System for the production of transgenic BY2 cells in bioreactors

In this work, we analyse culture conditions, in flask and bioreactor, in order to produce human Placental Lactogen (hPL), a peptidic hormone of 22 KDa synthesised in the placenta. The use of peptidic growth factors to augment β cell mass is one of the strategies developed to diabetes treatment. The hPL belongs to the group of growth factors mentioned above, so it could be useful to improve beta cell survival after their transplantation in diabetic patients. BY2 cells batch cultures were carried out in an autoclavable 5 litre reactor from Sartorius®. Biomass generation (fresh and dry), intracellular and extracellular hPL amount, total soluble protein amount and pH tendency were checked along the culture. We obtained a 33-fold increase in biomass at 192 h of culture, achieving a total of 470 μg of recombinant lactogen. The biological activity assay showed that the recombinant protein produced in BY2 cells was as active as the hPL from the NIH (National Institute of Health, USA).