|WikiProject Molecular and Cellular Biology||(Rated Start-class, Mid-importance)|
|This article is/was the subject of a Wiki Education Foundation-supported course assignment. Further details are available on the course page. Student editor(s) Immcarle18 will be working on it.|
I made the changes seen in the opening paragraph because it is too exclusive. IgM would not be considered an opsonin by the old definition. However, I fear I have risked the original simplicity of the article. However, this is at least a place to start, because above all else, the page needs to be accurate. — Preceding unsigned comment added by Creightonian (talk • contribs) 22:41, 7 February 2011 (UTC)
Etymology note to add
opsonin from Greek word meaning "“to supply or prepare food”"; http://bioetymology.blogspot.com/2011/10/opsonin_2610.html Twbeals31 (talk) 00:09, 10 November 2011 (UTC)
Proposed bibliography for future edits
I will be making some edits to this page as part of an Immunology course at Carleton College. My proposed bibliography is below. It consists of three review papers, as well as two primary studies. Unfortunately, a lot of the information out there about opsonins is from primary sources. I am going to try and rely more heavily on the secondary sources, but I may find myself referencing the primary papers for small points.
1. DiLillo, D. J., and J. V. Ravetch. 2015. Fc-Receptor Interactions Regulate Both Cytotoxic and Immunomodulatory Therapeutic Antibody Effector Functions. Cancer Immunology Research 3:704-713.
2. Litvack, M. L., and N. Palaniyar. 2010. Review: Soluble innate immune pattern-recognition proteins for clearing dying cells and cellular components: implications on exacerbating or resolving inflammation. Innate Immun 16:191-200.
3. Roos, A., W. Xu, G. Castellano, A. J. Nauta, P. Garred, M. R. Daha, and C. van Kooten. 2004. Mini-review: A pivotal role for innate immunity in the clearance of apoptotic cells. Eur J Immunol 34:921-929.
4. Sarma, J. V., and P. A. Ward. 2011. The complement system. Cell Tissue Res 343:227-235.
5. Zhang, Y., A. D. Hoppe, and J. A. Swanson. 2010. Coordination of Fc receptor signaling regulates cellular commitment to phagocytosis. Proc Natl Acad Sci U S A 107:19332-19337.
Proposed new lead section
As part of my project, I am posting a draft of what I think the lead section should be. Again, feedback is appreciated. This includes some new information to the page, as well as moving a lot of information from the mechanism section into the lead. I do not believe the mechanism section merits being separate from the lead at the moment, however I could be convinced otherwise. I also have included a number of revisions to wording, as some of it was inaccurate or confusing.
An opsonin (from the Greek opsōneîn, to prepare for eating) is any molecule that enhances phagocytosis by marking an antigen for an immune response or marking dead cells for recycling (i.e., causes the phagocyte to "relish" the marked cell). Opson in ancient Greece referred to the delicious side-dish of any meal, versus the sitos, or the staple of the meal. Opsonin can be used to reference molecules that perform three functions: 1) acting as binding enhancers for the process of phagocytosis, including antibodies and complement, 2) activating the complement system, 3) targeting a cell for destruction through the action of natural killer (NK) cells.
Opsonization (also, opsonisation) is the molecular mechanism whereby molecules or microbes are chemically modified to have stronger interactions with - to be more "delicious" to - cell surface receptors on phagocytes and NK cells. With the antigen coated in opsonins, binding of the antigen to immune cells is greatly enhanced.
All cell membranes both have negative charges (Zeta potential) which makes it difficult for two cells to come close together. When opsonins bind to their targets they boost the kinetics of phagocytosis by favoring interaction between the opsonin and cell surface receptors on immune cells. This overrides the negative charges from cell membranes. This principal holds true for clearance of pathogens as well as dead or dying self cells.
Opsonization also mediates phagocytosis via signal cascades from cell surface receptors.
- Barret, James (1980). Basic Immunology and its Medical Application (2 ed.). St.Louis: The C.V. Mosby Company. ISBN 0-8016-0495-8.
- Roos, Anja; Wei, Xu; Castellano, Giuseppe; Nauta, Alma J.; Garred, Peter; Daha, Mohamed R.; van Kooten, Cees (2004). "A pivotal role for innate immunity in the clearance of apoptotic cells". Eur. J. Immunol. 34 (4): 921–929.
- Zhang, Youxin; Hoppe, Adam D.; Swanson, Joel A. (2010-11-09). "Coordination of Fc receptor signaling regulates cellular commitment to phagocytosis". Proceedings of the National Academy of Sciences 107 (45): 19332–19337. doi:10.1073/pnas.1008248107. ISSN 0027-8424. PMC 2984174. PMID 20974965.