Tag: <span>recombinant proteins</span>

The insect cell/baculovirus expression system typically results in more rapid expression and higher concentrations of recombinant proteins than what can be achieved with other animal cell culture systems. The lack of complex glycosylation in the proteins produced by this system, however, limits its use in the commercial-scale production of therapeutics. Complex glycosylation is required in many cases for adequate protein activity and pharmokinetic characteristics. In contrast to the protein’s primary structure, which is encoded by the genetic material and is constant regardless of the host utilized, the extent of glycosylation is determined by the host, and by the protein itself. Even cells from different tissues of the same organism provide different glycosylation profiles. In addition, culture conditions and the cellular metabolic state can also influence protein glycosylation…

Baculovirus Expression Technology Biologics Production

Recombinant adeno-associated viral (rAAV) vectors are known to be efficient vehicles for gene transfer in animal models. The attractive feature of this vector system consists primarily of long-term gene expression with little or no associated toxicities following administration to a variety of tissues. Previous and ongoing clinical trials in humans demonstrate a very good overall safety profile, but problems persist due to the lack of any systematic method for normalizing doses administered to animals and humans. To date, most of the work involves AAV serotype 2 vectors, but vector systems based on other AAV serotypes continue to develop rapidly. Administered doses are usually based on titer, but the defective nature of AAV makes determining vector infectious units difficult. Titering methods based on vector genomes (using hybridization, real-time PCR, or spectrophotometry) are more reliable, but give no information as to the infectivity of the vector. Determining infectious titer is critical, as the ratio of infectious virions to vector genome-containing virions helps to determine the dose, potency, and strength of the vector preparation…

Viral Reference Materials Viral Vectors

The baculovirus expression vector system (BEVS) is one method utilized for the production of recombinant proteins, and typically works without significant difficulties. However, some proteins are produced in insoluble forms, and degradation can occur. This article will focus on this degradation issue, and present a method to stabilize a protease-sensitive protein that has been produced at the 40-liter scale…

Baculovirus Expression Technology Biologics Production

The baculovirus expression system promises to revolutionize the production of recombinant proteins for use as clinical products. The technology is robust, efficient, and low-cost when compared to other cell based systems. The technique may also present an advantage in producing safer products versus the equivalent materials made with mammalian cells. Proteins can be produced in insect cells without animal supplements such as fetal calf serum. In the current climate of concerns over Bovine Spongiform Encephalopathies, and bovine viral risks, this method offers a significant safety, as well as cost advantage, over other production methods…

Baculovirus Expression Technology Regulatory

Baculovirus expression technology, or BEVS, gained its first broad industry exposure in the early 1980s, primarily through the many papers published by students and post-doctoral fellows in Dr. Max Summers’ laboratory at Texas A&M University (College Station, Texas). This technology fostered popular appeal because of its simplicity and high protein expression capabilities. As more work was done, it became even more evident that this was a very rapid, and relatively inexpensive method for producing proteins. It was also postulated that BEVS would offer a valuable means of producing recombinant proteins for use in human therapy, especially since baculovirus was considered non-infectious to human cells. It was thought that any problems with post-translational modifications of the manufactured proteins could be worked out, and fully functional glycoproteins could be manufactured…

Baculovirus Expression Technology