Here's why:
* Cytokines are small proteins that act as signaling molecules, primarily in the immune system. However, they are produced by a wide range of cells, not just immune cells.
* Hormones are typically produced by specialized glands and travel through the bloodstream to target cells in other parts of the body.
* While some cytokines can act like hormones, they are generally considered to be more localized in their effects and often act within the same tissue or organ where they are produced.
So, while both hormones and cytokines are signaling molecules, cytokines are a broader category that includes those produced by many different cell types.
