Meet INBT’s summer interns, already digging into their research

Research does not take a holiday during the summer at Johns Hopkins University in Baltimore, Md. In fact, it ramps up with the addition of many new faces from across the country.

The Johns Hopkins Institute for NanoBioTechnology summer research interns have arrived and are already busy at work in various laboratories. This year’s group is the largest the institute has ever hosted, with 17 undergraduates from universities nationwide.

Of the total, three students are affiliated with the Center of Cancer Nanotechnology Excellence and four are affiliated with the Physical Sciences-Oncology Center. The remaining 10 are part of the National Science Foundation Research Experience for Undergraduates program. All are hosted through INBT, which serves as a hub for their academic and social activities.

INBT summer interns conduct 10 weeks of research in a laboratory either on the Homewood or the medical campus of the University. At the end of that time, students have learned how to work in a multidisciplinary team and how to manage a short term research project.  They also discover if research is a pathway they want to pursue after earning their bachelor’s degrees.

In August, interns from many of the science, medicine, engineering and public health summer programs will gather for a  poster session to be held on August 2 at 3 p.m. in Turner Concourse. The poster session will allow students to show off the results of their their work.

This year’s INBT/PS-OC/CCNE interns include:

At the Whiting School of Engineering…

Amani Alkayyali from Wayne State University is an REU student in the laboratory of Honggang Cui assistant professor in the Department of Chemical and Biomolecular Engineering. Also in the Cui lab are CCNE intern Matthew Fong from the University of California, Berkeley and Michelle LaComb, an REU student from Rice University.

Sharon Gerecht, assistant professor in the Department of Chemical and Biomolecular engineering, is hosting three interns. Josh Porterfield of Cornell University and Carolyn Zhang from the University of California, San Diego are both PS-OC interns, and Bria Macklin of Howard University is an REU intern.

Jacqueline Carozza of Cornell University is a PS-OC student working in the lab of Denis Wirtz, professor in the Department Chemical and Biomolecular Engineering. Cassandra Loren from Oregon State University is a PS-OC intern also working in the Wirtz lab.

Eric Do from the University of Washington is an REU working in the lab of assistant professor Margarita Herrara-Alonso in the Department of Materials Science and Engineering.

Olivia Hentz from Cornell is an REU student working in the lab of Jonah Erlebacher, professor in the Department of Materials Science and Engineering.

Justin Samorajski from the University of Dallas is a returning summer intern, once again working in the materials science and engineering lab of professor Peter Searson as part of the CCNE.

At the School of Medicine…

Lauren Lee of Cornell University is an REU working in the lab of biomedical engineering lab of associate professor Hai-Quan Mao.

Albert Lu from the University of California Berkeley is a CCNE intern working in the biomedical engineering lab of associate professor Jeff Wang.

Bianca Lascano from Norfolk State University is an REU in assistant professor Jordan Green’s biomedical engineering lab.

Charlie Nusbaum of the Richard Stockton College is an REU intern in the radiation oncology lab of assistant professor Robert Ivkov.

At the Krieger School of Arts and Sciences…

Anthony Loder of Rowan University is an REU working in the biology lab of assistant professor Xin Chen.

Daniel McClelland is also REU from Bethany College works in the chemistry laboratory of professor Howard Fairbrother.

 

 

Heart scar tissue may take active role in promoting deadly arrhythmias

Susan Thompson, PhD student in biomedical engineering, and Craig Copeland, PhD student in physics and astronomy, observe a single non-beating heart cell called a myofibroblast growing on a micropost device. (Photo Jay VanRensselaer)

Johns Hopkins University biomedical engineers and physicists affiliated with the Institute for NanoBioTechnology have completed a study that suggests that mechanical forces exerted by cells that build scar tissue following a heart attack may later disrupt rhythms of beating heart cells and trigger deadly arrhythmias. Their findings, published in a recent issue of the journal Circulation, could result in a new target for heart disease therapies.

Principal investigator Leslie Tung, a School of Medicine professor in the department of biomedical engineering, led a team that looked at how heart cells that beat (called “cardiomyocytes”) were affected by the non-beating cells (called “myofibroblasts”). Myofibroblasts are called to arms at the site of injury following a heart attack.

“The role of the myofibroblast (non-beating cells) is to make the injured area as small as possible. Through contraction, the myofibroblasts close the wound and lay down a protein matrix to reduce the scar area,” said lead investigator Susan Thompson, a pre-doctoral fellow in Tung’s Cardiac Bioelectric Systems Laboratory. “In doing so, the myofibroblasts pull on the membranes of adjacent cardiomyocytes. We found that these forces were strong enough to decrease the electrical activity of the working heart cells through mechanical coupling.”

Thompson electrically stimulated cultures containing both the beating and non-beating cells growing together, and found that when the electrical impulses occurred, the non-beating myofibroblasts pulled on the membranes of beating cardiomyocytes and disturbed their electrical rhythm. Before this study, scientists were aware that myofibroblasts influenced the function of cardiomyocytes by depositing scar tissue, which produces regions of poor or no conductivity in healing cardiac tissue. But the “pulling” scenario described by Tung’s group indicates that myofibroblasts play a more active role than previously realized, Thompson said.

Biomedical engineering professor Leslie Tung collaborated with physics professor Daniel Reich to understand how heart scar tissue actively contributes to deadly arrhythmias. (Photo by Jay VanRensselaer)

In fact, images created using a voltage-sensitive dye showed that the spread of electrical waves was greatly impaired in the cultures with the most non-beating cells. Electrical conduction improved significantly, however, when drugs were added that inhibited contraction or that blocked so called “mechano-sensitive” channels.

“This is a truly exciting discovery because it radically affects our way of thinking about how cardiac arrhythmias might arise,” Tung said.

Tung and Thompson wanted to find out how strong the forces exerted by the myofibroblasts were and whether they changed when certain drugs were added. So they turned for answers to Daniel Reich, professor and chair of the Henry A. Rowland Department of Physics and Astronomy in the Krieger School of Arts and Sciences, and his pre-doctoral student Craig Copeland.

To measure the strength of the contractile forces of the myofibroblasts, the team used a device made up of a platform comprising an array of flexible “microposts.” The array resembled a carpet with widely spaced fibers upon which single cells can grow. As the cells responded to their environment, they pulled on the posts. How much the posts bent provided data about the direction and strength of forces exerted. Single layers of myofibroblasts were grown on the micropost device and tested in the presence of the same compounds Thompson used in her conductivity experiments.

“Imagine gripping a basketball with one hand, palm facing downward,” Copeland said. “The forces you apply to the ball with your fingertips to keep it suspended are similar to the forces cells exert on their environment. If you were to place your hand on a bed of rubber nails and apply the same gripping force with your fingertips as you did with the basketball, the nails would bend and their tips be deflected. This is exactly what happens with cells cultured on the post arrays.”

Thompson also explained that scientists previously thought that non-beating cells affected the beating cells simply through openings called “gap junctions,” where the two cells came into physical contact. The greater electrical charge of the myofibroblasts would flow passively downhill through the gap junctions toward the cardiomyocytes and disrupt their rhythms.

Photo by Jay VanRensselaer

The group’s new hypothesis suggests another type of membrane channel opened by physical force—the mechano-sensitive channels—may be more important in regulating electrical activity of the cardiomyocytes than mere junctions connecting membranes.

The results of both the conductivity and the micropost experiments fully support this new hypothesis, the team said. Although they acknowledge that both the passive gap channels and the active pulling forces can explain how myofibroblasts affect the electrical activity of cardiomyocytes, the researchers believe the pulling forces could be more relevant to the development of deadly arrhythmias.

“We are not ruling out the current theory,” Thompson said. “But we are saying there is something else we should be looking at, and we think the pulling forces are a major component. This could provide another lane of therapeutic investigation, especially if drugs could be targeted specifically to the contraction of the myofibroblasts.”

The next step in the project will be to combine the micropost device with electrical experiments on cultures containing cardiomyocyte and myofibroblast cell pairs.

“Although technically quite challenging, it will allow us to unravel how pulling forces applied by the myofibroblast to the cardiomyocyte affects the cardiomyocyte’s electrical activity,” said Tung.

Both Tung and Reich are affiliated faculty members of Johns Hopkins Institute for NanoBioTechnology. Thompson and Copeland are INBT fellows in the institute’s Integrative Graduated Education and Research Traineeship (IGERT), funded by the National Science Foundation (NSF). The National Institutes of Health, American Heart Association and the NSF IGERT funded their work. Findings were published in the May 17, 2011 issue of the journal Circulation.

Story by Mary Spiro

Photos by Jay VanRenesselaer/Homewood Photography

Festival draws half a million fans of science and engineering

Charli Dvoracek shows off some nanoparticles at the USA Science & Engineering Festival. (Photo: Mary Spiro)

The scene was a sea of white tents spread across the National Mall in Washington, DC and science and engineering were the order of the day. That’s what greeted visitors to the booth hosted by Johns Hopkins Institute for NanoBioTechnology at the first USA Science & Engineering Festival Expo, held October 23-24.

An estimated 500,000 people attended the two-day event, which featured 550 participating organizations and 1,500 hands-on activities. Those who stopped by INBT’s “Nano-Magic” booth learned about how atoms, molecules and materials have ways of building structures all by themselves.

Twelve graduate students affiliated with INBT training programs and a handful of friends of the Institute volunteered to help visitors understand the science. In addition, several of the research and news videos created by INBT’s Animation Studio were on display throughout the day.

An estimated 500 to 600 people came to the INBT booth and spent from 5 to 20 minutes discussing nanotechnology, Johns Hopkins research, and INBT’s training programs. This first-ever event was a major outreach opportunity for INBT and one of the first times the Institute has had a public display of this kind.

Tania Chan working with youngsters at the USASEF. (Photo: Mary Spiro)“Outreach serves an important purpose,” said Denis Wirtz, INBT’s associate director and professor of chemical and biomolecular engineering who came out Saturday to assist with the demonstration. “It showcases the interdisciplinary nature of INBT’s work to a broad audience. But it also gives the students an opportunity to explain their research in an accessible way. These outreach activities are a requirement of their training program grants, but this skill will also help them in their future careers when explaining their work to funding sources.”

USA Science and Engineering Festival organizers have not announced whether or not they will host another event like this one next year. INBT leaders indicate, however, that they will be interested in participating in this or similar events in the future.

Six exhibitors from Johns Hopkins presented at the USA Science and Engineering Festival. Along with INBT, they included representatives from the Institute for Data Intensive Engineering and Science and the department of Chemical and Biomolecular Engineering from the Whiting School of Engineering and the undergraduate program in neuroscience, the department of Physics and Astronomy, and the Institute for Biophysical Research from the Krieger School of Arts and Sciences.

USA Science and Engineering Festival Website

Johns Hopkins Institute for NanoBioTechnology

INBT welcomes 16 summer nanobio research interns

For 10 weeks this summer, 16 students from universities across the country will join the highly competitive Johns Hopkins Institute for Nanobiotechnology (INBT) Research Experience for Undergraduates (REU). The internship is funded by the National Science Foundation (NSF) and is supported and administered by INBT.

This is the third year of INBT’s REU program, and this group represents the institute’s largest group. Students are being mentored by faculty, graduate students and postdoctoral fellows in INBT affiliated laboratories across Hopkins. At the end of the 10-week research program, they will present their findings at a university-wide collaborative research poster session held with other summer interns from across several divisions.

In November 2009, NSF reported that over the last decade 10 times more white students will have earned doctoral degrees in science and engineering disciplines than minority students. Acknowledging this fact yet resolving not to accept it as status quo, INBT has employed aggressive measures to increase the number of individuals from underrepresented groups who apply to its educational programs.

“The nanobiotechnology REU has been one of the most successful and popular programs for INBT,” says Ashanti Edwards, senior education program coordinator for the institute. “The program has consistently attracted the best and the brightest students interested in research from top universities across the nation. The REU program was launched as a conduit to attract highly talented and motivated research students to pursue academic careers in research, particularly women and minority scholars. The program is highly competitive. For summer 2010, the number of applicants for the 10 slots in the program rose to nearly 500, twice what it had been the year before.”

Johns Hopkins Institute for NanoBioTechnology Summer REU Students. (Photos by Mary Spiro)

INBT’s summer 2010 REU students include pictured from top to bottom, from left to right:

Top row

Joshua Austin, computer science and math major from UMBC, is working with Jeff Gray, associate professor of chemical and biomolecular engineering, Whiting School of Engineering.

Mary Bedard, biochemistry and Spanish major from Elon University, is working with J.D. Tovar, assistant professor of chemistry, Krieger School of Arts and Sciences.

Kameron Black, neuroscience major from the University of California, Riverside, is working in the lab of Ted Dawson, professor of neuroscience, School of Medicine

Obafemi Ifelowo, who majors in molecular biology, biochemistry and bioinformatics at Towson University, is working with Jordan Green, assistant professor of biomedical engineering, School of Medicine.

Second row

Alfred Irungu, mechanical engineering major at UMBC, is working with German Drazer, assistant professor of chemical and biomolecular engineering, Whiting School of Engineering.

Ceslee Montgomery, human biology major from Stanford University, is working in the lab of Doug Robinson, associate professor of cell biology, School of Medicine.

Makeda Moore, biology major from Alabama A & M University, is working with Sharon Gerecht, assistant professor of chemical and biomolecular Engineering, Whiting School of Engineering.

Christopher Ojeda, biomedical engineering major from New Jersey Institute of Technology, is working in the lab of Michael Yu, assistant professor of Materials Science and Engineering, Whiting School of Engineering.

Third row

Katrin Passlack, mechanical engineering and kinesiology major at the University of Oklahoma, is working with Jeff Wang, associate professor of mechanical engineering, Whiting School of Engineering.

Roberto Rivera, chemical engineering major from the University of Puerto Rico, Mayaguez, is working in the lab of Nina Markovic, associate professor of physics, Krieger School of Arts and Sciences.

D. Kyle Robinson, bioengineering major from Oregon State University, is working in the lab of Denis Wirtz, professor of chemical and biomolecular engineering, Whiting School of Engineering. In addition, Kyle is the first REU intern for Johns Hopkins new Engineering in Oncology Center, of which Wirtz is director.

Russell Salamo, biology major from the University of Arkansas, is working with Kalina Hristova, associate professor of materials science and engineering, Whiting School of Engineering.

Bottom row

Quinton Smith, major in chemical engineering with a bioengineering concentration from the University of New Mexico, is working with Sharon Gerecht, assistant professor of chemical and biomolecular engineering, Whiting School of Engineering.

David To, chemistry major from Wittenberg University, is working with assistant professor Hai-Quan Mao in the department of materials science and engineering, Whiting School of Engineering.

Alan Winter, biology systems engineering major from Kansas State University, is working with Professor Peter Searson in the department of materials science and engineering, Whiting School of Engineering. Searson is the director of INBT.

Mary Zuniga, biology major a Northern Arizona University, is working in the lab of David Gracias, associate professor of chemical and biomolecular engineering, Whiting School of Engineering.

Related Links:

Johns Hopkins NanoBio Research Experience for Undergraduates