Cloning And Expression Of Human Interleukin-4 Gene In Bombyx Mori Cells, Larvae And Pupae Of Silkworm As Reactors

Human interleukin-4 (hIL-4), a single-chain polypeptide of 129-amino acid, has wide potent applications. Using RT-PCR to clone hIL-4 gene from PBMC after activated by LPS. For mass production of hIL-4, Bombyx mori baculovirus expression vector system was adopted in this experiment. In order to increasing hIL-4 expression in Bombyx mori baculovirus expression vector system, The hIL-4 gene (460bp) was inserted into Bombyx mori baculovirus transfer vector pBacPAO and co-transfected with linearized DNA of Bm-BacPAK6 virus into BmN cells. The homologous recombination occurred inside the cells, and the recombinant virus (named BacPAK-hIL-4) was identified by PCR. The recombinant virus BacPAK-hIL-4 infected the BmN cells, fifth instars and pupae of Silkworm expression product was run in the SDS-PAGE, and its immunoreactivity was determined by using ELISA. The bio-activity of the protein product was determined by using human PBMC T cells proliferation test in vitro. The expression activity achieved maximum at the 72h hour in BmN cells and at 96h hour in larvae after infection according to cell activity results. The expression product could enhance the proliferation of the human T cell.