Table 3.

Intracellular trafficking can be enhanced by the incorporation of specific functional groups onto the vector backbone

Endosomal escape	Mechanism	Sequence	Refs.
INF (influenza virus-derived sequence)	Endosomolytic at pH 5.0 by adopting an amphipathic α-helical conformation	GLFEAIEGFIENGWEGMIDGWYG (or GGC)	[41]
KALA	PH-dependent α-helical conformational change disrupts endosome	WEAKLAKALAKALAKHLAKALAKALKACEA	[43]
Nuclear localization	Nuclear binding protein	Sequence	Refs.
SV40	Importin-α	PKKKRKV	[53]
M9	Transportin	GNQSSNFGPMKGGNFGGRSSGPYGGGGQYFAKPRNQGGY	[54]
Pharmacological agents	Effect		Refs.
Dexamethasone spermine	Reduces cytokine production, reduces inflammation		[47]
Chloroquine	Enhances endosomal escape, but limited by systemic toxicity		[48]