<article_title>Antibody</article_title>
<edit_user>TimVickers</edit_user>
<edit_time>Friday, March 16, 2007 4:51:26 PM CET</edit_time>
<edit_comment>/* Research applications */ add image</edit_comment>
<edit_text>Research applications
<strong>[[Image:FluorescentCells.jpg|thumb|right|300px|[[Immunofluorescence]] image of the eukaryotic [[cytoskeleton]]. [[Actin]] filaments are shown in red, [[microtubule]]s in green, and the [[cell nucleus|nuclei in blue]].]]
</strong>In research, antibodies are used in a number of applications. The most common application is the identification and localization of intracellular and extracellular proteins. Antibodies may be used to differentiate cell types (see flow cytometry), to separate proteins (and anything bound to them) from the other molecules in a cell lysate (See immunoprecipitation), to identify proteins (See Western blot), or to examine protein expression (See immunohistochemical staining and immunofluorescence).&lt;ref name=Janeway6/&gt;</edit_text>
<turn_user>Quantockgoblin<turn_user>
<turn_time>Friday, March 16, 2007 5:11:11 PM CET</turn_time>
<turn_topicname>Why "Y" shaped</turn_topicname>
<turn_topictext>Just quick question - why are antibodies "Y" shaped. From a layman's perspective, it seems to me that only one half of the Y is need for an antibody to work. That is, it seems to me that only one receptor on one of the arms is needed to binding to the antigen. Does two arms result in a simple doubling the number of binding sites, so as to double the number of "capture site" per molecule, or is there something more subtle to it all? Thanks -- Quantockgoblin 17:11, 16 March 2007 (UTC) There's two quick answers, which I'm unclear how pertinent they'd be to the article, since they're essentially teleologic. 1) Binding of bivalent immunoglobulins of multiple epitope specificities allows for the formation of immune complexes 2) Activation of Fc receptors on effector cells (B cells, macrophages, etc.) may require cross-linking Jbarin 00:42, 7 May 2007 (UTC) -&gt; A third comment should be added to the question: Working with single-chain antibodies – a form of antibodies modified by biotechnological means, which possess only one binding domain - one does observe a significant reduction in the strength of binding of the single-chain antibody to its antigen ias compared with the original antibody having two binding sites - This observation strongly suggests that the two binding sites are also needed to improve the strength of binding. Kischel 22:45, 22 September 2007 (UTC)</turn_topictext>
<turn_text>Just quick question - why are antibodies "Y" shaped. From a layman's perspective, it seems to me that only one half of the Y is need for an antibody to work. That is, it seems to me that only one receptor on one of the arms is needed to binding to the antigen. Does two arms result in a simple doubling the number of binding sites, so as to double the number of "capture site" per molecule, or is there something more subtle to it all? Thanks -- </turn_text>