What are cytokines, what do they do?
As proteins that are produced by white blood cells, cytokines perform several important functions that allow the body to operate at optimum levels. They are often created in response to the presence of some sort of bacterial infection. The term cytokine is derived from a combination of two Greek words - cyto meaning cell and kinos meaning movement. Cytokines are cell signalling molecules that aid cell to cell communication in immune responses and stimulate the movement of cells towards sites of inflammation, infection and trauma. They are released by cells and affect the behavior of other cells. Cytokines can also be involved in autocrine signaling. Cytokines include chemokines, interferons, interleukins, lymphokines, tumour necrosis factor but generally not hormones or growth factors (despite some terminologic overlap). Cytokines are produced by a broad range of cells, including immune cells like macrophages, B lymphocytes, T lymphocytes and mast cells, as well as endothelial cells, fibroblasts, and various stromal cells; a given cytokine may be produced by more than one type of cell. Each specialized T cell can be be characterized (to some degree) by … the cytokines they secrete. Th1 cells secrete IFN gamma while Th2 cells secrete IL4, IL5, IL9 and IL13. These are not the only cytokines they are capable of secreting, but these are the predominate ones. Cytokines are cell signalling molecules that aid cell to cell communication in immune responses and stimulate the movement of cells towards sites of inflammation, infection and trauma. The cytokine network. Cytokines have over time been given many different names most of which are still in use. You may come across the words lymphokines (cytokines produced by lymphocytes), leucokines (cytokines produced by all white blood cells), chemokines, monokines, interferons, interleukins and lymphotoxins. Cytokines are cell signalling molecules that aid cell to cell communication in immune responses and stimulate the movement of cells towards sites of inflammation, infection and trauma. Cytokines exist in peptide, protein and glycoprotein (proteins with a sugar attached) forms. Th2 cells mediate these functions by producing various cytokines such as IL-4, IL-5, IL-6, IL-9, IL-13, and IL-17E (IL-25) that are responsible for strong antibody production, eosinophil activation, and inhibition of several macrophage functions, thus providing phagocyte-independent protective responses. These cytokines also counteract the Th1 responses that allow for the Th2 responsiveness to IL-4. IL-4 signals through STAT6 to upregulate GATA3 expression, the master regulator of Th2 cell differentiation. Repression of this activity results in the development failure of IL-4 producing cells.
The term cytokine is derived from a combination of two Greek words - cyto meaning cell and kinos meaning movement.