Fig. 3. A, a pH sensitive polymer (MGlu-HPG) modified cationic
liposomes (TRX) for efficient antigen delivery and activation of
dendritic cells [52]. B, the drug is released when exceeded the
liposome phase transition temperature [54].
To grasp the particularity of
tumor environment or immune cells, it is helpful to establish an
efficient immune induction system or drug delivery system by modifying
different targeted ligands on liposomes. Sakurai et al. established a
new drug delivery system for malignant pleural mesothelioma (MPM) cells
with high expression and high affinity with HA receptor CD44 for the
treatment of MPM [55]. The drug delivery system connects cationic
liposomes and HA derivatives through the reductive amination of carboxyl
and amino groups, which improves the targeting effect of drug therapy.
DC-SIGN is known to be pathogen-associated molecular patterns (PAMPs)
receptor and the C-type lectin receptor that can recognize and combine
mannose structure and fucose structure. Martine et al. generated a
liposome containing the glycan Lewis (Le)X to target
DC with tumor antigen [56]. The glycol-liposome increased the
targeting of the drug to DC-SIGN, enhanced the uptake of liposome
antigen conjugate by DC, and ensured the presentation of tumor antigen
in MHC molecule.