About Us

The Caltech Protein Expression Center (PEC) has been established since 1996, serving as a core facility to provide recombinant protein expression and purification for Caltech and external researchers. The center provides heterologous expression of recombinant proteins using E. coli, insect cells (Baculovirus) and mammalian cells (HEK293, CHO).

The majority of proteins produced in the mammalian HEK293 transient expression system are active human antiviral (anti HIV) antibodies and engineered antibody derivatives and viral glycoproteins (Engineering Immunity projects, Pamela Bjorkman).

The center has evolved over the last six years to provide additional capabilities that more fit the description of a Biotechnology center. In this context we have added to our program the generation of stably expressing HEK293 and CHO cell lines having the advantage over transient expression that the need to repeatedly prepare DNA for transfection becomes obsolete and that after only a single initial transfection followed by stable clone selection protein expression can be simply done by growing the given cell lines and harvesting the expressed proteins. This approach is widely used in the biotech industry but it is not trivial to derive cell lines. We consider our ability a big step forward since we can offer Caltech and outside scientists a serious capacity to produce large and consistent amounts of otherwise difficult to express proteins. We have furthermore developed our high throughput expression and optimization platform using robotic multiwell-plate based cell dispensing and transfection methods. We continue to provide support in the experimental design and execution for Surface Plasmon Resonance (SPR) based measurements of protein-protein interactions or generally of bio-molecular interaction studies using the Biacore T200 instrument. The interest and use of these instruments has become a valued asset in the Caltech research community.