HAMSTER ANTI MOUSE CD278

Hamster anti Mouse CD278, clone C398.4A recognizes CD278 also known as ICOS (inducible T cell co-stimulatory molecule) or H4. CD278 is a member of the CD28 family (Hutloff et al. 1999) which also contains the immune attenuator CTLA-4. CD278 expression is found following T cell activation (Yoshinaga et al. 1999) and is able to co-stimulate T cell proliferative responses. ICOS binds to ICOS ligand which is expressed on antigen presenting cells. This ICOS/ICOSL interaction activates PI3K/AKT, MAPK and NKFB signalling pathways in a manner distinct from that acitvated via CD28. In a larger focus ICOS signaling plays a role in several physiological processes such as T follicular helper cell induction and maturation, antibody affininty maturation and regulation of T helper cell inflammatory responses.