[Expression of oleosin-rhFGF9 fusion protein in Carthamus tinctorius and determination of hair regeneration and wound repair potential in mice].

The expression of fibroblast growth factor 9 (FGF9) recombinant fusion protein in Carthamus tinctorius was used to identify its effect on hair regrowth and wound repair system in mice, providing a basis for C. tinctorius as a plant bioreactor, and establishing a foundation for commercial applications of FGF9 fusion protein in hair regrowth and wound repair. The identified pOTBar-oleosin-rhFGF9 plasmid was transformed into Agrobacterium tumefaciens EHA105 by freeze-thaw method, and the oleosin-rhFGF9 gene was transformed into safflower leaves by A. tumefaciens mediated method. Transgenic safflower seedlings were then obtained by tissue culture. After basta screening, transgenic T₃ safflower seeds were obtained by grafting method, PCR verification and propagation. The expression of oleosin-rhFGF9 was detected by Western blot, and the content of oleosin-rhFGF9 fusion protein was 0.09% by using ELISA quantitative method. It was observed that 60 μg·L⁻¹ transgenic safflower oil had better effect on promoting NIH/3T3 cells proliferation in a certain dose-dependent manner. Sixty C57BL/6 mice were used to establish alopecia model and wound model respectively, and then were randomly divided into control group (treated with PBS or saline), negative group (treated with wild type safflower seed oil bodies, 60 g·L⁻¹), positive group (treated with FGF9, 0.054 g·L⁻¹), low dose group (treated with transgenic safflower oil bodies, 10 g·L⁻¹) and high dose group (treated with transgenic safflower oil bodies, 60 g·L⁻¹). The skin of all above-mentioned mice models were coated with soft adhesive manner every other day, 100 μL/time. After 15 days, the mice skin was cut and embedded for histological analysis. The hair regrowth experimental results showed that the hair of mice grew well, and the mice in high dose group had bushy hair, with significant effect on regeneration hair number as compared with the positive group. The healing was obvious in wound experiment, with significant healing effect in positive group, high dose group and low dose group as compared to blank control group. Furthermore, high dose group remarkably showed a better and higher healing effect than the positive group at day 5. Oleosin-rhFGF9 was successfully transformed into safflower, and T₃ transgenic safflower oil bodies expressed oleosin-rhFGF9 fusion protein were obtained, with the role of promoting hair regeneration and wound repair in mice.