US scientists revealed a new way to conquer cancer tumors that suppress antitumor immune cells in the immediate vicinity of the affected fabric. It turned out that large secretory cells (Clara cells) isolated anti-immunosuppressive factors that suppress tumor cells. This is reported in the article published in the journal Nature Cancer.
Researchers have identified a set of anti-emunsuppressive factors that can be secreted by Clara cells, lining the respiratory tract in the lungs. These factors inhibit potent immunosuppressive cells called myeloid suppressor cells (MDSC), which help tumors avoid an antitumor immune response.
Inhibition of MDSC led to an increase in the amount of antitumor T cells at a tumor site and significantly increased the effectiveness of immunotherapy with the help of immunoglobulin PD1. Using the mouse model of the non-cellochomic cancer of the lung, the most common shape of the lung cancer, scientists first found that this effect reaches a maximum at a moderate radiation dose, and the number of surviving mice has four times and reached 40 percent. Radiation causes major secretory cells to produce anti-immunosuppressive factors.
Researchers found that it is possible to replace the radiation with a cocktail of eight factors and get the same anti-immunosuppressive effect. Currently, scientists are going to determine which molecules are most important for inhibiting MDSC and improving the effectiveness of cancer treatment.