Baculovirus vectors

Multi-gene Baculovirus Vectors and Chimeric Particle Production. . 190... 

Cells derived from the ovary of the fall army worm Spodopterafrugiperda are the most common used cell lines for heterologous protein production with a baculovirus vector (see Table l),but some authors have reported the use of a different cell line for VLP production, Trichoplusia ni HighFive cells (Invitrogen, San Diego, US) [24,41,50]. 

The production of VLPs with baculovirus infected insect cells is entering the phase of industrial application. Due to the complexity of the system a multitude of vector strategies have been developed, ranging from single to fifth-level baculovirus vectors, along with combinations between them. 

Bayovac CSF E2 (vaccine consisting Bayer of r classical swine fever virus E2 subunit antigen, produced using a baculovirus vector system)... 

Condreay JP, Witherspoon SM, Clay WC, Kost TA (1999), Transient and stable gene expression in mammalian cells transduced with a recombinant baculovirus vector, Proc. Natl Acad. Sci. USA 96 127-132. 

Despite being more critical for intracellular products, protease action may also occur in extracellular media. For example, in the expression of a baculovirus vector, which is a lytic system, proteases are often expressed and secreted during recombinant protein production, and the problem may assume a critical level. A similar problem occurs in serum-free culture systems. The absence of proteins such as albumin and macroglobulin reduces the protection against proteolysis. In these cases, addition of an antiproteolytic agent to the culture medium is recommended. 

Carbonell, L.F., Hodge, M.R., Tomalski, M.D. and Miller, L.K. (1988). Synthesis of a gene coding for an insect-specific scorpion neurotoxin and attempts to express it using baculovirus vectors. Gene, 73, 409—418. 

Figure 1. Helper-independent baculovirus vector (Autographa cattfomica nuclear polyhedrosis virus).

Luckow, V.A. (1991). Cloning and expression of heterologous genes in insect cells with baculovirus vectors. In Recombinant DNA Technology and Applications. A. Prokop, R.K.Bajpai, and C.Ho, eds. (New York McGraw-Hill), pp. 97 152. 

Expression of viral structural proteins in a heterologous system does not always lead to formation of the desired assembly intermediate or end product. This is particularly the case when the proteins are expressed in E. coli or when individual components are expressed separately in different cells. In these cases, the proteins are usually purified and then assembled in vitro. Alternatively, assembly is possible using whole cell lysates. For example, assembly of HSV-1 capsids, which requires a minimum of four structural proteins, was observed on mixing of lysates derived from insect cells infected with different baculovirus vectors (Newcomb et al, 1994). Similarly, reovirus cores, obtained from native virions, could be... 

There is a licensing agreement through Professor Summers University of Texas (baculovirus vector system). 

Choudary, P.V., Kamita, S.G. and Maeda, S. Expression of foreign genes in Bombyx mori larvae using baculovirus vectors. Methods Mol. Biol, 39, 243, 1995. 

Summers M, Smith G (1987) Manual of methods for baculovirus vector and insect cell culture... 

Insect and Mammalian Cell Cultures. Animal cell cultures are the systems with highest similarity to human cells with respect to the pattern and capacity of posttranslational modifications. However, their cultivation is more complicated and costly and usually yields lower product titers. Among the known systems, insect cells transformed by baculovirus vectors have reached a comparable popularity as Pichia among yeasts because they are considered to be more stress resistant, easier to handle, and more productive compared with mammalian systems and are thus frequently employed for high-throughput protein expression. The highest reported... 

Hellers M, Gunne H, Steiner H. Expression of post-translational processing of prececropin A using a baculovirus vector. Eur J Biochem 1991 199 435-439. 

Atkinson, A. E., Earley, F. G. P., Beadle, D. J., and King, L. A. (1990a) Expression and characterisation of the chick nicotinic acetylcholine receptor a-subunit in insect cells using a baculovirus vector. Eur. J. Biochem. 192, 451-458. 

Possee, R. D. (1986) Cell surface expression of influenza virus haemagglutinin in insect cells using a baculovirus vector. Virus Res. 5, 43-59. 

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