Preparation and transfection evaluation of modified multifunctional envelope-type nano device -DNA nanocomplexes based on low molecular weight protamine.

Objective(s): Gene therapy is a hopeful approach for treatment of a wide range of life threatening disease from infectious and inherited diseases to cancer. Multifunctional Envelope-type Nano Device (MEND) is a new carrier as non-viral genetic vector. Moreover, associating peptide structures with the nuclear localization signals (NLSs), which contains various functional groups enables them to condense DNA and specifically transfer genetic material to the nucleus. Materials and Methods: In this study, two forms of low molecular weight protamine (LMWP) were used for preparation of MEND carrier. The MEND carriers were then targeted with GE11 ligand to obtain T-MEND structure. The size distribution of the resulting nanoparticles, as well as their transfection efficiency and cytotoxicity, were investigated on the A549 cell line. Results: Results demonstrated that the size of polyplex carrier's formulation by both peptides (VV45 and VV32) was below 200 nm and MEND formulations were between 200-300 nm. T-MEND formulations contained VV32 and VV45 peptides showed slightly higher transfection than similar MEND formulations. Also, MEND formulation showed increased transfection efficiency compared to similar PD complexes. The result of metabolic activity test showed that MEND lipopolyplex did not represent any remarkable cytotoxicity. Conclusion: It can be concluded that multifunctional carriers designed based on LMWP are considered as the safe carrier for gene delivery. Presence of protamine and targeted ligand in the nanoparticulate structure did not increase the risk of cytotoxicity of carriers. So, MEND and T-MEND lipoplexes showed low cytotoxicity and acceptable transfection efficiency at the level of PEI 25 kDa. [ABSTRACT FROM AUTHOR]