The use of animal products, such as bovine serum, in the manufacture of biologics is a common practice. The United States’ Code of Federal Regulations, part nine (9CFR), dictates mandatory testing for viruses. In the last few years, we have learned that certain viruses undetected in industry standard tests, like the 9CFR assay, can cause significant contamination of bovine products. Last year in Europe, new guidelines from the Committee for Veterinary Medicinal Products (CVMP), and draft guidelines from the Committee for Proprietary Medicinal Products (CPMP), were published to address testing requirements for bovine serum. The use of these European Guidelines for bovine serum testing broadens the ability to detect viral contamination…
Category: <span>Biologics Production</span>
The K562 cell line is a human myelogenous leukemic cell which has been used by several groups, including ours, as a vehicle for cell-based vaccines and immuno-gene therapies. The attractiveness of K562 cells is the ease with which they can be cultured, plus the fact that they express very low levels of MHC proteins. Low MHC expression facilitates the use of these cells in patients with different MHC backgrounds, and it may improve the in vivo survival of the cells by delaying immune rejection. Based largely on these properties, we have been developing the K562 cell line as a universal platform for expressing cytokines, tumor antigens, and other immuno-modulating proteins…
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…
Based on feedback received from a number of our recent conferences, cell culture media development remains one of the biggest challenges in the development of biological products. With more products reaching larger production scale and licensed production, it is becoming ever more important that we gain a better understanding of the media supply industry, and that we find ways to make media development more economical, reliable, and reproducible…
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…
Serine-threonine kinases of the Mitogen Activated Protein Kinase (MAPK) pathway represent potential drug targets for a wide range of diseases. As part of an effort to understand the biology of the pathways, several human serine-threonine MAPKs were produced. Optimization and modification of current methodologies used in the baculovirus expression system resulted in the generation of large amounts of active MAPKs. Compounds found to inhibit the MAPKs in vitro, subsequently showed activity in cell-based assays and animal models. The processes to be discussed were developed to yield large quantities of three active human serine-threonine MAPKs by the baculovirus expression system…
Globally, an estimated 36 million people are living with HIV, and some 20 million people have already died of AIDS. Today, there is still no HIV vaccine available. HIV virus-like particles are an attractive vaccine candidate due to their ability to induce both antibody and cytotoxic T-lymphocyte responses. In this article, we describe the development of a production process for an HIV particle vaccine, HIV-1 p55 (gag). The gag precursor protein (p55) is sufficient for assembly and cellular release of retrovirus-like particles. We expressed the p55 gag protein using the BEVS technology in Spodoptera frugiperda expresSF+ cells…