Which of the following is an example of autocrine signaling?
A) An NK cell responding to IL-12 produced by a macrophage.
B) A macrophage responding to TNF made by the same macrophage.
C) A T helper cell responding to IL-2 produced by a neighboring T cell.
D) A neutrophil responding to IL-1 produced by vascular endothelial cell.

Question

Quizplus · Accepted Answer

Autocrine signaling occurs when a cell responds to a product that same cell made. In this example the macrophage has receptors for TNF, and it produces the TNF that binds to its own TNF receptors. The other options are examples of paracrine signaling, in which a cell responds to a product produced by a nearby cell. The third type of signaling is endocrine signaling, in which a cell responds to a product made by a distant cell.

Which of the Following Is an Example of Autocrine Signaling