Cytokines are a broad class of small signaling proteins that include chemokines, interleukins, interferons, tumor necrosis factors, bone morphogenic proteins and lymphokines. They are defined as soluble factors produced by one cell to act on another cell, mainly functioning by binding to specific cell surface receptors. This leads to activation of intracellular signal cascades relating to processes such as infection, immune response, apoptosis, development, and cancer. In contrast to hormones, cytokines are more potent in smaller concentrations and can be produced by different cell types. Antibodies for specific cytokines are widely used and available from a number of sources. Use the provided filters to help simplify your search.