Cytokines are proteins which are produced by cells and function to serve as molecular messengers between cells. One of the important role of cytokines is to interact with the immune system to help in the regulation of the body’s response to infection and disease, in addition to mediating the normal cellular processes occurring within the body.
The immune system is complex and explaining how cytokines work can be quite difficult. In short, cytokines are firstly released by cells either directly into tissues or into the circulatory system. Next cytokines have to locate target immune cells and then interact/bind with the receptors that are present on these target cells. This specific interaction can trigger a cascade of signals taking place within the target cell that ultimately leads to altering its behaviour. However, inappropriate or overproduction of certain cytokines can lead to disease formation. For example; IL-1 and TNF-alpha are found to be produced in excess in rheumatoid arthritis patients, where there are involved in tissue destruction and inflammation.
The body is able to produce many different types of cytokines, all of which are diverse. Some of the commons classes of cytokines are listed below:
- Pro-Inflammatory & Immuno-Regulatory Cytokines: Examples are interleukins, interferons and TNF-alpha that function in the immune system.
- Differentiation & Growth Factors: These function primarily in development.
- Colony Stimulating Factors: These are responsible for stimulating the production of blood cells.
Cytokines can be essentially classified has being lymphokines, interleukins and chemokines, this classification is principally based on their cell of secretion, presumed function and their target of action. Some of the most common cytokines groups include.
- Interleukins: these were initially described by researchers as cytokines with presumed target that were principally leukocytes. However, now the vast majority of these are formed by T-helper cells and bear very little relation to their presumed function.
- Monokines: these are exclusively produced by monocytes, examples include IL-1 alpha, IL-1 beta, TNF-alpha, IFN-alpha, IFN-beta, G-CSF, M-CSF.
- Lymphokines: these are exclusively produced by lymphokines, examples include IL-2, IL-3, IL-4, IL-5, IL-6, GM-CSF, IFN-gamma.
- Interferons: these are involved in a large number of antiviral responses.
- Chemokines: these are responsible for mediating chemoattraction (known as chemotaxis) between cells.
- Colony stimulating factors: these are vital in supporting the growth of cells within semi-solid media, examples include M-CSF, G-CSF.
If you want to learn more about cytokines, their general properties and how there are able to use specific cell surface receptors in order to regulate the immune system, then please view our detailed cytokines tutorial section.
Most Popular Cytokine ELISA Kits
- Interferon-Gamma (IFN-Gamma) ELISA Kit
- Tumor Necrosis Factor-Alpha (TNF-Alpha) ELISA Kit
- Interleukin-1 Alpha (IL-1A) ELISA Kit
- Interleukin-4 (IL-4) ELISA Kit
- Interleukin-8 (IL-8) ELISA Kit
- Monocyte Chemotactic Protein-3 (MCP-3) ELISA Kit
- Macrophage Inflammatory Protein-1 Alpha (MIP-1 Alpha) ELISA Kit
- CXCL9 (MIG) ELISA Kit
- CXCL10 (IP-10) ELISA Kit
- CCL11 (Eotaxin) ELISA Kit
- Rantes (CCL5) ELISA Kit
- Resistin ELISA Kit