In this interview, News-Medical talks to Dr. Lin Yutao, head of project management at Sino Biological, about the work she does and how Sino provides quick and efficient recombinant CRO services.
Could you provide a brief overview of Sino Biological？
Sino Biological was founded in 2007 and is a leading manufacturer of biological research reagents, offering a comprehensive set of premium quality recombinant proteins, elite antibodies, genes, ELISA Kits and other products. All reagents are developed and produced in-house.
The company also offers superior and integrated CRO services, including recombinant protein production services, antibody production & development services and bioanalysis services.
Powered by its in-house developed technology platforms and proprietary reagents, Sino Biological has rapidly grown into one of the largest protein vendors worldwide. During the past ten years, the company has successfully developed over 6,000 catalog protein products, and completed thousands of custom protein & antibody development and production projects.
Sino Biological, Inc.
Video Credit: Sino Biological
Can you explain what recombinant antibodies are?
Recombinant antibodies are monoclonal antibodies produced rapidly by recombinant DNA technology. Owing to their high specificity, sensitivity and reproducibility, recombinant antibodies are widely used in human therapeutics, diagnostics and a wide range of research applications.
In addition to full-length formats, recombinant antibodies can also be produced in different formats, including chimeric antibodies, bispecific antibodies and smaller antigen-binding fragments, such as fragment antigen binding and single chain fragment variable as well as single domain antibodies.
In addition, they can be generated in multiple expression systems, including bacteria, insect cells, yeast and mammalian cells.
Recombinant antibodies can be produced in mammalian systems using either transient or stable expression approaches. With the help of an efficient transient transfection platform, starting from antibody gene sequences, one could make sufficient quantities of monoclonal antibodies at high throughput in just a few weeks. In just a few weeks, 10-100 grams of high purity antibodies can be produced.
The human embryonic kidney (HEK) 293 cell lines have been widely used for transient protein expression due to the fact that expression vector introduction into these cells is highly efficient and results in significant yields of high-quality antibodies.
Can you describe the advantages of recombinant antibody manufacturing?
A recombinant antibody is a type of monoclonal antibody that is generated in vitro from a synthetic gene without the need for animal immunization or cell culture. The production involves in vitro genetic manipulation.
After cloning the antibody gene into an expression vector, this vector is subsequently introduced into an appropriate host cell line for antibody expression. Mammalian cell lines are most commonly used for recombinant antibody production given their high yields and accurate reproduction of antibody bioactivity, although cell lines of bacterial, yeast or insect origin are also suitable.
Recombinant antibodies can be cloned from any species of antibody-producing animals. Once the sequence is cloned, it is possible to modify it for enhanced or altered function – this is one of the major advantages of recombinant antibodies.
For example, Fc fragments from a species can be exchanged with another species to produce a chimeric antibody, and the variable chain on the Fab fragment can be mutated to alter binding specificity or affinity. Mutation of cloned antibodies is an alternate way to obtain the desired specificities, which can be implemented, if needed, for diagnostic and therapeutic applications.
In addition to the above advantages of ease and rapid engineering, recombinant antibodies have several advantages as compared to hybridoma-based systems for producing monoclonal antibodies.
The first is the increased reliability and reproducibility and a guaranteed long-term supply. The sequence of a recombinant antibody gene is known and fully characterized, making the resulting antibody product more reliable and more reproducible.
The second advantage of recombinant antibodies over hybridoma-based monoclonal antibodies is the fast production and diversity of the resulting produced antibodies. Recombinant technology decreases antibody production time to just a few weeks in most cases.
Finally, unlike traditional methods for antibody production, recombinant approaches avoid the need to use animals.
What can the use of a baculovirus-insect cell system provide that other cell systems cannot?
Insect cells are versatile expression hosts for a range of recombinant proteins. The accurate three-dimensional protein folding capability and relatively high culture density of insect cells resulting in considerable final yields make them excellent choices for the expression of complicated intracellular protein and virus proteins.
In addition, proteins that would normally be toxic to mammalian cells may be manufactured in insect cells. They may also be used for the manufacture of therapeutic recombinant antibodies or proteins.
In 2007, Cervarix, an HPV vaccine produced by an insect cell line in the format of virus-like particles (VLPs) was approved for human use.
Besides potentials in therapeutic and vaccine development, highly active proteins produced in insect cells are widely used in a variety of disciplines in biophysics and biochemistry for structure elucidation, drug design, assay establishment and diagnostic reagent development. Sino Biological employs insect cells extensively for recombinant protein product development and contract research projects.
Can you explain how Sino Biological is improving its research and development capabilities and what advantages this confers to the consumer?
Sino Biological’s core strength is its in-house developed mammalian cell culture and recombinant expression platforms. The platforms employ several proprietary reagents that are specially optimized to enhance the expression level of recombinant antibodies in HEK293 and CHO mammalian cells.
Sino’s proprietary high-density cell culture technology, combined with proprietary transfection reagents and medium formulations, and high-efficiency expression vectors, maximize the cells' longevity and increase the expression success rate, thereby saving clients considerable costs.
Sino Biological offers a variety of different packages for customers who need antibody expression services depending upon their specific requirements. High-throughput gene to antibody production service offers clients a rapid and cost-effective solution to quickly express a large number of antibodies at a small scale.
The service utilizes our expertise in high-throughput (HTP) gene synthesis, vector construction and optimized transient antibody expression technology to manufacture high-quality recombinant antibodies with high purity and low endotoxin levels. For larger-scale production requirements, Sino’s production capacity is considerable, via the use of over 80 bioreactors ranging from 2 L to 1500 L.
About Sino Biological & Dr. Lin
Sino Biological is an international reagent supplier and service provider. The company specializes in recombinant protein production and antibody development. All of Sino Biological's products are independently developed and produced, including recombinant proteins, antibodies and cDNA clones.
Sino Biological is the researchers' one-stop technical services shop for the advanced technology platforms they need to make advancements. In addition, Sino Biological offer pharmaceutical companies and biotechnology firms pre-clinical production technology services for hundreds of monoclonal antibody drug candidates.
Dr. Lin is the head of customer service and project management at Sino Biological.