Newly Developed Cryogel-Based Vaccine Combats Cancer

Vaccine primes immune cells to attack patient-specific tumor tissue.

Injectable cryogel-based whole-cell cancer vaccines may be the wave in treating cancer, researchers at the Dana-Farber Cancer Institute report.

Researchers have found the vaccine delivers patient-specific tumor cells together with immune-stimulating biomolecules to enhance the body’s attack against cancer. The approach differs from other cancer cell transplantation therapies in that the new cryogel vaccine’s properties are used to evoke the immune response in a far simpler and more economical way.

Existing therapies harvest tumor cells and then genetically engineer them to initiate immune responses once they are transplanted back into the patient’s body. Cryogels, which are comprised of cross-linked hydrophilic polymer chains that have the ability to hold up to 99% water, are created by freezing a solution of the polymer in the process of gelling.

When they reach room temperature once more, the substance turns into a highly interconnected pore-containing hydrogel, which is similar in composition to bodily soft tissues in term of their water content, structure, and mechanics. The team of researchers were able to adjust their shape, physical properties, and chemical composition allowing them to generate sponge-like, porous cryogels that can be infused with living cells, biological molecules, or drugs for a variety of potential treatments, including cancer immunotherapy.

“Instead of genetically engineering the cancer cells to influence the behavior of immune cells, we use immune-stimulating chemicals or biological molecules inserted alongside harvested cancer cells in the porous, sponge-like spaces of the cryogel vaccine,” said David Mooney, PhD, Wyss Core Faculty member.

The cryogels are extremely flexible and resilient, which allows them to be compressed to a fraction of its size so scientists can administer the vaccine through a surgical needle. Once injected, the cryogels reassume their original size and continue to work their magic throughout the body.

“After injection into the body, the cryogels can release their immune-enhancing factors in a highly controlled fashion to recruit specialized immune cells which then make contact and read unique signatures off the patient’s tumor cells, also contained in the cryogels,” said Sidi Bencherif, the study’s co-first author and a Research Associate in Mooney’s research group. “This has two consequences: immune cells become primed to mount a robust and destructive response against patient-specific tumor tissue and the immune tolerance developing within the tumor microenvironment is broken.”

In experiments on animals, researchers found that the vaccine was positively associated with tumor size reduction and could even prophylactically protect animals from tumor growth. The team of researchers is excited to start testing the vaccine and how it can be broadly used to treat a number of different cancer types.

“This new injectable form of this biomaterials-based cancer vaccine will help to expand the cancer immunotherapy arsenal, and it’s a great example of how engineering and materials science can be used to mimic the body’s own natural responses in a truly powerful way,” said Don Ingber, the Wyss Institute’s Founding Director.