Cytokine

Patent Pending Cytokines (Greek cyto-, cell; and -kinos, movement) are a broad and loose category of small proteins (~5–20 kDa) that are important in cell signaling - they are released by cells and affect the behavior of other cells, and sometimes the releasing cell itself. Cytokines include chemokines, interferons, interleukins, lymphokines, tumour necrosis factor but generally not hormones or growth factors.