Home blood glucose biosensors: a commercial perspective

Twenty years on from a review in the first issue of this journal, this contribution revisits glucose sensing for diabetes with an emphasis on commercial developments in the home blood glucose testing market. Following a brief introduction to the needs of people with diabetes, the review considers defining technologies that have enabled the introduction of commercial products and then reviews the products themselves. Drawing heavily on the performance of actual instruments and publicly available information from the companies themselves, this work is designed to complement more conventional reviews based on papers published in scholarly journals. It focuses on the commercial reality today and the products that we are likely to see in the near future.     

Production of anchorage-dependent cells—problems and their possible solutions

In vitro cell culture has proven to be a valuable procedure for the study of cellular function as well as the production of veterinary and human vaccines. In recent years, interest in cell culture technology has grown due to the need for production of interferon, monoclonal antibodies, various hormones, and other cell-secreted products with potential medical uses. Many of these products have been successfully produced only be cells which require attachment to a surface in order to grow and function. This requirement places severe limitations on the economics and feasibility of large-scale culture. In response, a number of new technologies have been proposed and developed in attempts to increase the surface area available within a given culture volume, to increase the cell density per surface area, to decrease medium and serum requirements per unit of product, to increase product production by control of the cellular environment, and to automate the production process. Some of the techniques and described along with their ability to control the environment of cells in culture.     

Review article: Commercialization of whole‐plant systems for biomanufacturing of protein products: evolution and prospects

Technology for enabling plants to biomanufacture nonnative proteins in commercially significant quantities has been available for just over 20 years. During that time, the agricultural world has witnessed rapid commercialization and widespread adoption of transgenic crops enhanced for agronomic performance (herbicide‐tolerance, insect‐resistance), while plant‐made pharmaceuticals (PMPs) and plant‐made industrial products (PMIPs) have been limited to experimental and small‐scale commercial production. This difference in the rate of commercial implementation likely reflects the very different business‐development challenges associated with ‘product’ technologies compared with ‘enabling’ (‘platform’) technologies. However, considerable progress has been made in advancing and refining plant‐based production of proteins, both technologically and in regard to identifying optimal business prospects. This review summarizes these developments, contrasting today’s technologies and prospective applications with those of the industry’s formative years, and suggesting how the PM(I)P industry’s evolution has generated a very positive outlook for the ‘plant‐made’ paradigm.     

Plant cell culture and natural product synthesis: An academic dream or a commercial possibility?

Work with plant cell cultures has developed rapidly in recent years, progress being manifested particularly by the development of commercial process technology for the synthesis of selected natural products. The economics of operating a plant-cell culture process are, however, still questionable, and a great deal still needs to be done to strengthen the underlying science before the technology can be regarded as industrially commonplace. Nonetheless, the great versatility of plants as centres of chemical synthesis suggests that, with appropriate developments in cell culture technology, this area may have a significant role to play in the fine chemicals industry of the future.     

Transgenic animals and nutrition research

Transgenic animals are useful tools for the study of biological functions of proteins and secondary gene products synthesized by the action of protein catalysts. Research in nutrition and allied fields is benefiting from their use as models to contrast normal and altered metabolism. Although food, nutritional products, and ingredients from transgenic animals have not yet reached consumers, the technologies for their production are maturing and yielding exciting results in experimental and farm animals. Regulatory governmental bodies are already issuing guidelines and legislation in anticipation of the advent of these products and ingredients. This review summarizes available technology for the production of transgenic animals, discusses their scientific and commercial potential, and examines ancillary issues relevant to the field of nutrition.     

Crop improvement through tissue culture

Plant tissue culture comprises a set of in vitro techniques, methods and strategies that are part of the group of technologies called plant biotechnology. Tissue culture has been exploited to create genetic variability from which crop plants can be improved, to improve the state of health of the planted material and to increase the number of desirable germplasms available to the plant breeder. Tissue-culture protocols are available for most crop species, although continued optimization is still required for many crops, especially cereals and woody plants. Tissueculture techniques, in combination with molecular techniques, have been successfully used to incorporate specific traits through gene transfer. In vitro techniques for the culture of protoplasts, anthers, microspores, ovules and embryos have been used to create new genetic variation in the breeding lines, often via haploid production. Cell culture has also produced somaclonal and gametoclonal variants with crop-improvement potential. The culture of single cells and meristems can be effectively used to eradicate pathogens from planting material and thereby dramatically improve the yield of established cultivars. Large-scale micropropagation laboratories are providing millions of plants for the commercial ornamental market and the agricultural, clonally-propagated crop market. With selected laboratory material typically taking one or two decades to reach the commercial market through plant breeding, this technology can be expected to have an ever increasing impact on crop improvement as we approach the new millenium.D.C.W. Brown is with Agriculture and Agri-Food Canada, Central Experimental Farm, Plant Research Centre, Ottawa, Ontario, K1A 0C6, Canada. T.A. Thorpe is with the Plant Physiology Research Group, Department of Biological Sciences, University of Calgary, Calgary, Alberta, T2N 1N4, Canada     

Bioreactors for plant cells: hardware configuration and internal environment optimization as tools for wider commercialization

Mass production of value-added molecules (including native and heterologous therapeutic proteins and enzymes) by plant cell culture has been demonstrated as an efficient alternative to classical technologies [i.e. natural harvest and chemical (semi)synthesis]. Numerous proof-of-concept studies have demonstrated the feasibility of scaling up plant cell culture-based processes (most notably to produce paclitaxel) and several commercial processes have been established so far. The choice of a suitable bioreactor design (or modification of an existing commercially available reactor) and the optimization of its internal environment have been proven as powerful tools toward successful mass production of desired molecules. This review highlights recent progress (mostly in the last 5 years) in hardware configuration and optimization of bioreactor culture conditions for suspended plant cells.     

Implementation of advanced technologies in commercial monoclonal antibody production

Process advancements driven through innovations have been key factors that enabled successful commercialization of several human therapeutic antibodies in recent years. The production costs of these molecules are higher in comparison to traditional medicines. In order to lower the development and later manufacturing costs, recent advances in antibody production technologies target higher throughput processes with increased clinical and commercial economics. In this review, essential considerations and trends for commercial process development and optimization are described, followed by the challenges to obtain a high titer cell culture process and its subsequent impact on the purification process. One of these recent technical advances is the development and implementation of a disposable Q membrane adsorber as an alternative to a Q-packed-bed column in a flow-through mode. The scientific concept and principles underlining Q membrane technology and its application are also reviewed.     

Three‐dimensional cell culture model utilization in cancer stem cell research

Three‐dimensional (3D) cell culture models are becoming increasingly popular in contemporary cancer research and drug resistance studies. Recently, scientists have begun incorporating cancer stem cells (CSCs) into 3D models and modifying culture components in order to mimic in vivo conditions better. Currently, the global cell culture market is primarily focused on either 3D cancer cell cultures or stem cell cultures, with less focus on CSCs. This is evident in the low product availability officially indicated for 3D CSC model research. This review discusses the currently available commercial products for CSC 3D culture model research. Additionally, we discuss different culture media and components that result in higher levels of stem cell subpopulations while better recreating the tumor microenvironment. In summary, although progress has been made applying 3D technology to CSC research, this technology could be further utilized and a greater number of 3D kits dedicated specifically to CSCs should be implemented.     

Emerging protein delivery methods

The efficient and safe delivery of therapeutic proteins is the key to commercial success and, in some cases, the demonstration of efficacy in current and future biotechnology products. Numerous delivery technologies and companies have evolved over the past year. To critically evaluate the available options, each method must be assessed in terms of how easily it can be manufactured, impact on protein quality, bioavailability, and toxicity. Recent advances in depot delivery systems have, for the most part, overcome all of these obstacles except for complex and costly manufacturing. On the other hand, pulmonary delivery usually involves efficient manufacturing, but low protein bioavailability resulting in higher doses compared with injections. Although recent advances in transdermal and oral delivery have been significant, both of these delivery routes require logarithmic increases in bioavailability to make them viable candidates for commercialization. In the next few years, protein delivery for commercial products will probably be limited to injection devices, depot systems and pulmonary administration.     

The Biotechnological Potential of Thraustochytrids

Thraustochytrids are common marine microheterotrophs, taxonomically aligned with heterokont algae. Recent studies have shown that some thraustochytrid strains can be cultured to produce high biomass, containing substantial amounts of lipid rich in polyunsaturated fatty acid (PUFA). It is also evident that cell yield and PUFA production by some thraustochytrid strains can be varied by manipulation of physical and chemical parameters of the culture. At present, fish oils and cultured phototrophic microalgae are the main commercial sources of PUFA. The possible decline of commercial fish stocks and the relatively complex technology required to commercially produce microalgae have prompted research into possible alternative sources of PUFA. The culture of thraustochytrids and other PUFA-producing microheterotrophs is seen as one such alternative. Indeed, several thraustochytrid-based products are already on the market, and research into further applications is continuing. Many fish and microalgal oils currently available have relatively complex PUFA profiles, increasing the cost of preparation of high-purity PUFA oils. In contrast, some of the thraustochytrids examined to date have simpler PUFA profiles. If these or other strains can be grown in sufficient quantities and at an appropriate cost, the use of thraustochytrid-derived oils may decrease the high expense currently involved with producing high-purity microbial oils. As more is learned about the health and nutritional benefits of PUFA, demand for PUFA-rich products is expected to increase. Results to date suggest that thraustochytrids could form an important part in the supply of such products. Received February 17, 1999; accepted June 25, 1999     

Animal cell cultures: recent achievements and perspectives in the production of biopharmaceuticals

There has been a rapid increase in the number and demand for approved biopharmaceuticals produced from animal cell culture processes over the last few years. In part, this has been due to the efficacy of several humanized monoclonal antibodies that are required at large doses for therapeutic use. There have also been several identifiable advances in animal cell technology that has enabled efficient biomanufacture of these products. Gene vector systems allow high specific protein expression and some minimize the undesirable process of gene silencing that may occur in prolonged culture. Characterization of cellular metabolism and physiology has enabled the design of fed-batch and perfusion bioreactor processes that has allowed a significant improvement in product yield, some of which are now approaching 5 g/L. Many of these processes are now being designed in serum-free and animal-component-free media to ensure that products are not contaminated with the adventitious agents found in bovine serum. There are several areas that can be identified that could lead to further improvement in cell culture systems. This includes the down-regulation of apoptosis to enable prolonged cell survival under potentially adverse conditions. The characterization of the critical parameters of glycosylation should enable process control to reduce the heterogeneity of glycoforms so that production processes are consistent. Further improvement may also be made by the identification of glycoforms with enhanced biological activity to enhance clinical efficacy. The ability to produce the ever-increasing number of biopharmaceuticals by animal cell culture is dependent on sufficient bioreactor capacity in the industry. A recent shortfall in available worldwide culture capacity has encouraged commercial activity in contract manufacturing operations. However, some analysts indicate that this still may not be enough and that future manufacturing demand may exceed production capacity as the number of approved biotherapeutics increases.     

New aspects of natural products in drug discovery

During the past 15 years, most large pharmaceutical companies have decreased the screening of natural products for drug discovery in favor of synthetic compound libraries. Main reasons for this include the incompatibility of natural product libraries with high-throughput screening and the marginal improvement in core technologies for natural product screening in the late 1980s and early 1990 s. Recently, the development of new technologies has revolutionized the screening of natural products. Applying these technologies compensates for the inherent limitations of natural products and offers a unique opportunity to re-establish natural products as a major source for drug discovery. Examples of these new advances and technologies are described in this review.     

Immunosensors in medical diagnostics--major hurdles to commercial success.

In the last few years the format of commercial immunoassays has dramatically changed. Automated instruments running up to 180 samples per hour and dry strip or film immunochemistry products are now available. These changes have been precipitated by the need for immunoassays that require less time and skill to perform. To date, no immunosensor technology has been successfully commercialized although a few are purported to be on the brink of being released for sale. Here, B. Manning and T. Maley evaluate the major factors affecting the success of immunosensors.     

Biotechnological production and applications of phytases

Phytases decompose phytate, which is the primary storage form of phosphate in plants. More than 10 years ago, the first commercial phytase product became available on the market. It offered to help farmers reduce phosphorus excretion of monogastric animals by replacing inorganic phosphates by microbial phytase in the animal diet. Phytase application can reduce phosphorus excretion by up to 50%, a feat that would contribute significantly toward environmental protection. Furthermore, phytase supplementation leads to improved availability of minerals and trace elements. In addition to its major application in animal nutrition, phytase is also used for processing of human food. Research in this field focuses on better mineral absorption and technical improvement of food processing. All commercial phytase preparations contain microbial enzymes produced by fermentation. A wide variety of phytases were discovered and characterized in the last 10 years. Initial steps to produce phytase in transgenic plants were also undertaken. A crucial role for its commercial success relates to the formulation of the enzyme solution delivered from fermentation. For liquid enzyme products, a long shelf life is achieved by the addition of stabilizing agents. More comfortable for many customers is the use of dry enzyme preparations. Different formulation technologies are used to produce enzyme powders that retain enzyme activity, are stable in application, resistant against high temperatures, dust-free, and easy to handle.     

Biological safety considerations in the production of health care products from recombinant organisms

Safety considerations in the field of recombinant technology and rDNA production of health care products have been under discussion since the beginning of this technology in 1973 and will certainly go on. However no adverse effects, which could have been attributed to rDNA technology have been observed. On the other hand many life-saving and life-improving drugs have been on the market for many years to the benefit of many patients. New technologies and products thereof often provoke uncertainties about their impact on the environment or society. This article discusses some potential risks in the application of rDNA technology to drugs as well as some benefits for patients, society and environment.     

Rational and "irrational" design of proteins and their use in biotechnology

A familiar refrain within industrial circles is better, faster, and cheaper. Efforts to place this mantra into practice within the biotechnology industry has brought a focus on protein engineering as one method to create new products quickly and inexpensively. Typically, protein engineering has utilized either rational design or combinatorial methods, both of which have been explored and improved in recent years. Continued advancement in these two areas and their application to an increasing list of industrially and medically important processes mean that the number of "synthetic" proteins displacing old technologies is likely to grow at an amazing rate over the next few years. We discuss some of the technologies available for protein redesign and illustrate these with examples from the biocatalysis, biosensor, and therapeutic fields.     

高通量微型生物反应器的研究进展

近年来,哺乳动物细胞培养技术发展迅猛,基于此技术的生物制药行业更是异军突起。在激烈的生物药市场竞争中,缩短研发时间和降低研发成本是制胜的关键。与传统的生物反应器相比,高通量微型生物反应器具有操作简单、运行通量高、实验重复性好等优点,可大大缩短研发周期,降低人力、物力成本,因此成为了生物制药行业最新的研究热点之一。目前,已成功应用于生物药物研发的微型生物反应器有Simcell ^TM、Ambr 15 ^TM、Ambr 250 ^TM等,分别适用于工艺开发中的不同阶段。以上述三种微型生物反应器为例,介绍高通量微型反应器在哺乳动物细胞培养工艺开发中的研究现状及发展前景。     

Do novel cement-type biomaterials reveal ion reactivity that affects cell viability in vitro?

Calcium phosphate bioceramics have been studied as bone filler materials for years and have become a component of many commercial products. It is widely known that surface-reactive biomaterials may cause changes in the concentration of crucial ions in the surrounding environment, thereby affecting cell metabolism and viability. The aim of this study was to produce five cement-type biomaterials and characterize their phase composition using X-ray diffraction method, and porosity and pore size distribution using mercury intrusion porosimeter. We then evaluated ion interactions of the novel biomaterials with the surrounding environment (culture medium). A commercially available bone substitute, HydroSet? (Stryker®), was used as a reference. MTT and NRU cytotoxicity tests were performed to assess the effect of changes in the concentration of crucial ions (calcium, magnesium, phosphate) on osteoblast metabolism and viability in vitro. Our study clearly indicated that various biomaterials demonstrated different ion reactivity and consequently may cause changes in ion concentration in the local environment. Critically low or high values of calcium, magnesium, and phosphate concentrations in the medium exerted cytotoxic effects on the cultured cells. Moreover, we discovered that the chemical composition of the culture medium had a substantial influence on ion interactions with biomaterials.