Illustration of a mycobacterial infection. Mycobacteria (upper right, with cutaway view) infects a dendritic cell (upper left) which triggers the release of cytokines such as Interleukin-23 (lower left). Interleukin-23 (IL-23) is a heterodimeric cytokine which is an important part of the inflammatory response against infection. IL-23 binds via an interleukin receptor to a t-cell, activating the cell to fight the infection.