Cellular uptake of DNA–chitosan nanoparticles: The role of clathrin- and caveolae-mediated pathways

Development of a gene-activated scaffold platform for tissue engineering applications using chitosan-pDNA nanoparticles on collagen-based scaffolds

“…It is hypothesized that chitosan-based gene delivery vectors enter cells via charge-mediated endocytosis [47], therefore, chitosan-pDNA nanoparticles need to be positively charged to bind to the negatively charged cell membrane, and have a diameter of <200nm to enable endocytosis [43]. AFM images revealed that polymeric chitosan (PCS)-pDNA nanoparticles appear homogenous in size with an average diameter of ~190 nm while oligomeric chitosan-(OCS)-pDNA nanoparticles have a less defined shape and a smaller diameter of ~120 nm.…”

“…The difference in morphology is likely due to the use of a cross-linker (sodium tripolyphosphate (TPP)) in the formulation on PCS-pDNA nanoparticles which causes a controlled ionotropic gelation of the nanoparticles [19,48]. Without TPP PCS-pDNA nanoparticles were in the micron size range and therefore unsuitable for gene delivery [43,47]. TPP did not cause changes in size in the formulation of OCS-pDNA nanoparticles and thus was not used which explains their irregular shape.…”

“…It has been shown that PCS-pDNA nanoparticles enter cells predominantly through the clathrin-mediated endocytosis pathway which carries cargo through the cytoplasm in acidic endosomes [47]. It is thought that polymers that are capable of buffering this acidic environment can cause an increase in osmotic pressure and rupture the endosome, liberating the delivery vector and its gene cargo.…”

“…Interestingly, OCS-pDNA nanoparticles are reported to enter cells via clathrin-independent pathways, namely the caveolae route of endocytosis. Much less is known about this route of entry but a different entry mechanism may explain the difference in transfection efficiency seen by the two types of chitosan [47].…”

Low Molecular Weight Chitosan (LMWC)-based Polyplexes for pDNA Delivery: From Bench to Bedside

“…Thus, CME and CvME are the best-characterized types of endocytosis in non-viral gene therapy field, although CvME pathway is less well understood [56]. It is described that LMWC based polyplexes could enter the cell via these two endocytic pathways, however, there is a lack of consensus in the scientific area [53,57]. The diversity that exists in the published results may be attributed to the fact that many factors determine the uptake pathway of Ch-pDNA polyplexes.…”