ABSTRACT
The immune system needs to provide a constant vigil over tissues throughout the body in order to mount a rapid and effective response to foreign invasion by pathogens. Leukocytes, and in particular lymphocytes, play a crucial role in this process by providing immunosurveillance of tissues and by co-ordinating a rapid inflammatory response when foreign antigen is detected. Chemokines are small proteins containing four conserved cysteines, linked by disulphide bonds. They are subdivided into families depending on the relative position of cysteine residues within the mature protein. CXC or alpha chemokines are distinguished by the presence of an amino acid between the first two cysteines whereas the cysteines are adjacent in CC or beta chemokines. Chemokines are produced by a wide variety of cell types, including immune cells and endothelial cells, and may be rapidly induced following stimulation by a variety of agents.
