What is responsible for our defense?

The main task of the immune system is to fight against malignant cells, which can form almost every day and divide uncontrollably, causing cancer. Several healer cells, each with their function, help the immune system to do this.

T-lymphocytes play a leading role in the fight against neoplasms. Thanks to the antigens they contain, they identify defective cells and destroy them.

NK (natural killer) are killer cells that help T-lymphocytes. They can identify and destroy cells hidden by T-lymphocytes.

Macrophages come in two types: M1 and M2. M1 are warriors — not only do they fight the malignant cells themselves, but they also attract T-lymphocytes to the dangerous area. M2 macrophages are healing cells — they synthesize growth molecules that promote healing and tissue regeneration. However, the downside to M2 is that it stimulates tumor growth once in the area of the neoplasm.

Dendritic cells or antigen-presenting cells (APC) are special cells of the immune system of bone marrow origin that have toll-like receptors on their surface. These absorb enemy antigens and transmit information about them to T-lymphocytes, which triggers anticancer activity.

Regulatory T lymphocytes (T suppressors) are responsible for the strength and duration of the immune response by regulating the activity of other T-cells and dendritic cells.

Lymphokines are synthesized by all types of lymphocytes. Lymphokines coordinate and regulate the functions of immune system cells, and promote the growth and development of lymphocytes, macrophages, and neutrophils.

Myeloid-dependent suppressor cells (MDSC) are derived from bone marrow stem cells, have strong immunosuppressive activity, and interact with other immune cell types including T-cells, dendritic cells, macrophages, and natural killer cells to regulate their functions.

Why hasn’t cancer been defeated yet?

As we can see, we do have built-in immunity that can fight against cancerous cells. However, immunity sometimes fails. First, the immune system is disrupted by aggressive external factors, which are exacerbated when we lead unhealthy lifestyles.

Second, malignant cells can camouflage well, so our defenders don't notice them. And cancer cells are capable of killing immune cells themselves, weakening a person's immune system. Because of all of this, immunoprotection is given special attention in cancer treatment.

14 January 2022