Proposed model for integration of TCR and CCR7-triggered signals. During an early promigratory phase of an ongoing antigenic response, CD4⁺ T cells undergo sequential encounters with pMHC-presenting DCs (left panel). During this period, T cells are exposed to TCR- and CCR7 (in addition to other GPCR)-derived signals, both of which activate PI3K, DOCK2-Rac, and Ras. Active Rac- and Ras-GTP contribute to enhanced MEK-ERK activation leading to up-regulation of early activation markers, such as CD69, and rapid production of IL-2 (right panel).