Interleukiine

Interleukins (IL) are a group of signaling molecules, or cytokines, that were first discovered to be expressed and secreted by white blood cells (leukocytes). The term "interleukin" is derived from their initial characterization as factors that promote the growth and differentiation of immune cells. However, it is now known that interleukins are expressed by a wide variety of cells and have diverse effects on numerous cell types, not just leukocytes.

Interleukins play a crucial role in the immune system by regulating immune responses, including the development and differentiation of T, B, and hematopoietic cells. They are involved in both pro-inflammatory and anti-inflammatory processes, and their effects can be either stimulatory or inhibitory, depending on the specific interleukin and the context in which it is acting. There are currently over 40 identified interleukins, each with unique functions and receptors.

The structure of interleukins varies, but they generally consist of a single polypeptide chain that can form homodimers or heterodimers. Interleukins exert their effects by binding to specific receptors on the surface of target cells, which then trigger intracellular signaling pathways. The receptors for interleukins are typically composed of multiple subunits, which can be shared among different interleukins, leading to complex and overlapping signaling networks.

Dysregulation of interleukin signaling has been implicated in various diseases, including autoimmune disorders, inflammatory diseases, and cancer. As a result, interleukins and their receptors have become important targets for the development of therapeutic agents. For example, drugs that block the activity of specific interleukins, such as tocilizumab (which targets IL-6) and ustekinumab (which targets IL-12 and IL-23), have been approved for the treatment of rheumatoid arthritis and psoriasis, respectively.