Towards a widespread adoption of metabolic modeling tools in biopharmaceutical industry: a process systems biology engineering perspective.

In biotechnology, the emergence of high-throughput technologies challenges the interpretation of large datasets. One way to identify meaningful outcomes impacting process and product attributes from large datasets is using systems biology tools such as metabolic models. However, these tools are still not fully exploited for this purpose in industrial context due to gaps in our knowledge and technical limitations.

High-yield production of recombinant CRM197, a non-toxic mutant of diphtheria toxin, in the periplasm of Escherichia coli.

A high cell density fed-batch process was developed for production of recombinant CRM197, a non-toxic mutant of diphtheria toxin widely used as a carrier in polysaccharide-protein conjugate vaccines. Fully soluble recombinant CRM197 was obtained in high yields and with an authentic N-terminus, by targeting the protein to the periplasm of Escherichia coli using the Signal Recognition Particle (SRP)-dependent signal sequence of FlgI. Response Surface Methodology (RSM) was used to optimize the set-points of key process parameters (pH and feed rate at induction).

Validation of an enzyme-linked immunosorbent assay for the quantification of human IgG directed against the repeat region of the circumsporozoite protein of the parasite Plasmodium falciparum.

Background: Several pre-erythrocytic malaria vaccines based on the circumsporozoite protein (CSP) antigen of Plasmodium falciparum are in clinical development. Vaccine immunogenicity is commonly evaluated by the determination of anti-CSP antibody levels using IgG-based assays, but no standard assay is available to allow comparison of the different vaccines.

Methods: The validation of an anti-CSP repeat region enzyme-linked immunosorbent assay (ELISA) is described.