Figure 3.
Schematic illustration of some of the most important costimulatory and coinhibitory interacting pairs [121, 122]. They belong to two main families, the immunoglobulin superfamily (CD28–CD80/86 and ICOS–ICOS-L), shown in the top half of the figure, and the TNF superfamily, shown in the bottom half of the figure, each containing more than 25 already identified members [126]. The repertoire of cosignaling pathways contains both immune-stimulatory (green) and -inhibitory (red) specific pathways as well as some ambiguous ones.