Presentation (1).pptx to kill or not to kill nk cells

To kill or not to kill the natural killer cells

1. To Kill or Not To Kill: Functions And Importance Of NK (Natural Killer) Cells Deniz demir (2301015263) Faculty of medicine

2. Contents: What are NK cells? NK cell functions Inhibition and activation Importance of NK cells in body References

3. What are natural killer cells? Natural killer cells are white blood cells that destroy infected and diseased cells, like cancer cells. They’re also a type of lymphocyte, like B-cells and T-cells. These cells try to prevent the viruses and cancer cells from spreading by destroying them in early stages.

4. NK cells are called “natural” killers because they can destroy potential threats without prior exposure to a particular pathogen. Other lymphocytes that destroy harmful cells, like cytotoxic T cells , need previous exposure to a pathogen before they can destroy it.

5. Function of NK cells Cytotoxicity Immunoregulation Activation & regulation

6. Cytotoxicity Nk cells ability to kill Cellular cytotoxicity, the ability to kill other cells, is an important effector mechanism of the immune system to fight against viral infections and cancer. Cytotoxic T cells and natural killer (NK) cells are the major mediators of this activity. NK cells can rapidly recognize and eliminate these threats through specialized receptor-mediated pathways.

7. How do NK cells work in immune system? NK cells play a crucial role in regulating the immune system by interacting with other immune cells like T cells , helping to maintain a balanced and coordinated immune response. The surface of an NK cell contains multiple receptors that work together to either activate or inhibit an NK cell from killing a target.

8. Natural killer (NK) cells avoid attacking healthy cells by recognizing markers that show they belong in the body. The most common marker is MHC-1. When MHC-1 on a target cell binds to an NK cell's inhibitory receptor, it turns off the NK cell's killing function. This means the NK cell leaves the healthy cell alone and moves on to check other cells, ensuring only infected or dangerous cells are targeted. Inhibition

9. Nk cells get activated to kill and destroy cells that don't recognize as belonging to the body, including: Cancer cells, which release chemical signals causing NK cells to attack. Cells which don’t express MHC-1 or has it less than normal, will get destroyed. Sometimes infection or virus may cause downgrade of a healthy cell’s expression of MHC-1. Activated NK cells release cytokines that will tell other white blood cells to help saving body Activation

10. Conclusion Natural Killer (NK) cells play a crucial role in the body's immune response, providing protection against various diseases and maintaining overall health. Their cytotoxicity and immunoregulatory functions make them a vital component of the immune system, with far-reaching implications in cancer, infectious diseases, and beyond.

11. Thank you for listening

12. References https://www.nature.com/articles/s12276-020-00505-7 https:// www.ncbi.nlm.nih.gov / pmc /articles/PMC5357635/#:~:text=The% 20immunoregulatory %20function%20of%20NK%20cells%20in%20infection%20and% 20inflammatory,chronic %20inflammatory%20diseases%20(88) . https:// my.clevelandclinic.org /health/body/24898-natural-killer-cells https://www.immunology.org/public-information/bitesized-immunology/cells/natural-killer-cells