Table 11.
Islet-Targeting Peptides
| Isolation methoda | Peptide Sequenceb,c,d | Target Cell | Applications and Notes |
|---|---|---|---|
| Ex vivo panning against freshly isolated rat pancreatic islets | LSGTPERSGQAVKVKLKAIP75 (RIP1) GAWEAVRDRIAEWGSWGIPS75 (RIP2) |
β-cells (RIP1) Non-specific binding (RIP2) |
Note: Radiolabeled RIP1 phage was shown to home to islets in vivo.409 |
| In vivo panning in male C57BL/6 mice followed by laser pressure catapult microdissection (LPCM) of pancreatic islet sections | CVSNPRWKC408 CHVLWSTRC408 |
vasculature of islets of Langerhans |
Oligonucleotide Delivery: Peptide-polymer carrying luciferase DNA transduced MS1 cells in culture.410 Note: EphA4 and EphA2 have been suggested as the receptors. |
| Ex vivo panning on cell suspensions from solid tumors of RIP1-Tag2 mice and then in vivo panning identifying phage homing to tumors using a T7 phage library | CRGRRST315 (RGR) CRSRKG315 (RSR) CKAAKNK315 (KAA) CKGAKAR315 (KAR) FRVGVADV315 (VGVA) |
RGR: hyperplastic & tumor vasculature of pancreatic islets (endothelial cells & pericytes) RSR: hyperplastic vasculature of pancreatic islets (endothelial cells & pericytes) KAA: tumor vasculature of pancreatic islets (endothelial cells & pericytes) KAR: tumor pancreatic islets VGVA: hyperplastic & tumor pancreatic islets |
Therapeutic Applications: Combination treatment with RGR peptide-anti-CD40 antibody and murine IL-2-RGR peptide fusion protein increased survival in RIP1-Tag5 mice, and 80% of mice treated with the combination treatment plus adoptive transfers of anti-Tag CD4+ and CD8+ T cells survived long-term.316 Note: PDGFRβ has been suggested as the receptor for the RGR peptide. |
| Ex vivo panning on cell suspensions from angiogenic islets of RIP1-Tag2 mice and then in vivo panning isolating phage that homed to angiogenic islets | CEYQLDVE315 (EYQ) | hyperplastic pancreatic islets |
a
All libraries are pIII phage libraries unless otherwise noted.
b
Cysteine residues that form disulfide bonds are indicated in bold.
c
Common peptide names that have been used in the literature are indicated in parentheses next to the peptide sequence.
d
Peptides clustered in the same cell in this table were isolated in the same selection experiment.