Human keratinocyte growth factor-1 (hKGF-1), a member of the fibroblast growth factor (FGF) family, plays crucial roles in organ development, cell proliferation, wound healing, and tissue repair, representing one of the most effective and specific growth factors for skin repair. However, obtaining recombinant hKGF-1 remains challenging due to its universally low expression efficiency in vitro. This study employs the Bombyx mori baculovirus expression system to establish a technological platform that utilizes the economically important insect Bombyx mori as a bioreactor for high-efficiency and low-cost expression and production of recombinant human keratinocyte growth factor 1 (hKGF-1) protein, ultimately achieving high-level expression of hKGF-1 in Bombyx mori ovary cell line (BmN). In this study, we optimized the hKGF-1 sequence based on the codon preference of baculovirus. By fusing hKGF-1 with polyhedrin (highly expressed in this system) and adding extra promoters and enhancers, we significantly improved the expreesion level of hKGF-1 in Bombyx mori cells. The results demonstrated that the aforementioned strategies significantly enhanced the expression level of hKGF-1 in Bombyx mori cells. SDS-PAGE and Western blotting results revealed that the highest hKGF-1 expression (accounting for 8.7% of total cellular protein) was achieved when the Polh promoter was combined in tandem with the P6.9 promoter and hKGF-1 was fused with a 15-residue polyhedrin fragment for co-expression. The optimal harvest time was determined to be 120 h post transfection. This study achieved the efficient expression of hKGF-1 in Bombyx mori cells, establishing an ideal technological platform for the industrial utilization of recombinant hKGF-1. The developed methodology not only provides valuable technical references for the production of other growth factors and complex proteins, but also demonstrates significant implications for employing silkworms as bioreactors for recombinant human protein expression.
Bombyx/metabolism* ; Animals ; Baculoviridae/metabolism* ; Humans ; Fibroblast Growth Factor 7/biosynthesis* ; Recombinant Proteins/genetics* ; Cell Line ; Genetic Vectors/genetics*

Recently, more research about the plant bioreactor expressing genes encoding human proteins was reported. In the present study, the cDNA of the human gene keratinocyte growth factor 2 (KGF2) was replaced with plant preferred codons by PCR, and the modified full-length cDNA was cloned into the plant expression vector pCAMBIA-YO containing the oil-body promoter. The fusion construct pCAMBIA-YO-KGF2 was transformed into Brassica napus by Agrobacterium tumefacien-mediated cotyledon transformation method. The transgenic seedlings were identified by PCR, Southern and western blot analysis all showed that KGF2 gene was successfully expressed in in transgenic Brassica napus.
Brassica napus ; genetics ; metabolism ; Cloning, Molecular ; DNA, Complementary ; genetics ; Fibroblast Growth Factor 7 ; biosynthesis ; genetics ; Genetic Vectors ; genetics ; Humans ; Plants, Genetically Modified ; genetics ; Rhizobium ; genetics ; Transformation, Genetic