In Review

Proponents of charter schools have long argued that the schools offer a valuable alternative to their public counterparts, particularly in troubled districts with large numbers of poorly performing schools. In a study published in American Economic Review , John Singleton, an assistant professor of economics, presents evidence of a major factor hindering charter schools in achieving that promise.

Looking at Florida schools as a case study, Singleton concluded that a typical formula for funding charter schools—a universal per-pupil cost estimate that makes no distinction based on students’ needs—has provided a strong incentive to locate charter schools in affluent areas.

“Many charter schools are moving into neighborhoods where they’re not serving what we consider to be the social purpose of charter schools,” says Singleton. “My hypothesis is that many students going to those schools are simply ones who would otherwise go to private schools.”

To encourage the establishment of charter schools in underserved areas, Singleton urges the adoption of funding programs that account for the likely operational costs of the schools.

—Peter Iglinski ’17 (MA)

How do immune cells find their targets?

When immune cells get recruited to infections, tumors, or other sites of inflammation, they exit the blood stream and begin searching for the damage.

But how do they effectively traverse the body’s tissue and home in on their targets? A study led by Deborah Fowell, Dean’s Professor in the Department of Microbiology and Immunology, suggests that the T cells have distinct navigation systems that help them pinpoint their targets.

Fowell’s research team, based in the David H. Smith Center for Vaccine Biology and Immunology in the Department of Microbiology and Immunology, made the discovery using a technology that allows researchers to look directly into the skin and observe the behavior of immune cells “live.”

The team’s findings were published in the journal Immunity.

“We thought that locating the infection foci was a passive event for immune cells; that they used the tissue as a scaffold to weave their way through this complex matrix to get to their target,” says Fowell. “We discovered that they are pre-programmed to respond to certain cues within the tissue microenvironment that help them find their targets more efficiently.”

The research is a result of a five-year National Institutes of Health grant awarded in 2014. In October, the team won an additional five-year NIH grant that will allow it to take the next step: exploring strategies to better fight infections like the flu and beat back overactive immune responses in disorders like rheumatoid arthritis and lupus.

The team hopes that the discovery will lead to therapies that manipulate the immune system to respond only to targeted diseases or tissues, rather than globally suppress the immune system.

—Emily Boynton

How machine learning helps measure climate change

Tom Weber, an assistant professor of earth and environmental sciences, led a team that used data science to fill a long-standing gap in methane cycle research. Their findings will help climate scientists better assess the extent of human impact on greenhouse gas emissions.

Every three years, an international group of climate scientists updates what is known as the methane budget. Methane is collecting in the atmosphere as a result of both natural processes and human activities. The ocean is known to be a major source of natural emissions, “but we don’t necessarily know how much,” says Weber. Because the ocean is so vast, only small portions of it have been sampled for methane.

To overcome the limitation, Weber worked with Nicola Wiseman ’18, now a graduate student at the University of California, Irvine, to compile available methane data from the ocean and feed it into machine-learning models—computer algorithms designed for pattern recognition. As reported in the journal Nature Communications, the models were able to recognize systematic patterns in the data, allowing researchers to predict what emissions are likely to be, even in regions where no direct observations have been made.

The data will be incorporated in the next methane budget, to be released later this year. The result will be the most accurate budget yet. That’s significant in the quest to understand—and rein in—climate change.

“The methane budget helps us place human methane emissions in context and provides a baseline against which to assess future changes,” Weber says.

—Lindsey Valich

Frontiers in the treatment of a deadly cancer

Pancreatic cancer is a notorious killer. It is often aggressive and usually discovered late. Moreover, pancreatic tumors are particularly hard to treat because they are surrounded by a toxic stew of proteins and other tissues that protect the cancer cells from the immune system.

Researchers at the Wilmot Cancer Institute went looking for a treatment combination that could do two things at once: activate T cells to attack the cancer and convert the immune-suppressing cells into fighters.

In a study in the journal Cell Reports, the team—led by principal investigator Scott Gerber, an assistant professor in the Department of Surgery, and Bradley Mills, a postdoctoral fellow in Gerber’s lab—describe a type of radiation therapy combined with immunotherapy that not only cured pancreatic cancer in mice but also appeared to reprogram the immune system to create an “immune memory” much like a standard vaccine does.

As a result, the treatment also destroyed cancer cells that had spread to the liver, a common site for metastatic disease.

With additional funding awarded in July from the National Cancer Institute, the team will continue the research and move the findings into clinical trials.

—Leslie Orr