With Hartwell funds, Teplensky aims for a more potent shot against Streptococcus pneumoniae
By Patrick L. Kennedy
While it doesn’t garner the headlines of other infectious respiratory diseases, pneumonia routinely sends kids to the hospital, especially children with compromised immune systems. And pneumonia is just one of the life-threatening diseases (along with meningitis and others) caused by the bacteria Streptococcus pneumoniae (Spn).
Vaccines exist that target Spn, but they struggle to protect against all the variants of the bacteria that emerge, and they can require a four-vaccine series for substantial potency. “There’s a huge amount of room for improvement,” says Assistant Professor Michelle Teplensky (BME, MSE).
With an award from the Hartwell Foundation, Teplensky and colleagues are working on a new way to design a more powerful, versatile, and enduring Spn vaccine, protecting vulnerable children with just one shot.
A panoply of parameters
Every vaccine consists of two elements, Teplensky explains: a stimulator, which turns on an immune response; and a target—for example, a shred of dead virus or bacteria—which tells the immune system what to go after.
Both of those elements are subject to untold numbers of variables—their precise size and shape, the kind of target, how they are released, and more. Those parameters affect a vaccine’s reception in the body, Teplensky says, which might explain the disappointing success rate of various current vaccines: “No one takes all of these factors into consideration.”
But if the stimulator and target cues are highly variable, Teplensky believes—and her recent work shows—that also means they’re tunable.
Broader target, stronger shot
“What this project is all about is changing how we deliver those cues to an immune cell so that we can maximize that vaccine’s potency,” Teplensky says.
Using chemistry and nanotechnology, Teplensky and colleagues are creating synthetic DNA with novel shapes and structures. “We can make it 100 nanometers large or five nanometers large,” she says. “We can change all aspects of its appearance and structure.” Ultimately, the team aims to deliver a target that trains the immune system to react to a broader range of real Spn bacteria down the road. This idea of a “pan-Spn” response is a more sustainable long-term strategy to cover a broad spectrum of known and unknown serotypes (variants).
That one versatile vaccine will mean fewer trips to the clinic for harried parents of babies and toddlers. “The current Spn regimen is up to something like four shots starting at an age of two months,” says Teplensky. “It becomes a little arduous. The goal of this work is to create a more potent and broad response with a single injection.”
Combining expertise to find a solution
Teplensky’s collaborators include Professor of Medicine Joseph Mizgerd of the BU Chobanian & Avedisian School of Medicine and Director of the BU Pulmonary Center, as well as a clinical partner, Dr. Richard Malley, at Boston Children’s Hospital. “What my lab does is very much at the intersection of so many fields, including immunology and biomedical engineering as well as chemistry and nanotechnology, and this enables us to work with those at the forefronts of the disease biology and clinical interaction,” she says.
“It’s part of the values of our lab to think about the end user,” adds Teplensky. In this case, that means the very young—who are more inclined to get sick under the best of circumstances—and in particular immuno-compromised kids, who need this help the most. “I don’t think it gets more meaningful than helping children who are vulnerable.”