Introduction/Objectives: Purification of recombinant Factor VIII from mammalian cells poses remarkable challenge, because of its suboptimal yield and significant1y high
cost. Bacalovirus derived expression in insect cells is an appropiate system to overcome these limitations. However, several reports have concluded that Sf9 cells are not suitable for expression of structurally correct factor VIII (fVIII). We have developed a cDNA construct encoding chimeric, full-length human fVIII in which dispensable B-domain has been replaced with significantly shorter B-domain derived from its ortholog in Fugu rubripe. This cDNA was successfully applied for expression and purificacion of active fVIII protein in Trichoplusia ni insect cells, known as High Five (Invitrogen)