title: Exogenous chondroitin sulfate glycosaminoglycan associate with arginine-rich peptide-DNA complexes to alter their intracellular processing and gene delivery efficiency.
abstract: Arginine-rich peptides have been used extensively as efficient cellular transporters. However, gene delivery with such peptides requires development of strategies to improve their efficiency. We had earlier demonstrated that addition of small amounts of exogenous glycosaminoglycans (GAGs) like heparan sulfate or chondroitin sulfate to different arginine-rich peptide-DNA complexes (polyplexes) led to an increase in their gene delivery efficiency. This was possibly due to the formation of a 'GAG coat' on the polyplex surface through electrostatic interactions which improved their extracellular stability and subsequent cellular entry. In this report, we have attempted to elucidate the differences in intracellular processing of the chondroitin sulfate (CS)-coated polyplexes in comparison to the native polyplexes by using a combination of endocytic inhibitors and co-localization with endosomal markers in various cell lines. We observed that both the native and CS-coated polyplexes are internalized by multiple endocytic pathways although in some cell lines, the coated polyplexes are taken up primarily by caveolae mediated endocytosis. In addition, the CS-coat improves the endosomal escape of the polyplexes as compared to the native polyplexes. Interestingly, during these intracellular events, exogenous CS is retained with the polyplexes until their accumulation near the nucleus. Thus we show for the first time that exogenous GAGs in small amounts improve intracellular routing and nuclear accumulation of arginine-based polyplexes. Therefore, addition of exogenous GAGs is a promising strategy to enhance the transfection efficiency of cationic arginine-rich peptides in multiple cell types.
authors: CSIR-Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110020, India.
authors: Rangeetha J
authors: RJ
authors: Naik
authors: CSIR-Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110020, India.
authors: Rajpal
authors: R
authors: Sharma
authors: CSIR-Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110020, India.
authors: Daniel
authors: D
authors: Nisakar
authors: CSIR-Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110020, India.
authors: Gunjan
authors: G
authors: Purohit
authors: CSIR-Institute of Genomics and Integrative Biology, Mathura Road, Delhi 110020, India. Electronic address: mganguli@igib.res.in.
authors: Munia
authors: M
authors: Ganguli
mesh_terms: D000818:Animals; D001120:Arginine / Q000737:chemistry / Q000378:metabolism*; D016466:CHO Cells; D057846:Cell-Penetrating Peptides / Q000737:chemistry / Q000378:metabolism*; D002809:Chondroitin Sulfates / Q000737:chemistry / Q000378:metabolism*; D006224:Cricetinae; D003412:Cricetulus; D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D004705:Endocytosis / Q000502:physiology*; D005434:Flow Cytometry; D018014:Gene Transfer Techniques; D006801:Humans; D015151:Immunoblotting; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism*
chemical_list: D057846:Cell-Penetrating Peptides; D010446:Peptide Fragments; C038142:chondroitin sulfate glycosaminoglycan; D002809:Chondroitin Sulfates; D004247:DNA; D001120:Arginine
keywords: Arginine-rich peptide; Gene delivery; Glycosaminoglycan; Trafficking