Figure 1.

Schematic diagram of PNBs serving as a neuroprotective nanoformulation for acute ischemic stroke lesion theranostics. Both the “marker of self” membrane proteins in the shell of PNBs and their nano size facilitate specific delivery into stroke lesion microvascular vessels. Integrins such as α₂β₁, α₅β₁, α₆β₁, and α_Ⅱbβ₃ and the glycoproteins (GP) Ib-IX-V and GPVI impart the PNBs with intrinsic damaged vessel adhesive ability. The CD47 membrane protein could prevent phagocytosis by macrophages, while the CD55 and CD59 complement regulatory proteins may suppress complement system activation when PNBs circulate in the body.