Table 2.
Delivery ligands targeting bone cells or bone marrow
| Ligand | Targeting feature | Ref |
|---|---|---|
| Calcitonin gene-related peptide (CGRP) | CGRP receptor on pOCs | 343 |
| Hyaluronic acid (HA) | CD44 on the surface of the osteoclasts and the CD44-rich bone marrow microenvironment | 343 |
| cRGDyk | α5β3-integrin on osteoclasts membrane | 334 |
| Aptamer CH6 | Osteoblasts | 19 |
| SDSSD | Osteoblast-specific factor 2 (OSF-2) | 346 |
| LLP2A | Binding integrin α4β1 to improve homing | 252 |
| CXCR4 or CXCR7 | Binding CXCL12 to promote homing to bone marrow | 20,329 |
| SKPPGTSS (SKP) | Possessing a partial amino acid sequence homology with a region of CD84 to promote homing | 332,333 |
| VTAMEPGQ (VQ) | Rat mesenchymal stem cells specific | 351,352 |
| EPLQLKM (E7) | Efficiently interact specifically with MSCs without any species specificity | 349,350 |