Figure 4.

In vivo evaluation of PBD-lipid effects on mRNA delivery. a) C57BL/6 mice were injected i.v. separately with the series of six 4A3-SC8 DLNPs formulated with different PBD-lipids at the same dose of 0.1 mg kg⁻¹ Luc mRNA and imaged by IVIS after 6 h (n = 2). Then organs were collected for bioluminescence and fluorescence imaging. b) Quantification of ex vivo Luc mRNA expression intensity in livers. c) Subcutaneous SUM159 breast tumor-bearing mice were injected intratumorally with 4A3-SC8&PEG2k5d DLNP at a dose of 0.05 mg kg⁻¹ Luc mRNA and imaged by bioluminescence and fluorescence (d) at 6 h post injection. Representative ex vivo bioluminescence (c) and fluorescence (d) images of harvested tumor and organs from SUM159 breast tumor-bearing mice sacrificed at 6 h post injection. (e) Time-dependent in vivo fluorescence images of mice bearing subcutaneous SUM159 breast cancer xenograft tumors after i.v. injection of 0.2 mg kg⁻¹ Luc mRNA loaded 4A3-SC8 DLNPs containing 50% PEGDMG & 50% PEG2k5d. Representative fluorescence images of harvested tumors and organs from SUM159 tumor-bearing mice sacrificed at 24 h post injection.