When the editors of BPI asked us at BPSA to put together a content-rich article on single-use issues, we were happy to do so. Our challenge was how to bring in multiple viewpoints about the growing business of single-use that would be a “quick read” for the BPI audience. The answer: an expert colloquy. Represented here are several of the most qualified industry spokespersons in single-use — all are members of BPSA and speak as directors of the alliance. Their message: Single-use adoption is growing. BPSA has enabled significant educational initiatives responding to many technical concerns with plastic-based systems. And there is still much to be done as the end users of single-use systems begin to assay how to implement these innovative, flexible manufacturing platforms for drug and vaccine production. It’s been said that the transition between old and new is never elegant or seamless. But in the case of single-use, BPSA serves to smooth that transition with help from the experts that populate our allianc...
Every bioprocess begins with an expression system, and every expression system begins with DNA transfection. Derived from transformation and infection, the word paradoxically has come to be applied mainly to nonviral methods of genetically engineering cells; viral-vector–mediated DNA transfer is often called transduction . There are chemical, particulate, physical/mechanical, and viral means of getting new genetic material into a cell, and that DNA may take a number of different forms. Even the cloning method (pictured right) using a microscopic needle to inject a new cellular nucleus can be considered a form of transfection. Short-lived pores can be opened up in the outer membranes of animal cells for uptake of genetic vectors such as supercoiled DNA plasmids or an artificial chromosomes. Calcium phosphate can be used to facilitate the movement of DNA across cellular membranes, as can cationic liposomes. Electroporation increases membrane permeability through the application of an electrical field, ...
Since its inception 35 years ago, the biennial meeting of the European Society for Animal Cell Technology (ESACT) has built on a tradition of combining basic science and applications into industrial biotechnology to become the international reference event in its subject matter. Every other year, this gathering of academics and industry professionals features a famously exciting social program and an extensive vendor/supplier exhibition specific to animal cell technology. ESACT meetings are much-anticipated international venues for information exchange, inspiration, networking, and partnership. In 2013, the 23rd meeting in the series will take place at the Congress Centre of Lille (Lille Grand Palais) in France. In the 19th century, that city was an industrial power thriving in metalwork, chemistry, and textile manufacturing. Today it represents the fourth-largest French metropolitan area, an artistic and historic city as well as an important center for business and higher education — and consequently, re...
A bispecific antibody can bind two different antigens. Immunoglobulin G (IgG) type antibodies have two binding sites with different variable regions. An IgG variable region is made up of a variable light-chain sequence (VL) and a variable heavy-chain sequence (VH). The light chains (LCs) of common LC antibodies are identical for both variable regions, leaving the heavy chain (HC) for generating different specificities. Thus, recombinant host cells for production of common LC bispecific antibodies carry genes for both HCs, with the different specificities (A and B), along with one LC gene. A, B, and the light chains are expressed independently in those host cells, which then assemble them into three IgG types — AA, AB, and BB — for secretion into a culture environment. By purely random assembly, the three types should be produced in a ratio of 1:2:1 (AA, AB, and BB; AB and BA are equivalent). Purity of AB with respect to AA and BB thus would be only 50%. PRODUCT FOCUS: BISPECIFIC ANTIBODIES PROCESS FOCUS:
Monoclonal antibodies (MAbs) are an important class of biopharmaceuticals and are widely used to treat a variety of diseases such as cardiovascular diseases, cancer, and blood disorders. Antibodies are very complex proteins that show a high degree of microheterogeneities, including charge-, hydrophobicity- and size-related variances ( 1 ). Such variants can arise during any stage in a manufacturing process or storage as a result of enzymatic or nonenzymatic processes ( 2 ). Particular antibody variants that may affect the in vitro and in vivo properties of a molecule must be identified and minimized in a final product. Hence the analysis and understanding of microheterogeneity of a final product is a key challenge during development and manufacturing. Frequently observed posttranslational modifications known to form acidic antibody variants are deamidation of asparagine residues, sialylation, and N-terminal pyroglutamate formation ( 3 ). C-terminal lysine residues and oxidation of specific amino acid resi...
Virus filters are used in biomanufacturing to ensure the safety of biopharmaceutical drug products. As part of filter implementation, manufacturers are required to validate that the filtration process can indeed remove virus. Validations are typically performed at contract testing organizations (CTOs) that are “equipped for virological work and performed by staff with virological expertise in conjunction with production personnel involved in designing and preparing a scaled-down version of the purification process” ( 1 ). Virus removal capability of a filtration process is evaluated by a virus challenge or virus spiking study using a qualified scaled-down model of the filtration process. A scaled-down model is used because the need for large volumes of virus and drug product make the cost of conducting large-scale filter testing impractical. This scaled-down model uses the same membrane and operating conditions (pressures and flows) as are in the manufacturing process. Ideally, virus is spiked into a repr...
Physicians at Weill Cornell Medical College (WCMC) and biomedical engineers at Cornell University have succeeded in building living facsimiles of human ears. They believe that their bioengineering method will finally achieve the goal of providing normal-appearing new ears to children born with a congenital ear deformity. The researchers used three-dimensional (3D) printing and injectable gels made of living cells. Over a three-month period, the ears steadily grew cartilage to replace the collagen used in molding them. The study’s colead-author is Dr. Jason Spector (director of the Laboratory for Bioregenerative Medicine and Surgery, LBMS; associate professor of plastic surgery at WCMC; and adjunct associate professor in biomedical engineering department at Cornell University). He says, “A bioengineered ear replacement like this would also help individuals who have lost part or all of their external ear in an accident or from cancer.” Current replacement ears have Styrofoam-like consistency; sometimes, sur...