This article includes a list of references, related reading or external links, but its sources remain unclear because it lacks inline citations. Please improve this article by introducing more precise citations where appropriate. (October 2009)

Autocrine signaling is a form of signaling in which a cell secretes a hormone or chemical messenger (called the autocrine agent) that binds to autocrine receptors on the same type of cell, leading to changes in the cells.^{[citation needed]} This can be contrasted with paracrine signaling, intracrine signaling, or classical endocrine signaling.

[edit] Examples

An example of an autocrine agent is the cytokine interleukin-1 in monocytes. When this is produced in response to external stimuli, it can bind to cell-surface receptors on the same cell that produced it.^{[citation needed]}

Another example occurs in activated T cell lymphocytes, i.e. when a T cell is induced to mature by binding to a peptide:MHC complex on a professional antigen presenting cell and by the B7:CD28 costimulatory signal. Upon activation, "low affinity" IL-2 receptors are replaced by "high affinity" IL-2 receptors consisting of α, β, and γ chains. The cell then releases IL-2 which binds to its own new IL-2 receptors, causing self-stimulation and ultimately a monoclonal population of T cells. These T cells can then go on to perform effector functions such as macrophage activation, B cell activation, and cell-mediated cytoxicity.^{[citation needed]}

[edit] See also

• Paracrine signaling
• Intracrine
• Endocrine system

[edit] External links

• 2140799033 at GPnotebook
• MeSH Autocrine+signaling
• "Autocrine versus juxtacrine signaling modes" - illustration at sysbio.org

This cell biology article is a stub. You can help Wikipedia by expanding it. v • d • e