“The strength of this biogel is that it is compatible with anti-cancer immune cells. It is used to encapsulate these cells and eventually administer them using a syringe or catheter into the tumour or directly beside it. Instead of injecting these cells or anti-cancer drugs throughout the entire body via the bloodstream, we can treat the cancer locally. We hope that this targeted approach will improve current immunotherapies.” Réjean Lapointe, senior author of the study.
Current immunotherapy techniques that use the patient’s own T cells to fight off cancer has been well established. But because the body’s natural T cells are insufficient in number and strength to fight off cancer fully, scientists devised a method give the T cells more firepower. Known as adoptive cell therapy (ACT), scientists collect the patient’s own T cells, modify them to enhance tumor recognition, increase their numbers to billions, and then inject them back into the patient to finish the job.
While this technique has shown to be effective in small trials involving leukemia and lymphoma patients, there are several limitations: extraordinarily high cell count requirement, and toxicity due to high doses of interleukin-2, a hormone added to maximize effectiveness.
The biogel breaks through these limitations as it requires millions of T cells instead of billions, and in the process, significantly reduces the toxicity by the interleukin-2 hormone. Developed by Sophie Lerouge, the biogel is made from biodegradable material taken from the shells of crustaceans. The biogel is liquid at room temperature and becomes a cohesive gel at 37 degrees Celsius, the human body temperature. Additionally, the biogel is non-toxic to the body and “provided excellent survival and growth of the encapsulated cells,” said Lerouge. Once inside the body, the gel serves as a “cellular reservoir” deploying and renewing the cancer-killing T cells.
"The T lymphocytes in the gel are functional and can grow for two to three weeks, be released from the gel, and kill the cancerous cells," explained Réjean Lapointe, senior author.
Early in vitro experiments testing the gel on melanoma and kidney cancer models have so far been reported as successful. The researchers plan to test the biogel in animal models, and if effective, will move towards human trials. If the biogel performs well, the tool will likely be adapted to treat many types of cancer in the next few years.
Sources: BioMaterials, Science Daily