To use all functions of this page, please activate cookies in your browser.
my.bionity.com
With an accout for my.bionity.com you can always see everything at a glance – and you can configure your own website and individual newsletter.
- My watch list
- My saved searches
- My saved topics
- My newsletter
White blood cell
White blood cells, or leukocytes, are cells of the immune system defending the body against both infectious disease and foreign materials. Several different and diverse types of leukocytes exist, but they are all produced and derived from a multipotent cell in the bone marrow known as a hematopoietic stem cell. Leukocytes are found throughout the body, including the blood and lymphatic system. The number of leukocytes in the blood is often an indicator of disease. There are normally between 4×109 and 11×109 white blood cells in a liter of blood, making up approximately 1% of blood in a healthy adult.[1] In conditions such as leukemia the number of leukocytes is higher than normal, and in leukopenia this number is much lower. The physical properties of leukocytes, such as volume, conductivity, and granularity, may change due to activation, the presence of immature cells, or the presence of malignant leukocytes in leukemia. Additional recommended knowledge
EtymologyThe name "White Blood Cell" derives from the fact that after centrifugation of a blood sample, the white cells are found in the Buffy coat, a thin layer of nucleated cells between the sedimented red blood cells and the blood plasma, which is typically white in color. The scientific term leucocyte directly reflects this description, derived from Greek leukos - white, and kytos - cell. Blood plasma may sometimes be green if there are large amounts of neutrophils in the sample, due to the heme-containing enzyme myeloperoxidase that they produce. TypesThere are several different types of white blood cells. One primary technique to classify them is to look for the presence of granules, which allows the differentiation of cells into the categories granulocytes and agranulocytes:
The functions and morphology of these cells are as follows:[1]
Medications causing leukopeniaSome medications can have an impact on the number and function of white blood cells. Leukopenia is the reduction in the number of white blood cells, which may affect the overall white cell count or one of the specific populations of white blood cells. For example, if the number of neutrophils is low, the condition is known as neutropenia. Likewise, low lymphocyte levels are termed lymphopenia. Medications which can cause leukopenia include clozapine, an antipsychotic medication with a rare adverse effect leading to the total absence of all granulocytes (neutrophils, basophils, eosinophils). Other medications include immunosuppressive drugs, such as sirolimus, mycophenolate mofetil, tacrolimus, and cyclosporine. Interferons used to treat multiple sclerosis, like Rebif, Avonex, and Betaseron, can also cause leukopenia. Fixed leukocytesSome leukocytes migrate into the tissues of the body to take up a permanent residence at that location rather than remaining in the blood. Often these cells have specific names depending upon which tissue they settle in, such as fixed macrophages in the liver which become known as Kupffer cells. These cells still serve a role in the immune system. Additional image(s)See also
References
Categories: Leukocytes | Hematology | Immunology | Immune system |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "White_blood_cell". A list of authors is available in Wikipedia. |
- AyoxxA Biosystems Closes Series A Financing Round - 2.6 million Euro financing will accelerate development of cutting-edge technology for protein analysis
- Glucagon
- Alagille_syndrome
- How cells rewrite their fate - The study could be the starting point for new methods to alter the molecular mechanisms of cancer development
- 3D-printed pills with desired drug release – a step upwards in medication - Funny looking pills are not a design gimmick, they can release medication in a desired time regime!