Building a better recipe for 3D printed bones

A Johns Hopkins biomedical engineer at the School of Medicine has found that a blend of natural and man-made materials works best to create a better bone replacement with 3D printing technology. Warren Grayson, an affiliated member of Johns Hopkins Institute for NanoBioTechnology, reports his findings in the journal ACS Biomaterials Science and Engineering.

Read more below.

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A sample 3-D printed scaffold that matches the lower jaw of a female patient. (Credit: Johns Hopkins Medicine)

To make a good framework for filling in missing bone, mix at least 30 percent pulverized natural bone with some special man-made plastic and create the needed shape with a 3-D printer. That’s the recipe for success reported by researchers at The Johns Hopkins University in a paper published April 18 online in ACS Biomaterials Science & Engineering.

Each year, the Johns Hopkins scientists say, birth defects, trauma or surgery leave an estimated 200,000 people in need of replacement bones in the head or face. Historically, the best treatment required surgeons to remove part of a patient’s fibula (a leg bone that doesn’t bear much weight), cut it into the general shape needed and implant it in the right location. But, according toWarren Grayson, Ph.D., associate professor of biomedical engineering at the Johns Hopkins University School of Medicine and the report’s senior author, the procedure not only creates leg trauma but also falls short because the relatively straight fibula can’t be shaped to fit the subtle curves of the face very well.

That has led investigators to 3-D printing, or so-called additive manufacturing, which creates three-dimensional objects from a digital computer file by piling on successive, ultrathin layers of materials. The process excels at making extremely precise structures — including anatomically accurate ones — from plastic, but “cells placed on plastic scaffolds need some instructional cues to become bone cells,” says Grayson. “The ideal scaffold is another piece of bone, but natural bones can’t usually be reshaped very precisely.”

In their experiments, Grayson and his team set out to make a composite material that would combine the strength and printability of plastic with the biological “information” contained in natural bone.

They began with polycaprolactone, or PCL, a biodegradable polyester used in making polyurethane that has been approved by the FDA for other clinical uses. “PCL melts at 80 to 100 degrees Celsius (176 to 212 Fahrenheit) — a lot lower than most plastics — so it’s a good one to mix with biological materials that can be damaged at higher temperatures,” says Ethan Nyberg, a graduate student on Grayson’s team.

PCL is also quite strong, but the team knew from previous studies that it doesn’t support the formation of new bone well. So they mixed it with increasing amounts of “bone powder,” made by pulverizing the porous bone inside cow knees after stripping it of cells.

“Bone powder contains structural proteins native to the body plus pro-bone growth factors that help immature stem cells mature into bone cells,” Grayson says. “It also adds roughness to the PCL, which helps the cells grip and reinforces the message of the growth factors.”

The first test for the composite materials was printability, Grayson says. Five, 30 and 70 percent bone powder blends performed well, but 85 percent bone powder had too little PCL “glue” to maintain clear lattice shapes and was dropped from future experiments. “It was like a chocolate chip cookie with too many chocolate chips,” Nyberg says.

To find out whether the scaffolds encourage bone formation, the researchers added human fat-derived stem cells taken during a liposuction procedure to scaffolds immersed in a nutritional broth lacking pro-bone ingredients.

After three weeks, cells grown on 70 percent bone powder scaffolds showed gene activity hundreds of times higher in three genes indicative of bone formation, compared to cells grown on pure PCL scaffolds. Cells on 30 percent bone powder scaffolds showed large but less impressive increases in the same genes.

After the scientists added the key ingredient beta-glycerophosphate to the cells’ broth to enable their enzymes to deposit calcium, the primary mineral in bone, the cells on 30 percent scaffolds produced about 30 percent more calcium per cell, while those on 70 percent scaffolds produced more than twice as much calcium per cell, compared to those on pure PCL scaffolds.

Finally, the team tested their scaffolds in mice with relatively large holes in their skull bones made experimentally. Without intervention, the bone wounds were too large to heal. Mice that got scaffold implants laden with stem cells had new bone growth within the hole over the 12 weeks of the experiment. And CT scans showed that at least 50 percent more bone grew in scaffolds containing 30 or 70 percent bone powder, compared to those with pure PCL.

“In the broth experiments, the 70 percent scaffold encouraged bone formation much better than the 30 percent scaffold,” says Grayson, “but the 30 percent scaffold is stronger. Since there wasn’t a difference between the two scaffolds in healing the mouse skulls, we are investigating further to figure out which blend is best overall.”

Although the use of “decellularized” cow bone has been FDA-approved for clinical use, in future studies, the researchers say, they hope to test bone powder made from human bone since it is more widely used clinically. They also want to experiment with the designs of the scaffolds’ interior to make it less geometric and more natural. And they plan to test additives that encourage new blood vessels to infiltrate the scaffolds, which will be necessary for thicker bone implants to survive.

Other authors of the report include Ben Hung, Bilal Naved, Miguel Dias, Christina Holmes, Jennifer Elisseeff and Amir Dorafshar of the Johns Hopkins University School of Medicine.

This work was supported by the National Institute of Dental and Craniofacial Research (F31 DE024922), the Russell Military Scholar Award, the Department of Defense, the Maryland Stem Cell Research Fund and the American Maxillofacial Surgery Society Research Grant Award.

Press release by Catherine Gara; 443-287-2251; ckolf@jhmi.edu and Shawna Williams; 410-955-8236; shawna@jhmi.edu.

For media inquiries about INBT, contact Mary Spiro at mspiro@jhu.edu.

Symposium speakers 2015: Ahmet Hoke

Neuro X is the title and theme for the May 1 symposium hosted by Johns Hopkins Institute for NanoBioTechnology. The event kicks off with a continental breakfast at 8 a.m. in the Owens Auditorium, between CRB I and CRB II on the Johns Hopkins University medical campus. Talks begin at 9 a.m. Posters featuring multidisciplinary research from across many Hopkins divisions and departments will be on display from 1 p.m. to 4 p.m.

One of this year’s speakers is Ahmet Hoke MD, PhD.

Ahmet Hoke, MD, PhD

Ahme Hoke, MD, PhD

Dr. Ahmet Hoke received his medical degree from Hacettepe University in Ankara, Turkey. He then completed an internship and residency in medicine at MetroHealth Saint Luke’s Medical Center in Cleveland, OH. He completed his Ph.D. in Neuroscience at Case Western Reserve University before joining Johns Hopkins for his neurology residency. He went on to the University of Calgary for a neuromuscular fellowship. Dr. Hoke is currently a professor of Neurology and Neuroscience and the director of the Daniel B. Drachman Division of Neuromuscular Diseases at Johns Hopkins School of Medicine, where he focuses on neuromuscular diseases with a particular interest in peripheral nerve diseases. He has specialized expertise in nerve conduction studies, electromyography and nerve and muscle biopsy reading. In 2005, he received the coveted Derek Denny Brown Young Neurological Scholar Award given by the American Neurological Association to a member of the association who has achieved significant stature in neurological research and whose promise of continuing major contributions to the field of neurology is anticipated.

Dr. Hoke’s research interests includes studies on biology of peripheral axons and Schwann cells and disorders affecting the peripheral nervous system. He uses in vitro and in vivo models of peripheral neuropathies (HIV-associated sensory neuropathy, diabetic neuropathy and toxic neuropathies) to study the mechanism of axonal damage and develop therapeutic targets for drug development. In addition, he has an additional research interest focusing on mechanisms of axonal degeneration and regeneration using in vitro and in vivo models. He researches novel chemicals to treat peripheral neuropathies and utilizes engineered stem cells as therapeutic gene delivery tools to promote axonal regeneration in chronically denervated nerves as seen in nerve injuries and many degenerating disorders of the peripheral nervous system such as amyotrophic lateral sclerosis and inherited neuropathies.

Additional speakers will be profiled in the next few weeks. To register your poster and for more details visit http://inbt.jhu.edu/news/symposium/

For all press inquiries regarding INBT, its faculty and programs, contact Mary Spiro, mspiro@jhu.edu or 410-516-4802.

Symposium speakers 2015: Piotr Walczak

Neuro X is the title and theme for the May 1 symposium hosted by Johns Hopkins Institute for NanoBioTechnology. The event kicks off with a continental breakfast at 8 a.m. in the Owens Auditorium, between CRB I and CRB II on the Johns Hopkins University medical campus. Talks begin at 9 a.m. Posters featuring multidisciplinary research from across many Hopkins divisions and departments will be on display from 1 p.m. to 4 p.m.

One of this year’s speakers is Piotr Walczak, MD, PhD.

Piotr Walczak, MD, PhD

Piotr Walczak, MD, PhD

Piotr Walczak is an assistant professor in the Johns Hopkins School of Medicine Russell H. Morgan Department of Radiology and Radiological Science, Division of Magnetic Resonance (MR) Imaging. He specializes in magnetic resonance research and neuroradiology with an emphasis on stem and progenitor cell transplantation. Dr. Walczak received his MD in 2002 from the Medical University of Warsaw in Poland. He then completed a research fellowship in cell-based therapy for neurodegenerative disorders at the University of South Florida. After a fellowship in cellular imaging at Johns Hopkins University School of Medicine, Dr. Walczak joined the faculty of Johns Hopkins in 2008. He is an affiliated faculty member at the Kennedy Krieger Institute’s F.M. Kirby Research Center and the Institute for Cell Engineering.

Dr. Walczak’s research focuses primarily on noninvasively monitoring the status of stem and progenitor cells transplanted into the disease-damaged central nervous system. Stem cells are labeled with MR contrast agents, such as iron oxide nanoparticles, to precisely determine the position of the cells after transplantation. By modifying the cells using bioluminescence and MR reporter genes, as well as the use of specific promoter sequences, Dr. Walczak is working to extract information about cell survival and differentiation.

Additional speakers will be profiled in the next few weeks. To register your poster and for more details visit http://inbt.jhu.edu/news/symposium/

For all press inquiries regarding INBT, its faculty and programs, contact Mary Spiro, mspiro@jhu.edu or 410-516-4802.

Drug-chemo combo destroys challenging breast cancer stem cells

Gregg Semenza

Gregg Semenza

Researchers affiliated with Johns Hopkins Physical Sciences-Oncology Center (PS-OC) have shown that combining chemotherapy with an agent that blocks a certain cancer survival protein holds the key to fighting one of the the toughest forms of breast cancer.

Only 20 percent of patients with what are known as “triple-negative” breast cancer cells respond to chemotherapy. PS-OC associate director and Johns Hopkins professor of  medicine Gregg Semenza demonstrated in a recent study that chemotherapy actually enhances triple-negative cancer stem cell survival by switching on proteins called hypoxia-inducible factors (HIF). But when combined with currently available and FDA-approved HIF-inhibiting drugs, such as digoxin, Semenza said, chemotherapy shrank tumors.

Mice with implanted triple-negative breast cancer stem cells were treated with a combination therapy comprised of the HIF-inhibiting drug plus the chemotherapeutic drug paclitaxel. That combo treatment decreased tumor size by 30 percent more than treatment with chemotherapy. Furthermore, Semenza’s study showed that combining digoxin with the a different chemotherapeutic agent called gemcitabine “brought tumor volumes to zero within three weeks and prevented the immediate relapse at the end of treatment that was seen in mice treated with gemcitabine alone,” a press release on the study stated. Clinical trials will be needed to verify these results.

Debangshu Samanta, Ph.D., a postdoctoral fellow in the Semenza lab, was the lead author on this research published online in the Proceedings of the National Academy of Sciences. Additional authors include Daniele Gilkes, Pallavi Chaturvedi and Lisha Xiang of the Johns Hopkins University School of Medicine.

Read the PNAS article here.

Visit the PS-OC website here.

For all press inquiries regarding INBT, its faculty and programs, contact INBT’s science writer Mary Spiro, mspiro@jhu.edu or 410-516-4802.

 

Stem Cell Science, Engineering theme of May 2 symposium

Johns Hopkins Institute for Nanobiotechnology is now accepting posters for its annual symposium to be held May 2 at Owens Auditorium (located between CRB I and CRB II) at the School of Medicine. Deadline for poster registration is April 30. Top presenters are eligible to win one of three NIKON cameras.

All disciplines and topics are encouraged to register, even if not related to theme.

Go to this link for full agenda and to register.

nano-bio-symposium-14-flyer (2)The theme this year is Stem Cell Science and Engineering: State-of-the-Art. Speakers start at 9 a.m. through noon. Then at 1:30 there will be a poster session where students across Johns Hopkins will present some of their current research findings. Judges have been selected from industry and the university. Don’t miss this exciting exploration of how scientists, engineers and clinicians can work together with stem cells to solve some of humanities pressing problems in health and medicine.

This year’s speakers and talk titles include:

• 8:30-9 am Registration Lobby of Owens Auditorium

• 9:00-9:05 Welcome and Introduction of speakers Peter Searson

• 9:05-9:35 Human cell engineering: recent progress in reprogramming cell fates and editing the nuclear genome, Linzhao Cheng

• 9:35-10:05 Regenerating Musculoskeletal Tissues from Fat, Warren Grayson

• 10:05-10:35 Hitting the Bull’s Eye: Targeting HMGA1 in Cancer Stem Cells using Nanotechnology, Linda M. S. Resar

• 10:35-10:45 Coffee Break

• 10:45-11:15 Engineering biomaterials to enhance stem cell potential, Hai-Quan Mao

• 11:15 -11:45 Engineered Human Pluripotent Stem Cells for Disease Modeling Applications, Mark Powers

• 11:45-12:15 Understanding the function of risk genes for mental disorders using iPSC models, Guo-li Ming

Lunch break

• 1:30-3:30 pm Poster Sessions Owens Corridor

• 3:30 Announcement of Poster Session Winners/Adjourn

 

 

 

“Cells Performing Secret Handshake” wins grand prize

Sebastian F. Barreto, a doctoral student of chemical and biomolecular engineering in the laboratory of Sharon Gerecht, won the grand prize for his image “Cells Performing Secret Handshake” from the Regenerative Medicine Foundation. Another image that Barreto submitted received 3rd place (shown below), and a third image received honorable mention.

Late last year, RMF issued an international call for macro-photography of regenerative medicine images taken through a microscope. This inaugural contest resulted in nearly 100 images representing scientists from the United States, Australia, Canada, Germany, the Netherlands and the United Kingdom.

Cells-Performing-Secret-Handshakes

This image by Sebastian Barreto of Human Umbilical Vein Endothelial Cells “performing a secret handshake” won the grand prize in the first photo contest of the Regenerative Medicine Foundation.

Barreto’s image was included in the “Art of Science: Under the Surface” exhibition that featured an opening lecture and public reception with global expert in regenerative medicine Anthony Atala, M.D. and award winning photographer, painter and sculpture, Kelly Milukas, whose talk focused on the impact of art on healing. The winning images will also be featured in a special public patron gallery exhibition component during the Regenerative Medicine Foundation annual meeting held in San Francisco, May 5-7, 2014.

In a congratulatory letter, Joan F. Schanck, the Academic Research Program Officer, Wake Forest Institute for Regenerative Medicine and Director of Education for the Regenerative Medicine Foundation, said, “This competition will assist in developing a digital library that can be used to excite, inform and educate a broad audience.”

Barreto is affiliated with both the Johns Hopkins Institute for NanoBioTechnology and with the Physical Sciences-Oncology Center.

Captions for both photos can be found below:

Technical description for the grand prize photo: Epifluorescence image was taken at 1280 x 1024 using an Olympus BX60 microscope. Human Umbilical Vein Endothelial Cells (HUVECs) were cultured for five days and stained for F-actin (green), Vascular Endothelial cadherin (VEcad; red), and nuclei was counter-stained with DAPI (blue).

 

Endothelial-Cells-Resisting-Smooth-Muscle-Cell-Pull

Barreto’s image of endothelial cells won 3rd place in the RMF photo contest.

 

Technical description for 3rd place photo: Epifluorescence image was taken at 1280 x 1024 using an Olympus BX60 microscope. Human Endothelial Colony Forming Cells (ECFCs) were cultured for eight days before being co-cultured with human Smooth Muscle Cells (SMCs) for four more days. ECFCs were stained with CD31 (red), SMCs with SM22 (green), and nuclei was counterstained with DAPI (blue).

 

 

 

What Does This Do? Reprogramming Adult Cells to an Embryonic State

The myriad array of cell types that comprise the complex human anatomy is captivating in itself, but in my opinion, the realization that they find their roots in a single population of specialized cells is astounding. Stem cells, with the unique capacity to differentiate into mature cells and divide into identical copies without differentiating, undergo a tightly regulated developmental scheme during embryogenesis to eventually form a fully functional adult.

Although all of our fully matured cells are genetically the same, the differences in cellular functionality can be attributed to variations in gene expression. But what is a gene and what does it do?

A colony of induced pluripotent stem cells.  The colonies are grown on a feed layer which consists of mouse embryonic fibroblasts that help to maintain the stem cells in an undifferentiated state.

A colony of induced pluripotent stem cells. The colonies are grown on a feed layer which consists of mouse embryonic fibroblasts that help to maintain the stem cells in an undifferentiated state.

A molecular instruction manual or gene is a region of DNA; this gene encodes for the synthesis of proteins, which in turn become our functional molecular building blocks. There are many steps that regulate the degree of how our genetic code is transcribed and translated into protein, which are essential components in stem cell behavior.

Researchers are looking to harness the properties of stem cells for regenerative medicine applications. In addition to a steady decrease in donor organ supply as the population continues to age, complications commonly arise due to immune rejection post-surgical treatment. Through cellular therapy, stem cells can be used to replace diseased or damage tissues and organs, circumventing the current issues in surgically implanting donor organs.

Although the utilization of stem cells in a clinical setting sounds promising, both ethical and research concerns must be carefully considered. Looking through a research lens, stem cells can either be harvested from embryos or from adult sources with differing capacities to transform, namely embryonic sources can differentiate to any cell type known as pluripotency, while adult sources have limited potency.

In addition, ethical concerns arise in extracting stem cells from embryonic sources because the embryo is destroyed in the process. These challenges have led researchers to evaluate which key components directs a stem cells ability to differentiate, and if these factors can be used to coax mature cells to revert back to a stem like state with the ability to transform.

In 2012 Drs. Yamanaka and Gurdon were awarded the noble prize in Physiology and Medicine for their discoveries leading to the successful reprogramming of mature cells to stem cells by re-expressing key genes in their DNA. New techniques for controlling gene expression for inducing adult cell pluripotency are emerging with greater efficiencies, providing new strides in the success of regenerative medicine. In fact, I don’t think it’s too far fetched to imagine a day where we use our own cells for personalized disease treatment, thanks to the amazing abilities of genes, and the power to control their expression.

Quinton Smith is a second year graduate student conducting research under the advisement of Sharon Gerecht in the Department of Chemical and Biomolecular Engineering.

Mesenchymal stem cell-based therapies offer hope

Editor’s Note: The following is a summary of one of the talks from the 2013 Nano-bio Symposium hosted by Johns Hopkins Institute for NanoBioTechnology held May 17. This summary was written by Randall Meyer, a doctoral candidate in the biomedical engineering and a member of the Cancer Nanotechnology Training Center. Look for other symposium summaries on the INBT blog.

Among many of the therapies developed over the past several years, stem cells remain one of the most promising for purposes of regeneration, autoimmune disease, and cancer treatment.

Gabriele Todd of Osiris Therapeutics.

Gabriele Todd of Osiris Therapeutics.

Gabrielle Todd, a senior scientist at Osiris Therapeutics, explained some the new mesenchymal stem cell (MSC) based therapies that the company has been developing over the past several years during her talk at the annual Nano-Bio Symposium, hosted by Johns Hopkins Institute for NanoBioTechnology.

The key features that make MSCs such an attractive option is their ability to be isolated from a patient, expanded ex vivo, and re-infused into the same or possibly a different patient. Once inside the body they will home to the site of trouble and release anti-inflammatory and regenerative signals to the damaged tissue. In addition, these cells are what is known as “immune privileged,” in that they lack the necessary signals to trigger an immune response, customary in other transfusions.

Todd summarized some applications on which the company is currently working. One is an MSC-based therapy that utilizes the unique properties of these cells to treat a wide variety of immune related diseases such as graft vs. host disease, Crohn’s disease, and tissue damage from cardiac arrest to juvenile diabetes.

A second application is a product that utilizes MSCs immobilized in a membrane and applied to the site of an external wound. This cells then mediate regeneration of the external tissues, allowing for more efficient healing.

Todd reports that some of these therapies could be available on the market in the coming years.

Osiris Therapeutics, Inc. 

Pluripotent stem cells hold key to blood vessel formation

Pluripotent stem cells, those cells capable of transforming into any type of tissue in the human body, hold the key to one of science’s biggest challenges: the formation of new blood vessels.

Researchers in the laboratory of Sharon Gerecht, associate professor of chemical and biomolecular engineering in the Whiting School of Engineering at Johns Hopkins University, have demonstrated a method that causes these powerful cells to form a fresh network of blood vessels when transplanted in mice. Shawna Williams, writer at the Johns Hopkins School of Medicine, reports here on this new research, which was published online this week in the Proceedings of the National Academy of Sciences. You can find the article here.

Shown are lab-grown human blood vessel networks (red) incorporating into and around mouse networks (green). (Gerecht Lab/PNAS)

Shown are lab-grown human blood vessel networks (red) incorporating into and around mouse networks (green). (Gerecht Lab/PNAS)

Here’s a comment from Gerecht, who is affiliated with both Johns Hopkins Physical Sciences–Oncology Center and Institute for NanoBioTechnology:

“In demonstrating the ability to rebuild a microvascular bed in a clinically relevant manner, we have made an important step toward the construction of blood vessels for therapeutic use … Our findings could yield more effective treatments for patients afflicted with burns, diabetic complications and other conditions in which vasculature function is compromised.”

The Gerecht lab, in collaboration with researchers at the School of Medicine, has been working on this puzzle for some time. One important stride in this current work is that the vessels are forming and persisting in a living animal and not just in a culture in a flask.

Says lead author and doctoral student in biomedical engineering, Sravanti Kusuma:

“That these vessels survive and function inside a living animal is a crucial step in getting them to medical application.”

You can read about some of the Gerecht lab’s previous findings in this particular pursuit in the articles listed below:

Engineers Coax Stem Cells to Diversify 

Research Seeks to Turn Stem Cells into Blood Vessels

 

INBT engineers coax stem cells to diversify

Growing new blood vessels in the lab is a tough challenge, but a Johns Hopkins engineering team has solved a major stumbling block: how to prod stem cells to become two different types of tissue that are needed to build tiny networks of veins and arteries.

The team’s solution is detailed in an article appearing in the January 2013 print edition of the journal Cardiovascular Research. The article also was published recently in the journal’s online edition. The work is important because networks of new blood vessels, assembled in the lab for transplanting into patients, could be a boon to people whose circulatory systems have been damaged by heart disease, diabetes and other illnesses.

blood-vessel-3-72

Illustration by Maureen Wanjare

“That’s our long-term goal—to give doctors a new tool to treat patients who have problems in the pipelines that carry blood through their bodies,” said Sharon Gerecht, an assistant professor of chemical and biomolecular engineering who led the research team. “Finding out how to steer these stem cells into becoming critical building blocks to make these blood vessel networks is an important step.”

In the new research paper, the Gerecht team focused on vascular smooth muscle cells, which are found within the walls of blood vessels. Two types have been identified: synthetic smooth muscle cells, which migrate through the surrounding tissue, continue to divide and help support the newly formed blood vessels; and contractile smooth muscles cells, which remain in place, stabilize the growth of new blood vessels and help them maintain proper blood pressure.

To produce these smooth muscle cells, Gerecht’s lab has been experimenting with both National Institutes of Health-approved human embryonic stem cells and induced pluripotent stem cells. The induced pluripotent stem cells are adult cells that have been genetically reprogrammed to act like embryonic stem cells. Stem cells are used in this research because they possess the potential to transform into specific types of cells needed by particular organs within the body.

In an earlier study supervised by Gerecht, her team was able to coax stem cells to become a type of tissue that resembled smooth muscle cells but didn’t quite behave properly. In the new experiments, the researchers tried adding various concentrations of growth factor and serum to the previous cells. Growth factor is the “food’ that the cells consume; serum is a liquid component that contains blood cells.

“When we added more of the growth factor and serum, the stem cells turned into synthetic smooth muscle cells,” Gerecht said. “When we provided a much smaller amount of these materials, they became contractile smooth muscles cells.”

This ability to control the type of smooth muscle cells formed in the lab could be critical in developing new blood vessel networks, she said. “When we’re building a pipeline to carry blood, you need the contractile cells to provide structure and stability,” she added. “But in working with very small blood vessels, the migrating synthetic cells can be more useful.”

In cancer, small blood vessels are formed to nourish the growing tumor. The current work could also help researchers understand how blood vessels are stabilized in tumors, which could be useful in the treatment of cancer.

“We still have a lot more research to do before we can build complete new blood vessel networks in the lab,” Gerecht said, “but our progress in controlling the fate of these stem cells appears to be a big step in the right direction.”

In addition to her faculty appointment with Johns Hopkins’ Whiting School of Engineering, Gerecht is affiliated with the university’s Institute for NanoBioTechnology (INBT) and the Johns Hopkins Engineering in Oncology Center.

The lead author of the new Cardiovascular Research paper is Maureen Wanjare, a doctoral student in Gerecht’s lab who is supported both by the INBT, through a National Science Foundation Integrative Graduate Education and Research Traineeship, and by the NIH. Coauthors of the study are Gerecht and Frederick Kuo, who participated in the research as an undergraduate majoring in chemical and biomolecular engineering. The human induced pluripotent stem cells used in the study were provided by Linzhao Cheng, a hematology professor in the Johns Hopkins School of Medicine.

This research was supported by an American Heart Association Scientist Development Grant and NIH grant R01HL107938.

Original press release can be found here.