Hepatitis B surface antigen expression in NT-1 cells of tobacco using different expression cassettes

Nicotiana tabacum 1 (NT-1) cells were transformed with four different expression cassettes of hepatitis B surface antigen (HBsAg). The transformed nature of the cells was confirmed by polymerase chain reaction. The expression levels were assayed by enzyme linked immunosorbent assay. The expressivities varied among the different cassettes and the maximum expression of 16.6 ng/g (f.m.) of cells was noted in pEFEHER transformed cells. Salicylic acid (100 microM) treatment resulted in 1.8 fold increase of expression in pEFEHBS transformed cells. The effect of different concentrations of kanamycin and geneticin was studied on the growth of transformed cells and HBsAg expression. The cell growth was optimum at lower concentrations of the antibiotics, and the maximum expression was noted at 200 mg/cubic dm of kanamycin.