Natural Killer (NK) cells and their properties

Natural Killer (NK) Cells and Their immunological memory

The following article is a summarized version of the little eBook on NK cells – “Natural Killer (NK) Cells and Their immunological memory“. You can also find some illustrations (images) in the eBook.

Natural Killer (NK) cells are lymphocytes that belong to the innate immunity. They have an ability to kill the cells such as cancer cells and viruses. They are present in different parts of the body such as liver, lung, spleen, kidney, and other lymphoid tissues. Recent studies have shown that they have an ability to remember past events of infection, thereby responding to the new infections accordingly.

Several receptors, cytokines, and certain other pathways are found to be involved in the development of memory NK cells.

Receptors may include

  • Natural killer group 2, member D (NKG2D), which are also found on T cells,
  • CXC-chemokine receptor 6 (CXCR6),
  • LY49H (also known as KLRA8) along with cognate viral ligand m157, and
  • CD94:NKG2C receptors, which are found to be involved in remembering cytomegalovirus infection in humans.
Presence of NKG2D receptors in the body and their activity
Presence of NKG2D receptors in the body and their activity

Cytokines and other pathways may include

  • IL‑12,
  • IL-15,
  • IL-18,
  • IFNγ and
  • type I IFNs

Memory NK cells in the body may vary from each other as, for example, memory NK cells developing as a result of human cytomegalovirus infection are different from cytokine induced memory NK cells, i.e. they have/express different kinds of receptors and/or cytokines.

It has also been found that memory NK cells in different parts of the body are different from each other as, for example, memory NK cells in the liver could be different from memory NK cells in the lungs. However, studies on this aspect of memory NK cells could help in further understanding of memory NK cells.

Memory NK cells are also found to work along with T cells, i.e. they may support each other during different infections. (For further understanding see the eBook.)

Memory NK cells could help in the development of new kinds of therapeutic strategies against viral and bacterial infections, and cancer. (For some strategies check the eBook.)

Source:

Natural Killer (NK) Cells and Their immunological memory (Kindle Edition)

Usman Zafar Paracha

Usman Zafar Paracha is Assistant Professor, Pharmaceutics, in Hajvery University, Lahore, Pakistan.