Necrotaxis

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Necrotaxis embodies a special type of chemotaxis when the chemoattractant molecules are released from necrotic or apoptotic cells. [1] [2] Investigations of necrotaxis proved that ability to sense substances released from dying cells is present in unicellular level (e.g. Paramecium) as well as in vertebrates (see interactions of leukocytes with corpse of dead cells). Composition of the substances inducing necrotaxis is rather complex, some of them are still obscure. However, depending on the chemical character of molecules released, necrotaxis can accumulate or repel cells, [3] which underlines the pathophysiological significance of the phenomenon. [4] Model experiments of necrotaxis deal with special way of killing the target cells. For this purpose laser irradiation is used frequently. Several mathematical models are also available to describe the special locomotor characteristics of this migratory response of cells. [5]

Haptotaxis Necrotaxis-en.png
Haptotaxis

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Spermatozoon Motile sperm cell

A spermatozoon is a motile sperm cell, or moving form of the haploid cell that is the male gamete. A spermatozoon joins an ovum to form a zygote.

Capillary Smallest type of blood vessel

A capillary is a small blood vessel from 5 to 10 micrometres (μm) in diameter, and having a wall one endothelial cell thick. They are the smallest blood vessels in the body: they convey blood between the arterioles and venules. These microvessels are the site of exchange of many substances with the interstitial fluid surrounding them. Substances which exit include water, oxygen, and glucose; substances which enter include water, carbon dioxide, uric acid, lactic acid, urea and creatinine. Lymph capillaries connect with larger lymph vessels to drain lymphatic fluid collected in the microcirculation.

Blood–brain barrier Semipermeable capillary border that allows selective passage of blood constituents into the brain

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Cytokine

Cytokines are a broad and loose category of small proteins important in cell signaling. Cytokines are peptides and cannot cross the lipid bilayer of cells to enter the cytoplasm. Cytokines have been shown to be involved in autocrine, paracrine and endocrine signaling as immunomodulating agents. Their definite distinction from hormones is still part of ongoing research.

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CMKLR1

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S1PR4

Sphingosine-1-phosphate receptor 4 also known as S1PR4 is a human gene which encodes a G protein-coupled receptor which binds the lipid signaling molecule sphingosine 1-phosphate (S1P). Hence this receptor is also known as S1P4.

Prostaglandin DP<sub>2</sub> receptor

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References

  1. Bessis, M. (1964). "Studies on cell agony and death: an attempt at classification.". In DeReuck, A.V.S.; Knight, J. (eds.). Ciba Foundation Symposium - Cellular Injury. London, Churchill. p. 313. ISBN   9780470722770.
  2. Debru C. (1993). "A particular form of chemotaxis: necrotaxis. An historical view". Blood Cells. 19 (1): 5–19. PMID   8400312.
  3. Ragot R. (1993). "Negative necrotaxis". Blood Cells. 19 (1): 81–8. PMID   8400315.
  4. Bessis M (1974). "Necrotaxis. Chemotaxis towards an injured cell". Antibiot. Chemother. 19: 369–81. doi:10.1159/000395442. PMID   4463832.
  5. Hu CL, Barnes FS (1970). "A Theory of Necrotaxis". Biophys. J. 10 (10): 958–69. Bibcode:1970BpJ....10..958H. doi:10.1016/S0006-3495(70)86345-7. PMC   1367972 . PMID   5496909.