According to Lisa Bradbury, director, R&D cell therapy, Pall (www.pall.com), genomics methods are most applicable during cell-line optimization and expansion, but less useful during production. Since protein production is the objective, proteomics are the most useful.
“Genomics can tell you where DNA is located in the genome, and if it is being transcribed to RNA, but when you are talking about expressing foreign proteins the rate-limiting step is not RNA production but the ability to process that RNA into protein of interest.”
Through a process proteomics collaboration, Pall combines Ciphergen’s (www.ciphergen.com) SELDI ProteinChip® proteomics-profiling capability with Pall’s Biosepra line of separations products (acquired from Ciphergen in 2004). ProteinChip is a microarray product that interfaces directly with a SELDI mass spectrometer. SELDI mass spectrometry acts as a rapid, straightforward mass detector for proteins ideal for optimizing separation systems, says Pall.
At the time of the Biosepra acquisition, Pall announced plans to establish process proteomics service centers to help customers select and optimize sorbents and membranes for protein purification. It has since opened several centers, operating on a fee-for-service basis, where Pall scientists optimize protein separations on customer feedstock using Pall/Biosepra separations media through a variety of sorbent chemistries.
Services provided at the centers are suitable for expression optimization, purification development, and QA/QC through analysis of impurities. Pall claims that microscale methods and processes are scalable to pilot and manufacturing scale.
Invitrogen (www.invitrogen.com) has begun incorporating omics technologies into its PD-Direct™ bioprocess development services. PD-Direct operates from cell line selection through media development to scale-up for manufacturing. Invitrogen has invested “quite a lot of money and energy” into building PD-Direct into a continuation of the company’s discovery-stage proteomics and genomics customers, says Trent Carrier, Ph.D., director of business development for PD-Direct. “Our goal is to help these clients bridge from discovery through clinical stages and commercialization.”
PD-Direct builds on Invitrogen’s genomics and proteomics toolkits for discovery efforts, plus its Gibco subsidiary’s expertise in cell culture media development. “Connecting the pieces along the development path provides clients with consistent, integrated solutions,” Dr. Carrier says.
Programs like PD-Direct are causing Invitrogen to rethink how genomics and proteomics fit into the overall development scheme, particularly in cell-line development. Most process omics efforts to date, notes Dr. Carrier, have been based on cellular mechanisms. “You plate cells, see which genes are turning on and off, and manipulate or monitor those pathways relevant to cell viability.”
Invitrogen’s approach, which he calls “observation-based,” uses its Revolution™ technology to accelerate cellular genetic evolution into desirable phenotypes—for example high protein titers, faster growth, or longer productive culture life.
Invitrogen is working on a number of contracts using PD-Direct Revolution to improve existing production cell lines for products entering early clinical studies. Revolution is for proteins that are difficult to express, are not secreted, or are inhibitory to cells. “We’ve used Revolution more than a dozen times for these types of proteins, and improved productivity from 5 pg/cell/day to over 20 pg/cell/day,” says Dr. Carrier.
Incorporating omics technologies during development and manufacturing is an ongoing, evolving effort at Invitrogen, Dr. Carrier admits. “To be honest, we’re not exactly where we want to be in terms of having omics tools in place for process development. We’re still working on that synergy with the rest of Invitrogen.”