Trick or treat: "Tricking" immune system may be key to fighting cancer and infectious disease

Sombit Mishra

3D image of cancer cells under microscopeHarvard bioengineers have developed an injectable 3D scaffold capable of boosting natural immune response to tumor cells.  The approach could be a breakthrough in the fight against cancer and infectious diseases.

Study Highlights:  

  • "The goal of cancer vaccines is to provoke the immune system to recognize cancer cells as foreign and attack them."
  • Cancer cells are notoriously difficult for the human immune system to distinguish from normal healthy cells.  As a result, dendritic cells of the immune system often "overlook" cancer cells, making it harder to fight the spread of disease.
  • Traditionally, dendritic cell therapy has centered upon removing dendritic cells from the bloodstream, incubating the cells with patient-specific tumor antigens, and injecting the combined "re-programmed" cells back into the bloodstream.  This approach has had short-lived efficacy in targeting and fighting cancer cells throughout the body, in part because manipulating dendritic cells artificially is very difficult.  In addition, removing dendritic cells from the body is very expensive to administer.
  • Solution: The Harvard team tested a biodegradable 3D scaffold that harnesses tumor antigens and attracts millions of dendritic cells when injected under the skin.   These dendritic cells then interact with the tumor antigens in the scaffold, which thereby allows the body to "re-program" the dendritic cells naturally.  Once the dendritic cells are re-programmed, they are carried to the lymph nodes, where the rest of the immune system's cells can readily recognize and attack diseased cells.
  • In mice, the 3D scaffold achieved a 90% survival rate in mice that would have otherwise died in 25 days.

The burden of proof for such novel immunotherapies will ultimately depend on running longitudinal studies to evaluate spread of disease cells and survival rate.  But this is a very promising start and another example of how injectable biomaterials can be used to improve outcomes while reducing the cost of care.