Q&A with Select Cell Culture Experts
In this Q & A, three experts from both academia and industry discuss the types of cell culture they perform in their labs, technologies they use, and the challenges they face.
OUR EXPERTS:
Simin Zaidi,
Director of Operations,
Stamford Bioprocess Technologies
Santa Ana, California
Claudia Zylberberg, Ph.D.,
CEO/CSO
Akron Biotech
Boca Raton, Florida
Aparna Oruganty,
Ph.D. Candidate in Biomedical Sciences
University of Massachusetts Medical School
Worcester, Massachusetts
Q: What type(s) of cell culture lab do you perform, for what industry?
A: Simin Zaidi: Production of proof-of-concept proteins from transient and stable cell lines to support process development, characterization and validation for biopharmaceuticals and biologics. Our lab is experienced in GMP production using mammalian cells in batch, fed batch, and perfusion cultures, as well as GMP microbial fermentation. Stamford Bioprocess Technologies is a small, customer-focused company. Our cell culture facilities are part of a 5600-square-foot process development (non-GMP), production, and GMP facility.
Claudia Zylberberg: We have two scales of work, research grade and cGMP grade in cleanrooms. For research grade we perform several bioassays and stem cell culture for our raw material qualification. We also conduct custom bioassay development. At large scale we manufacture other products, such as cellular fibronectin from human fibroblast, in one facility dedicated to human products. We also perform bioassays that require cell culture.
Aparna Oruganty: I work in an academic lab at a university with about ten other people. My work involves human and mouse cell lines as well as primary mouse neuronal cultures.
Q: What were your biggest challenges in setting up and/or managing a cell culture laboratory?
A: Simin Zaidi: As more vendors entered the cell culture space and existing vendors redefined their offerings, we found that vendors we had used historically were discontinuing certain equipment on which we relied. So we were forced to identify new trustworthy suppliers in a short timeframe.
Claudia Zylberberg: Maintaining records of all cultures and logging production electronically would be a top priority. I am not aware of anything other than Excel. Having electronic tools to track cell culture stage, media changes, schedule activities like testing and splitting, will help cell culture technicians maintain cleaning schedules and records together with cell culture activities—similar to a compliance software package that keeps track of the different activities carried out with different cell lines.
Aparna Oruganty: Our biggest challenge is maintaining our various cultures without contamination.
Q: What specific measures do you take to avoid/mitigate contamination?
A: Simin Zaidi: We insist that all mammalian cell lines be mycoplasma negative and should have documentation to support their status. During lab setup, the process development lab biosafety cabinets were professionally tested and we ran test cultures to ensure that they were operating as expected. We use disposable equipment as much as possible. Not just for small-scale cell culture but for bench-scale and larger controlled bioreactors. When clients are planning proof-of-concept studies, it is essential that their material never be contaminated by endotoxin, other proteins,
or anything else that may lead them to the wrong conclusion about their product(s). There are many methods to removeendotoxin from a product; however, these are methods we have no plans to employ in our mammalian facility, as we minimize endotoxin contamination of the product from the outset. The way we see it is that endotoxin is an indicator of the level of contaminating microbial control in one’s process. There are a myriad of other toxins that can affect animal studies that are not measured, so the best practice is to avoid their introduction in the first place. Major decisions are being made at this stage, so we ensure integrity of our client’s products by utilizing single-use product contact materials and employ clean practices often comparable to the controls in GMP.
Claudia Zylberberg: We use our own line of cleaning and incubator products, the Cleansolutions spray, Cleansolutions Waterbath, and Cleansolutions Incubator CO2, which come with cleaning validation support. We have not encountered
contamination in the last six years, and many customers are committed to these products.
Aparna Oruganty: We follow a number of protocols to avoid contamination, above all being good laboratory practices. We employ separate incubators for primary cell culture and cell lines and an antibacterial liquid for the incubator water and water bath. Our lab extensively uses gloves and disposable pipettes, and we never pour media directly from the media bottle. Instead we use a pipette to aliquot media and other reagents. Finally, we use antibiotics in our cell culture media.
Q: What can vendors do better to improve your lab’s workflow?
A: Simin Zaidi: We would like to see more disposable products for microbial fermentation at larger scales. We are very happy with the direction more vendors are moving in regarding single-use formats. We hope to see a decrease in costs of those materials as they become more widely used. It would be great to see a Nova Bioprofile (cell culture metabolite analyzer) type analyzer that can use smaller sample volumes so that it can be used for small-volume high-throughput culture.
Claudia Zylberberg: Generate electronic records and tablet software for documentation, traceability, and eliminating paper in cleanrooms that can be a source of contamination.
Aparna Oruganty: Media bottles could be designed more ergonomically, so they can be opened using just one hand. This will be particularly useful in speeding up the process of culturing cells. Another great product would be a sentinel cell line that would capture contamination earlier than most cell lines, thus helping in preventing contamination of important cells.