Gene delivery to hair follicles by multifunctional envelope-type nano device

点击翻译按钮获取中文摘要

Head investigator of this project tried to develop novel gene delivery system to hair follicles of mice by topical application of non-viral gene delivery system octaarginine-modified multifunctional envelope-type nano device (R8-MEND). After treatment of mice back skin with the R8-MEND containing EGFP-encoding plasmid DNA or LacZ-encoding plasmid DNA, expression of EGFP protein and beta-gal positive staining image were observed in cross section of the skin treated with R8-MEND. Moreover, topical application of R8-MEND, which contained Bone morphogenetic protein type IA receptor (BMPRIA) -encoding plasmid DNA, was performed to back skin of 4 weeks old ICR mice. After 2 weeks of the treatment, position of hair follicles in the skin was almost the same as before treatment, although position of hair follicles of control mice was moved to upper region because of progress of hair cycle. It is suggested that topical application of R8-MEND-BMPRIA prolonged hair cycle. Then, head investigator t … More ried to inhibit the specific genes relating to growth and cycle of hair by delivery of siRNA against those genes via topical application of R8-MEND. However, no significant effect was observed. To know the reason why the siRNA delivery by R8-MEND was not effective, head investigator observed cross section of the skin treated by R8-MEND containing siRNA labeled with rhodamine. As a result, very a few siRNA was observed in the skin, indicating that improvement of siRNA delivery is necessary. Then, head investigator tried to delivery liposomes, which are the model of MEND, via iontophoresis. Head investigator found optimal size (>400nm) and surface charge (positive) of liposomes for transfollicular delivery of nano-particles via iontophoresis. Moreover, head investigator succeeded in transfollicular delivery of liposomes containing model drug solution (aqueous rhodamine) into skin via iontophoresis in vivo. Therefore, the delivery of R8-MEND containing siRNA should be achieved by this novel transfolicular delivery system in near future. Less