TFRC and brain infarction: Another approach employs poly(γ-glutamic acid) and OX26 antibody (a monoclonal antibody that specifically targets the transferrin receptor (TfR), which is highly expressed on the surface of brain capillary endothelial cells (BCECs) forming the blood-brain barrier (BBB)) to form ginsenoside Rg1 nanoparticles that can traverse the BBB and alleviate cerebral infarction in diabetic rats, highlighting the versatility of peptide-mediated targeting even for brain diseases (Shen et al., 2017).