Expression of bovine interleukin-2 in insect cells by recombinant baculovirus.

Bovine interleukin-2 (bIL-2) was expressed in insect cells infected with recombinant baculovirus. The cDNA for bIL-2 was amplified by reverse transcriptional polymerase chain reaction and recombinant baculovirus was constructed by homologous recombination. The recombinant baculovirus was plaque-purified, amplified, and then infected to Sf9 cells for expression of recombinant bIL-2 (rbIL-2). In result, the protein band corresponding to rbIL-2 could be detected on SDS-PAGE with coomassie brilliant blue staining and on immunoblot analysis reacted with mouse antiserum against bIL-2. In addition, cell proliferation assay for bIL-2 activity demonstrated that the culture supernatant of Sf9 cells infected with recombinant baculovirus enhanced the proliferation of bovine peripheral blood mononuclear cells in a dose-dependent manner.