Primary objectives of gene therapy are to correct the genetic defects that underlie a disease process and to provide supplemental
therapeutic modality through genetic engineering. Over 75% of current gene therapy is performed using viruses as gene
delivery vehicles. However, with viruses, there are serious concerns over the issues of toxicity, immunogenicity, payload gene
size limitations, and difficulty in scale up for industrial production. Non-viral vectors therefore have attracted attention from
academic and industrial point of view. Among the non-viral vectors, polymeric systems offer several important advantages.
First, polymers are tremendously versatile and can provide physical, chemical, and biological properties that are necessary for
gene delivery applications. Second, polymers can be synthesized in parallel synthesis pathways for high-throughput screening of
biocompatibility and transfection efficiency. Third, various formulations, designs, and geometrics can be made from polymeric
materials for specific types of gene delivery applications. Moreover, the surface chemistry of polymers can be easily modified
with biological ligands for site specific targeting in the body. However, some non-degradable polymers accumulate in the body
resulting in the cytotoxicity and thus the reduction in their gene transfer ability. Even though, low molecular weight polymers,
which can be eliminated via kidney is an alternative choice, exhibits lower colloidal stability and DNA condensation due to their
reduced number of electrostatic interactions thus reduced transfection efficiency.
As biodegradable polymers are designed to contain a combination of various functional components, it is likely that engineered
systems for non-viral gene delivery, especially with the application of biodegradable ester linkage will eventually be constructed.
This biodegradable linkage approach to vector development is giving way to a safety profile where low molecular weight
polyethylenimines are couples with diacrylate linkers to yield high molecular weight poly(ester amine)s (PEAs) with reduced
cytotoxicity and high transfection efficiency. For example, the initial emphasis on identifying materials that bind and condense
nucleic acids may have underappreciated the importance of their subsequent cellular uptake; attention has now turned to vectors
with a hydrophobic, biodegradable cross linker such as polycaprolactone diacrylate  or hydrophilic, biodegradable cross linkers
such as glycerol dimethacrylate  and glycerol triacrylate  whose chemical structure with ester linkage allowed the controlled
fashioned degradation with suitable nucleic acid condensation, following cellular uptake and thus gene delivery ability. The need
for a safety and biocompatibility approach extends to in vitro investigations, as modifications intended for in vivo applicability
can significantly affect both in vitro and in vivo performance.
Dr. Rohidas B. Arote has been studied with gene delivery for more than 7 years. He has been awarded as ?Young Scientist? in the field of Gene
Therapy. He published 35 international and 2 domestic papers related to non-viral gene delivery. Since 2007, he published more than 25 international
publications on development of non-viral gene carrier. Recently he synthesized novel biodegradable poly (ester amine)s based on glycerol
dimethacrylate and low molecular weight polyethylenmine and this polymer showed significant transfection efficiency in gene silencing activity in
vitro as well in vivo for which he applied a patent in Korea. Currently he is a Assistant Professor at Seoul National University
Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals