Howdo white blood cells protect the body from disease?Functionof white blood cellsMatthewMullett Biology111Mrs.StandringDecember.18, 2017 The body uses the immune system to defend its self frominfections and viruses.
The immune system has a series of methods used toprotect your body. The most important one are your white blood cells or alsoknown as leukocytes. These cells defend the body against infection and diseaseby ingesting foreign materials and debris, by destroying infectious agents andcancer cells, or by producing antibodies (Britannica 1). White blood cells arefound in lots of places throughout the body. Most are found outside ofcirculation within tissue where they fight infections; the few found in theblood stream are in transit from one site to another (Britannica 3). The white blood cells are grouped intothree major classes: Lymphocytes, Granulocytes, and Monocytes – each with adifferent function (Britannica 3). As every thing else in the world, the white bloodcells can develop conditions that can have a fatal effect on a person.
Lymphocytes are really what is associated with whiteblood cells. The fact that they encounter a foreign invader or infection anddestroy it. Lymphocytes are responsible for the specific recognition of foreignagents and their subsequent removal from the host (Britannica 4).
This type ofcell is then subdivided into T cells and B cells. The B cells or B lymphocytesare what produce antibodies (Yamini 2). B cells are like the body’s militaryintelligence that seek out targets and send defense to destroy them (Yamini 2).Then there are the T cells that destroy antigens that have been tagged byantibodies or cells that have been infected or somehow changed (Yamini 3).
Tcells are like the soldiers, they destroying the invaders that the intelligencesystem (B cells) has identified (Yamini 2). Another name for T cells areactually “Killer cells”. About 25 to 35 percent of white blood cells arelymphocytes in a healthy person (Britannica 4). Granulocytes are the most numerous of the white bloodcells that rid the body of large pathogenic organisms such as protozoans orhelminthes and are also key mediators of allergy and other forms ofinflammation (Britannica 4). Granulocytes are subdivided into three categories:Neutrophils, Eosinophils, and Basophils (Britannica 5).
Neutrophils are the firstcell types to arrive at an infection where they engulf and destroy theinfectious micro organisms through a process called phagocytosis (Britannica 5).Phagocytosis is when cells chew up the invading organisms (Yamini 2). Althoughafter a neutrophil engulfs any foreign particles they self-destruct (Dority 1).
About 50 to 80 percent of all white blood cells are neutrophils (Britannica 5). Basophils have granules that contain anumber of chemicals, including histamine that is important in inducing allergicinflammatory responses (Britannica 5) and heparin (Dority 2). Well what do thesetwo chemicals do exactly? Heparin is an anti-coagulant, meaning it preventsblood cells from clotting too quickly (Dority 2). Histamine is a vasodilatorthat is commonly released during allergic reactions to increase blood flow(Dority 2). Eosinophils are what destroy parasites and also help modulate inflammatoryresponses (Britannica 5). How eosinophils fight parasites are by releasingchemical mediators, peroxides, nucleases and lipases, by a process calleddegranulation with target pathogens (Dority 2). The third and final class are monocytes. Monocytes originatein the bone marrow and develop into large macrophages in the bloodstream(Dority 1).
These cells are scavengers and are therefore effective at directdestruction of pathogens and clean up cellular debris from sites of infection(Britannica 6). In other words, monocytes are what clean up the mess leftbehind from the destruction of a foreign invader. Between 4 and 8 percent ofwhite blood cells are monocytes in your blood (Britannica 6). White blood cells are also apart of another system knownas the lymphatic system. This system is made up of lymph nodes that work likefilters to remove any germs that could make you sick, in this case it’s a clearfluid called lymph that contains leukocytes (white blood cells) inside of it(article 2 pg.
1). All of these different classes and subdivisions of whiteblood cells aren’t because there are so many. Its because specific types ofcells are associated with different illnesses which reflect the specialfunction of that cell type in body defense (Britannica 6). This is seen in newbornswho have a high white blood cell count that gradually to the adult level duringchildhood (Britannica 6). This is a natural response as newborns are moresusceptible to getting an infection (Britannica 6).
How do white blood cells know then when it s time forthem to destroy a foreign invader? It was found that white blood cells make aprotein called HIF-1 that boost the production of antibacterial compounds whenoxygen levels begin to drop, or when the cell encounters a harmful bacterium(Coombs pg.1). “turning on the HIF-1 is like a white blood cell pulling outit’s sword as it enters infected tissue” (Coombs pg. 1).
Therefore, if theywere always making killer compounds it might destroy the good cells and wastegood energy (Coombs Pg.1). Some people have problems with their immune systemmeaning it may respond to non-dangerous materials in a potentially pathogenicway.
Allergies, an example of this is when the immune system overreacts andtreats something harmless like peanuts as though is was really dangerous to thebody (article 2 pg.2). Well what is it that causes this? Its certain medicalconditions such as lupus that cause the immune system to fight the good cellsand this can cause problems (Britannica Pg.2). The immune systemis a well regimented army working together to combat the dangerous foreigninvaders.
Its battalions consist of front line white cells in the form ofneutrophils, Special operations white cells in the form of basophils andfinally eosinophils. Together these types of cells are what make upgranulocytes cells that rid body of disease. While the lymphocytes are whatfind diseases or infections and tell the granulocytes to destroy them. Coombs, Amy. “KillerCells Get a Boost.” Science Now, 7/1/2005,p. 1. EBSCOhost, http://web.
a.ebscohost.com/ehost/detail/detail?vid=3=5cf78ace-c746-4c5d-a815-428e52293d77%40sessionmgr4007=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#AN=17564196=schDority, Jason. “White BloodCells & Their Functions.” LIVESTRONG.COM, Leaf Group, 14 Aug.2017, www.livestrong.
com/article/106131-white-blood-cells-functions/.”Immune System.” Edited byYamini Durani, KidsHealth, The Nemours Foundation, May 2015, kidshealth.org/en/parents/immune.html.
The Editors of EncyclopædiaBritannica. “White blood cell.” Encyclopædia Britannica Encyclopædia Britannica, inc., 16 Feb. 2017, www.britannica.com/science/white-blood cell.
“Your Immune System.” Editedby Yamini Durani, KidsHealth, The Nemours Foundation, May 2015, kidshealth.org/en/kids/immune.html.