According to a study published in the journal Science, cancer treatment has transformed thanks to immunotherapy. The five-year survival rate for advanced melanoma, the deadliest type of skin cancer, has climbed from less than 10% to more than 50% since the development of immunotherapy in 2011.

In the study, the researchers found that an immune cell known as CD5+ dendritic cells is the difference between people who respond and do not respond to immunotherapy. They discovered that people lacking the CD5 protein on their dendritic cells did not respond well to immunotherapy and that patients with various malignancies, including melanoma, lived longer if their tumours had more CD5+ dendritic cells.

The researchers explained that the immune system protects the body from cancer by turning on T cells, which are immune cells that can identify and eliminate tumour cells. Immune checkpoint blockade therapy prevents tumour cells from manipulating the immune system, allowing T cells to detect and eliminate cancer.

The results of the study showed that determining which patients are most likely to benefit from immunotherapy may be based on the number of CD5+ dendritic cells present inside tumors. They also found that the immunological protein IL-6 boosts the number of CD5+ dendritic cells as part of this investigation. Additionally, they suggested that raising the quantity or activity of such dendritic cells may increase the number of patients who can benefit from immunotherapy. 

(Source: https://theprint.in/health/cancer-patients-who-do-not-react-to-immunotherapy-lack-crucial-immune-cells-study-2/1378751/ )