Cancer vaccines are on the horizon, set to become a vital component of the inevitable but multifaceted cure for cancer.
Our bodies are teeming with bacteria, both inside and out, many of which provide health benefits. But why does the immune system—which is designed to recognize and attack foreign invaders—tolerate these friendly-yet-foreign commensal bacteria? The simplest explanation might be that these bacteria do not elicit an immune response. However, this is not the case. The immune system is in fact mobilized against these foreign microorganisms but does not eliminate them as it would pathogenic (disease-causing) bacteria. But why?
Here, researchers from Stanford sought to understand this tolerance by attempting to disrupt it. They engineered commensal skin bacteria to produce a protein they would not naturally express—a protein typically produced by human tumor cells—and then studied the resulting immune response. Surprisingly, when these engineered bacteria were applied to mouse skin, they triggered a robust immune response. This immune response acted as a potent tumor vaccine, preventing tumor formation and even eliminating pre-existing tumors.
While their original aim was to investigate basic immune tolerance, the researchers unexpectedly developed a novel approach to creating cancer vaccines. This underscores the importance of keeping an open mind in research, as some of the most significant discoveries often arise from the unexpected.
