Comparison of the cultivation of wild and transfected Drosophila melanogaster S2 cells in different media

Insect cells have been increasingly employed for the production of recombinant proteins. One of the most widely used dipteran cells in transfection studies is the Schneider 2 (S2) cell line, established from Drosophila melanogaster embryonic tissue. In this work, the growth and proliferation of wild and transfected S2 cells expressing the G glycoprotein from rabies virus (GPV) were compared employing different culture media. For the transfected (S2AcGPV2) cell contruction, the plasmid pGPV encoding the sequence of interest and the vectors pAc 5.1/V5-His A under the control of the Drosophila actin promoter were utilized. The selection vector pCoHygro carrying genes coding for hygromicin-inactivating enzymes was also employed and the cells were transfected using lipofectin. Due to wide utilization of TNM-FH and TC100 media (both requiring supplementation with fetal bovine serum) for insect cells, their low cost and the low protein content of SF900II medium, the,se three media and the mixture TNM-FH-SF900II (1:1) were evaluated for the choice of a suitable media for S2 cells. The results indicated that the wild and the transfected cells presented different growth characteristics in the distinct media. In SF900II medium, larger accumulation and consumption of lactate were observed for the wild cell culture. In TC100, however, S2AcGPV2 cells did not produce lactate. In TNM-FH, the S2 cells presented lower growth rate (mu(max)=4.0078 h(-1)) when compared to the other media (mu(max)=0.0375 h(-1) and mu(max)=0.0112 h(-1) for SF900II and TC100, respectively), with an accentuated viability drop during the first days of culture. The mixture of TNM-FH and SF900II at a 1:1 volume ratio resulted in cell growth (mu(max)=0.0377 h(-1)) similar to that observed in SF900II medium only, allowing significant culture media cost reduction. Transfected cells could not be adapted to TNM-FH medium. Cell growth of S2AcGPV2 cells in TC 100 medium (mu(max)=0.0151 h(-1)) was lower than in SF900II medium (mu(max)=0.0407 h(-1)).