Week in BioE (August 10, 2017)

Preventing Transplant Rejection

rejection
A healthy human T cell, one of the key immune system cells.

Organ transplantation is a lifesaving measure for people with diseases of the heart, lungs, liver, and kidneys that can no longer be treated medically or surgically. The United Network for Organ Sharing, a major advocacy group for transplant recipients, reports that a new person is added to a transplant list somewhere in America every 10 minutes. However, rejection of the donor organ by the recipient’s immune system remains a major hurdle for making every transplant procedure successful. Unfortunately, the drugs required to prevent rejection have serious side effects.

To address this problem, a research team at Cornell combined DNA sequencing and informatics algorithms to identify rejection earlier in the process, making earlier intervention more likely. The team, led by Iwijn De Vlaminck of the Department of Biomedical Engineering, report in PLOS Computational Biology that a computer algorithm they developed to detect donor-derived cell-free DNA, a type of DNA shed by dead cells, in the blood of the recipient could predict heart and lung allograft rejection with a 99% correlation with the current gold standard. The earlier that signs of rejection are detected, the more likely it is that an intervention can be performed to save the organ and, more importantly, the patient.

Meanwhile, at Yale, scientists have used nanoparticles to fight transplant rejection. Publishing their findings in Nature Communications, the study authors, led by Jordan S. Pober, Bayer Professor of Translational Medicine at Yale, and Mark Saltzman, Goizueta Foundation Professor of Chemical and Biomedical Engineering, used small-interfering RNA (siRNA) to “hide” donated tissue from the immune system of the recipient. Although the ability of siRNA to hide tissue in this manner has been known for some time, the effect did not last long in the body. The Yale team used poly(amine-co-ester) nanoparticles to deliver the siRNA that extended and extended its duration of effect, in addition to developing methods to deliver to siRNA to the tissue before transplantation. The technology has yet to be tested in animals, but provides an exciting new approach to help solve the transplant rejection challenge in medicine.

Africa in Focus

A group of engineering students at Wright State University, led by Thomas N. Hangartner, professor emeritus of biomedical engineering, medicine and physics, traveled to Malawi, a small nation in southern Africa, to build a digital X-ray system at Ludzi Community Hospital. Once on site, Hangartner and his student team trained the staff to use system on patients. The group hopes they have made a significant contribution to improving the standard of care in the country, which currently allocates only 9% of its annual budget to healthcare. While the project admitted has limited impact, it’s important to bear in mind that expanding public health on a global level is a game of inches. The developing world will rise to the standards of the developed world one village at a time, one hospital at a time.

Speaking of Africa, the recent Ebola outbreak in West Africa had global implications and prompted many international organizations to identify better methods to identify early signs of outbreak. Since diseases like Ebola can spread rapidly and aggressively, detecting the outbreak early can save thousands of lives. To this end, Tony Hu of Arizona State University’s School of Biological and Health Systems Engineering has partnered with the U.S. Army to develop a platform using porous silicone nanodisks that, coupled with a mass spectrometer, could be used to detect Ebola more quickly and less expensively. In particular, by determining the strain of the Ebola virus detected, treatment could be more specifically individualized for the patient. Dr. Hu presents the technology in a video available here.

Neurotech News

Karen Moxon, professor of biomedical and mechanical engineering at the University of California, Davis, recently showed that rats with spinal injuries recovered to a more significant extent when treated with a combination of serotonergic drugs and physical therapy. Dr. Moxon found that the treatment resulted in cortical reorganization to bypass the injury. Many consider combining two different drugs to treat a disease or injury; Moxon’s clever approach used a drug in combination with the activation of cortical circuits (electroceuticals), and approach that was not considered possible with some types of spinal cord injuries.

At Stanford,  Karl Deisseroth, professor of bioengineering and of psychiatry and behavioral sciences, led a study team that recently reported in Science Translational Medicine that mice bred to have a type of autism could receive a genetic therapy that caused their brain cells to activate differently. Although the brains of the autistic mice were technically normal, the mice were unsocial and lacked curiosity. Treatment modulated expression of the CNTNAP2 gene, resulting in increased sociability and curiosity. Their findings could have tremendous implications for treating autism in humans.

Elsewhere in neurotech, Cornell announced its intention to create a neurotech research hub, using a $9 million grant from the National Science Foundation. Specializing in types of neurological imaging, the new NeuroNex Hub and Laboratory for Innovative Neurotechnology will augment the neurotech program founded at Cornell in 2015.

Academic Developments

Two important B(M)E department have developed new programs. In Montreal, McGill University has introduced a graduate certificate program in translational biomedical engineering (video here). Also at the annual meeting of the American Society for Engineering Education in Columbus, Ohio, an interdisciplinary group of scholars from Worcester Polytechnic Institute, including three professors of engineering, presented a paper entitled “The Theatre of Humanitarian Engineering.” The authors developed an experimental role-playing course in which the students developed a waste management solution for a city. According to the paper’s abstract, a core misunderstanding about engineering is the belief that it exists separately from social and political contexts. With the approach they detail, the authors believe they could address the largely unmet call for greater integration of engineering with the humanities and social sciences on the academic level.

Phillips-Cremins Research Identifies Protein Involved in Brain Development

Phillips-Cremins
Jennifer Phillips-Cremins, Ph.D.

The vast majority of genetic mutations that are associated with disease occur at sites in the genome that aren’t genes. These sequences of DNA don’t code for proteins themselves, but provide an additional layer of instructions that determine if and when particular genes are expressed. Researchers are only beginning to understand how the non-coding regions of the genome influence gene expression and might be disrupted in disease.

​​​​​​​​​​​​Jennifer Phillips-Cremins, assistant professor in the Department of Bioengineering in the University of Pennsylvania’s School of Engineering and Applied Science, studies the three-dimensional folding of the genome and the role it plays in brain development. When a stretch of DNA folds, it creates a higher-order structure called a looping interaction, or “loop.” In doing so, it brings non-coding sites into physical contact with their target genes, precisely regulating gene expression in space and time during development.

Phillips-Cremins and lab member Jonathan Beagan have led a new study identifying a new protein that connects loops in embryonic stem cells as they begin to differentiate into types of neurons. Though the study was conducted in mice, these findings inform aspects of human brain development, including how the genetic material folds in the 3-D nucleus and is reconfigured as stem cells become specialized. Better understanding of these mechanisms may be relevant to a wide range of neurodevelopmental disorders.

Cremins lab members Michael Duong, Katelyn Titus, Linda Zhou, Zhendong Cao, Jingjing Ma, Caroline Lachanski and Daniel Gillis also contributed to the study, which was published in the journal Genome Research.​​​​​​

Continue reading at the SEAS blog.

New Faculty: Interview With Konrad Kording

Kording
Konrad Kording, PhD

This week, we present our interview with incoming faculty member Konrad Kording, who starts as a Penn Integrates Knowledge Professor in the Department of Bioengineering and the Department of Neuroscience in the Perelman School of Medicine. Konrad and Andrew Mathis discuss what neuroscience is and isn’t, the “C” word (consciousness), and what it’s like for a native of Germany to live in the United States.

 

Week in BioE (August 3, 2017)

There’s news in bioengineering every week, to be sure, but the big story this past week is one that’s sure to continue appearing in headlines for days, weeks, and months — if not years — to come. This story is CRISPR-Cas9, or CRISPR for short, the gene-editing technology that many geneticists are viewing as the wave of the future in terms of the diagnosis and treatment of genetic disorders.

Standing for clustered regularly interspaced short palindromic repeats, CRISPR offers the ability to cut a cell’s genome at a predetermined location and remove and replace genes at this location. As a result, if the location is one at which the genes code for a particular disease, these genes can be edited out and replaced with healthy ones. Obviously, the implCRISPRications for this technology are enormous.

This week, it was reported that, for the first time, CRISPR was successfully used by scientists to edit the genomes of human embryos. As detailed in a paper published in Nature, these scientists edited the genomes of 50 single-cell embryos, which were subsequently allowed to undergo division until the three-day mark, at which point the multiple cells in the embryos were assessed to see whether the edits had been replicated in the new cells.  In 72% of them, they had been.

In this particular case, the gene edited out was one for a type of congenital heart defect, and the embryos were created from the eggs of healthy women and the sperm of men carrying the gene for the defect. However, the experiments prove that the technology could now be applied in other disorders.

Needless to say, the coverage of this science story has been enormous, so here is a collection of links to coverage on the topic. Enjoy!

Tsourkas Joint Venture Featured in “Inquirer”

Tsourkas
Andrew Tsourkas, Ph.D.

Andrew Tsourkas, Ph.D., who is an associate professor in the Department of Bioengineering, cofounded PolyAurum LLC, a company using gold particles to develop technologies to improve cancer therapies, in 2015. Dr. Tsourkas founded the company with two faculty members from the Perelman School of Medicine: Jay Dorsey, M.D., Ph.D., and Dave Cormode, Ph.D., the latter of whom is also a secondary factory member in BE. The name PolyAurum combines the word polymer with aurum, the Latin word for “gold.” Gold has been found to be able to enhance the effects of radiation therapy in cancer without damaging healthy tissue.

Dr. Tsourkas’s work with his colleagues at PolyAurum was featured recently in the The Philadelphia Inquirer. Debra Travers, the CEO of PolyAurum and herself a cancer survivor, was interviewed by the newspaper for its business section.

According to the article, Drs. Tsourkas and Cormode

have worked to make gold more biocompatible, resulting in PolyAurum’s current technology, Dorsey said. The gold nanocrystals are contained in a biodegradable polymer that allows enough metal to collect in a tumor. The polymer then breaks down, releasing the gold for excretion from the body so that it does not build up in key organs.

Read more at the Inquirer Web site.