Abstract: The development of insect cell lines plays a significant role in research and application of virology and entomology. Two new cell lines, i.e., QB-Ha-E-1 and QB-Ha-E-5, were established from the embryonic tissue of Helicoverpa armigera (Lepidoptera: Noctuidae). The cell lines had been subcultured over 60 passages in TNM-FH medium supplemented with 10% fetal bovine serum. Each cell line has two major morphological types, round cells and spindle-shaped cells. DNA amplification fingerprinting (DAF) analysis indicated that DNA profiles of the two cell lines were similar but distinctly different from cell lines of several other insects, suggesting that both originated from the embryonic tissue of H. armigera. The cell doubling time of the 30th passages of QB-Ha-E-1 and QB-Ha-E-5 were 63.7 h and 66.9 h, respectively. Both the cell lines could be infected by H. armigera single nucleopolyhedrovirus (HaSNPV) with the infection rates of 86.6% and 56.5%, respectively, 4 d post infection (p.i.). Approximately 15% of the two cell lines were infected by Mamestra brassicae nucleopolyhedrovirus (MbNPV) 7 d p.i. The two cell lines had differential responses to Autographa californica multiple nucleopolyhedrovirus (AcMNPV) infection. The results from the fluorescent staining with DAPI and electrophoresis of genomic DNA indicated that QB-Ha-E-5 cell line had typical apoptotic response following AcMNPV infection, but QB-Ha-E-1 cell line, with the AcMNPV infection rate of 55.3%, appeared anti-apoptosis. Actinomycin D could induce apoptosis of the two cell lines at the concentration of 1.25 μg/mL. Therefore, the two cell lines can be used as ideal materials to study interactions between insect viruses and insect cells.

Key words: Helicoverpa armigera, embryonic cell line, baculovirus, infection, apoptosis