Endosome lysis

Leopold, P.L., Kreitzer, G., Miyazawa, N., Rempel, S., Pfister, K.K., Rodriguez-Boulan, E. and Crystal, R.G. (2000) Dynein-and microtubule-mediated translocation of adenovirus type 5 occurs after endosomal lysis. Hum. Gene Then, 11, 151-165. 

Leopold PL, Kreitzer G, Miyazawa N, Rempel S, Pfister KK, Rodriguez-Boulan E, Crystal RG (2000) Dynein- and microtubule-mediated translocation of adenovirus serotype 5 occurs after endosomal lysis. Hum Gene Ther 11 151-165... 

Synthetic peptides have also been developed that enhance the release of the peptide/DNA complexes from the endosome following endocytosis. Without a means of escaping the endosome, the endosomal-lysosomal pathway presents a major barrier to transfection via receptor mediated endocytosis. The use of endosomal lysis agents, such as membrane active lipids or peptides, is important in non-viral gene delivery systems. 

In case of local gastrointestinal treatments nucleic acid drugs shall be taken up by enterocytes, usually through endocytosis. The route of uptake determines, subsequently, nucleic acid trafficking and lifetime in the cell. Endocytosis is a multistep process involving binding, internalization, formation of endosomes, fusion with lysosomes, and lysis. The low pH and enzymes within... 

When a dendriplex reaches the target cell, it is internalized and den-driplex-containing endosomes are formed. Deprotonation of dendrimer surface groups, dendrimer destruction and nucleic acid release occurs when the pH changes from 7.4 (extracellular value) to 5.5 (intracellular value). The nucleic acid release occurs when endosomes undergo lysis (Figure 13.3). 

The technique of osmotic lysis of pinosomes (11) was more successful. Cells were allowed to endocytose in hypertonic medium containing fragment A and were then exposed to a hypotonic medium that swelled endosomes and, in some cases, released their contents into the cytosol. Twenty four hr later, [i C]leucine incorporation had been reduced by about 80% (Fig. 3). 

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