Model of T-cell TSP-1 and its interactions with cell-surface receptors. TSP-1 is associated to CRT/CD91 and/or integrin at the NH2-terminal domain before adhesion, as indicated by small circles. Adhesive interactions with ECM components or ICAM-1 via integrins trigger interaction of the C-terminal domain of TSP-1 with CD47 (small circle) and up-regulate TSP turnover. Ligation of TCR/CD3 inhibits internalization of TSP-1, CRT, and CD91 and focuses TSP-1 onto its cell-surface receptors.