|El Sayed, Galal - UNIV OF MISSOURI|
|Stiles, Brad - BASF AGRO RESEARCH|
Submitted to: In Vitro Cellular And Developmental Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 20, 2001
Publication Date: June 20, 2001
Citation: GOODMAN, C.L., MCINTOSH, A.H., EL SAYED, G.N., GRASELA, J.J., STILES, B. PRODUCTION OF SELECTED BACULOVIRUSES IN NEWLY ESTABLISHED LEPIDOPTERAN CELLLINES. IN VITRO CELLULAR AND DEVELOPMENTAL BIOLOGY. 2001. V. 37. P. 374-379. Interpretive Summary: Pest insects cause billions of dollars of damage to crops in the U.S. annually. The use of baculoviruses (insect-specific viruses) as biological control agents is an effective means of controlling pest insect populations. These biocontrol agents are environmentally friendly because of their ability to only infect specific insect species, in contrast to classical insecticides which generally have some degree of toxicity to people and non-target organisms. Therefore, any means by which the production of baculoviruses can be optimized and made more cost-effective will encourage their use instead of that of traditional insecticidal chemicals. One means by which baculoviruses can be produced is in insect cell lines (cells which are removed from insects and can replicate in culture). The use of cell lines is considered to be a more efficient means of generating baculoviruses than is their production in live insects, although new cell lines are needed in order to maximize this process. In our study, we screened 34 newly established cell lines for their ability to produce 5 baculoviruses which were infectious to different pest insects. We found that we could replicate these viruses in moderate to high amounts in at least one (often more) new cell line(s) for each virus. Thus, many of our newly established cell lines may be useful in baculovirus mass production schemes. This is an important advancement for the production of baculoviruses in insect cells, which brings us one step closer to being able to provide these biocontrol agents to growers for the control of specific agricultural pest insects.
Technical Abstract: One key to the in vitro mass production of baculoviruses is the development of insect cell lines capable of producing high levels of extracellular virus (ECV) and/or occlusion body (OB). For this study, 34 newly established cell lines from 10 lepidopteran species were screened for their ability to produce ECV and OB from a variety of baculoviruses. The selected baculoviruses included: the alfalfa looper virus (AcMNPV); the celery looper virus (AfMNPV); the velvetbean caterpillar virus (AgMNPV), the bollworm virus (HzSNPV), the diamondback moth virus (PxMNPV), and the beet armyworm virus (SeMNPV). ECV titers were determined using TCID50 assays, with the presence or absence of OBs being noted. For AcMNPV, 28 new cell lines were tested with 8 producing AcMNPV ECV titers of 1.1 to 47.3 x 10**6 TCID50/ml and 11 producing OBs. For AgMNPV, 6 new cell lines were tested, with all producing AgMNPV ECV titers of 3.5 to 62.3 x 10**6 TCID50/ml and generating OBs. For HzSNPV, 4 new cell lines were tested with 3 lines producing HzSNPV ECV titers of 1.4 to 5.0 x 10**6 TCID50/ml, but none generating OBs. For PxMNPV, 10 new cell lines were tested with 7 generating PxMNPV ECV titers of 4.7 to 232.6 x 10**6 TCID50/ml and 8 producing OBs. Lastly, using qualitative or semi-quantitative methods, homologous cell lines were tested for AfMNPV and SeMNPV production, all of which produced OBs. Overall, many of the cell lines tested were found to produce OBs and generate moderate to high levels of ECVs of one or more baculoviruses.