Reduction of the infectivity of baculovirus stocks frozen at ultra-low temperature in serum-free media: The role of lipid emulsions.

The infectivity of stocks of baculoviruses produced in serum-free media is sensitive to freezing at ultra-low temperatures. The objective of this work was to elucidate the causes of such sensitivity, using as a model the freezing of stocks of Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV), a baculovirus widely employed as biological insecticide. Titers of supernatants of cell cultures infected with AgMNPV in four different serum-free media supplemented with lipid emulsions were reduced by 50 to 90% after six months freezing.

Production of the Anticarsia gemmatalis multiple nucleopolyhedrovirus in serum-free suspension cultures of the saUFL-AG-286 cell line in stirred reactor and airlift reactor.

The velvetbean caterpillar, Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae), is one of the main plagues for soybean crops. Velvetbean caterpillar larvae are susceptible to be infected by occlusion bodies of the baculovirus Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV), a biological insecticide. The insect cell line saUFL-AG-286 produces very high yields of occlusion bodies of AgMNPV in suspension cultures done in the low-cost serum-free medium UNL-10 in shake-flasks.

Production of occlusion bodies of Anticarsia gemmatalis multiple nucleopolyhedrovirus in serum-free suspension cultures of the saUFL-AG-286 cell line: influence of infection conditions and statistical optimization.

The influence of the conditions of infection on the yield of occlusion bodies (OBs) of the Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV), produced in serum-free suspension cultures of saUFL-AG-286 cells, was investigated by two 2(2) full factorial experiments with centre point. Each experiment tested the effects of the initial cell density and the multiplicity of infection at two levels, in the four possible combinations of levels and conditions, plus a further combination with each condition set at the middle of its extreme levels. The yield of occlusion bodies proved to be sensitive to the modification of infection conditions.

Growth, metabolism and baculovirus production in suspension cultures of an Anticarsia gemmatalis cell line.

The UFL-AG-286 cell line, established from embryonic tissue of the lepidopteran insect Anticarsia gemmatalis, has been identified as a good candidate to be used as a cellular substrate in the development of a process for in vitro production of the Anticarsia gemmatalis multicapsid nucleopolyhedrovirus, a baculovirus widely used as bioinsecticide. In order to characterize the technological properties of this cell line and evaluate its feasibility to use it for the large-scale production of Anticarsia gemmatalis multicapsid nucleopolyhedrovirus, UFL-AG-286 cells were adapted to grow as agitated suspension cultures in spinner-flasks. Batch suspension cultures of adapted cells in serum-supplemented TC-100 medium grew with a doubling time of about 29 h and reached a maximum cell density higher than 3.