T cells may be able to reach their full potential in the fight against cancer with a little nudge. In 2010, scientists first observed CD4+ T cells transitioning from a regulatory role to a cytotoxic role, directly targeting and killing cancer cells as a result of immunotherapy. After this observation, the same team sought to identify the key mechanisms behind this transition. What molecular and cellular interactions are necessary to “nudge” CD4+ T cells in a more cytotoxic direction when survival against cancer is on the line?
T cells like CD4+ cells are included as ingredients in immunotherapy protocols because of their role in the immune response to threats against the body, including cancer and pathogens. Immunotherapy is an approach to cancer treatment that relies on boosting the body’s natural mechanisms for thwarting cancer, including optimizing the activity of immune system components like T cells. To reach their full potential, some T cells first need be equipped to recognize cells as cancerous when necessary.
A new study conducted in mice identified T cell growth factor interleukin (IL)-2 and transcription factor Blimp-1 as factors responsible for altering CD4+ T cells’ functional identity, triggering the change from regulatory to cytotoxic in the context of cancer.
Past research of IL-2 associates this growth factor with working alongside regulatory T cells to maintain self-tolerance, the immune practice of preventing immune cells from attacking the body’s own cells during the immune response. Blimp-1, also know as “B lymphocyte-induced maturation protein-1,” is linked to the “development and function of antibody-producing B cells,” an important part of the adaptive immune response.
With this information, researchers can optimize the way in which they recruit CD4+ T cells in immunotherapy approaches to treat cancer. Upon translating the results of the current study to cases of human immune interactions, researchers can develop novel custom cell therapies specifically targeting IL-2 and Blimp-1 in different contexts of cancer. Results from the present study have the potential to greatly improve the way scientists equip T cells to recognize cancerous cells for application of immunotherapy.