"Following phosphorylation of the tyrosine the proteins growth factor receptor-bound protein 2 (Grb2) Grb2-related adaptor downstream of Shc (Gads) and p85 subunit of phosphoinositide 3-kinase may bind to pYMNM (where pY is phosphotyrosine) via their Src homology 2 (SH2) domains leading to downstream signaling to distinct immune pathways. These three adaptor proteins bind to the same site on CD28 with variable affinity"xsd:string