries—and then hopefully moving toward surface replacement for cartilage degradation that comes with aging,” says Jason Burdick, associate professor of bioengineering at the University of Pennsylvania. “Here, we’re trying to figure out the right environment for adult stem cells to produce the best cartilage.”

“As we age, the health and vitality of cartilage cells declines,” says Robert Mauck, associate professor of orthopedic surgery, “so the efficacy of any repair with adult chondrocytes is actually quite low.  Stem cells, which retain this vital capacity, are therefore ideal.”

Cartilage injuries are difficult to repair. Current surgical options generally involve taking a piece from another part of the injured joint and patching over the damaged area, but this approach involves damaging healthy cartilage, and a person’s cartilage may still deteriorate with age.

Bioengineers are interested in finding innovative ways to grow new cartilage from a patient’s own stem cells, and, thanks to a new study from the University of Pennsylvania, such a treatment is a step closer to reality.  

The research was conducted by associate professor Jason Burdick of the Department of Bioengineering in the School of Engineering and Applied Science and associate professor Robert Mauck of the Department of Orthopaedic Surgery in Penn’s Perelman School of Medicine. Liming Bian and Murat Guvendiren, members of Burdick’s lab, also took part.

It was published in the Proceedings of the National Academy of Sciences.

“The broad picture,” Burdick said, “is trying to develop new therapies to replace cartilage tissue, starting with focal defects — things like sports injuries — and then hopefully moving toward surface replacement for cartilage degradation that comes with aging. Here, we’re trying to figure out the right environment for adult stem cells to produce the best cartilage.”    

“As we age, the health and vitality of cartilage cells declines,” Mauck said, “so the efficacy of any repair with adult chondrocytes is actually quite low. Stem cells, which retain this vital capacity, are therefore ideal.”

Bioengineered replacements for tendons, ligaments, the meniscus of the knee, and other tissues require re-creation of the exquisite architecture of these tissues in three dimensions. These fibrous, collagen-based tissues located throughout the body have an ordered structure that gives them their robust ability to bear extreme mechanical loading.

Many labs have been designing treatments for ACL and meniscus tears of the knee, rotator cuff injuries, and Achilles tendon ruptures for patients ranging from the weekend warrior to the elite Olympian. One popular approach has involved the use of scaffolds made from nano-sized fibers, which can guide tissue to grow in an organized way. Unfortunately, the fibers’ widespread application in orthopaedics has been slowed because cells do not readily colonize the scaffolds if fibers are too tightly packed.

Robert L. Mauck, PhD, professor of Orthopaedic Surgery and Bioengineering, and Brendon M. Baker, PhD, previously a graduate student in the Mauck lab at the Perelman School of Medicine, University of Pennsylvania, have developed and validated a new technology in which composite nanofibrous scaffolds provide a loose enough structure for cells to colonize without impediment, but still can instruct cells how to lay down new tissue. Their findings appear online this week in the Proceedings of the National Academy of Sciences.