natural killer cells

Victoria Brown

Biol 454L Thursdays 11:30-2:30pm

In 1975 NK cells also known as “natural killer cells” were discovered by a man named Rolf Keossling and his team in Sweden. There are two different types of lymphocytes known as the B cells and T cells but, so are NK cells. Lymphocytes are white blood cells that is one of the body main immune cells. NK cells are the most aggressive and lymphocytes that have no immunological memory. They estimate about 5-10% of the circulating lymphocytes population. When It comes to tumors, cancer and unrecognized virial infected cells NK cells play a major role in rejecting and killing them in the system. Although NK cells ae in the same family and progenitor as B and T cells; NK cells have a different ability to attack and kill tumor cells.

Natural killer cells have the ability to attach and kill tumor cells without activating to an antigen and presenting cells, and that’s how the name “natural killer” is another name for NK cells. Nk cells are a innate effector lymphocytes that are divided into cytokines that produce CD56 “bright” and CD56 “dim”. They also protect against many various infection’s microbes’ diseases. NK cells are found in multiple areas such as in the bone marrow, uterus, spleen, lungs, lymphoid tissues, thymus etc. When NK cells are working, they look for early cancer cells, diseases and cells that are not noticed in the body before. NK cells are activated by either macrophage cytokines or interferons and can respond indirectly or directly. If its directly they respond by recognized bad virus cells and indirectly means they are working with the dendritic cells that express toll like receptors that responds to microbes from secrete cytokines.

When a virus enters the system, it will multiply and copy on to health cells. NK cells work by getting in contact with the target and aims its lethal Tucson’s that will produce a hole in the cell they are targeting in the cell membrane and will destroy the cancer cell membrane and cell. It will be deleted to its death and this process is called that is called apoptosis manners. Apoptosis manners simply kills in a selective manner that is designed to kill cells. After the NK cells have attached and killed the cell, they are able to unattached and attach on to different abnormal cells in the system. When NK cells have moved on to look for more abnormal cells the old cells that have been attacked and deleted sometimes takes up to 24 hours to establish and separate themselves from different organs and disappear for good.

Stepping into a public place where thousands of people of have been you can be exposing yourself to bad bacteria and viruses you can’t see. NK cells are used in are everyday life because, each time you go into a area where multiple people have been you are at risk of touching or breathing another person germs. When a cold enters a body, it is the NK cells job to go and kill before hurting and affecting other healthy blood cells in the body. Many normal healthy cells will express MHC 1 receptors; which are antigen that alerts the immune system to viral infected cells. They can be expressed on the surface of the cell are present by peptide fragments from proteins. When NK cells recognize an MHC 1 it will prevent it from killing the cell.

In 2019 there was a virus discovered called Coronavirus 2019 that turned into a dangerous a global pandemic. Coronavirus disease 2019 abbreviated as COVID-19 is a new virus-related contagion triggered by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; originally abbreviated as 2019-nCoV, a new beta coronavirus initially recognized during an outbreak of respiratory infection cases in Wuhan City, Hubei Province, China. After a few weeks, the illness became a pandemic with 353,334 confirmed demises and 5,593,631 cases reported as of May 28. The review of latest statistics highlights the disregulated immune reaction and its inflammatory element as the leading cause of mortality and morbidity, underscoring the necessity of an improved understanding of the early occurrence that form the infection host retort in COVID-19. In this case, it is valuable remembering that the constituents of the inborn immune structure act as main responder for the discovery and clearance of virus-related contagions. Inborn immune cells discharge proinflammatory cytokines which constrain virus-related reproduction, provoke the adaptive resistant reaction, and recruit additional resistant cells to the place of infection. The employment of an effectual immune reaction is a vital feature in the clearance and control of virally infested cells. Certainly, adaptive and innate immune reactions work together to guard the host against microbial infections. Assumed the diverse regulatory and antiviral functions of natural killer (NK) cells, they may perhaps be powerful and potent immune associates in the worldwide fight against COVID-19.


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