title: Cell confluency analysis on microcarriers by micro-flow imaging.
abstract: The productivity of cell culture-derived vaccines grown in anchorage-dependent animal cells is limited by bioreactor surface area. One way to increase the available surface area is by growing cells as monolayers on small spheres called microcarriers, which are approximately 100-250 μm in diameter. In order for microcarrier-based cell culture to be a success, it is important to understand the kinetics of cell growth on the microcarriers. Micro-flow imaging (MFI) is a simple and powerful technique that captures images and analyzes samples as they are drawn through a precision flow cell. In addition to providing size distribution and defect frequency data to compare microcarrier lots, MFI was used to generate hundreds of images to determine cell coverage and confluency on microcarriers. Same-day manual classification of these images provided upstream cell culture teams with actionable data that informed in-process decision making (e.g. time of infection). Additionally, an automated cell coverage algorithm was developed to increase the speed and throughput of the analyses.
authors.affiliation: Vaccine Analytical Development, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA, 19486, USA. christopher.farrell@merck.com.
authors.forename: Christopher J
authors.identifier: http://orcid.org/0000-0003-3506-6782
authors.initials: CJ
authors.lastname: Farrell
authors.affiliation: Eurofins Lancaster Laboratories Professional Scientific Services, Lancaster, PA, USA.
authors.forename: Stephanie M
authors.initials: SM
authors.lastname: Cicalese
authors.affiliation: Vaccine Drug Product Development, Merck & Co., Inc., West Point, PA, USA.
authors.forename: Harrison B
authors.initials: HB
authors.lastname: Davis
authors.affiliation: Applied Mathematics and Modeling, Merck & Co., Inc., Rahway, NJ, USA.
authors.forename: Belma
authors.initials: B
authors.lastname: Dogdas
authors.affiliation: Applied Mathematics and Modeling, Merck & Co., Inc., Rahway, NJ, USA.
authors.forename: Tosha
authors.initials: T
authors.lastname: Shah
authors.affiliation: Vaccine Analytical Development, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA, 19486, USA.
authors.forename: Tim
authors.initials: T
authors.lastname: Culp
authors.affiliation: Vaccine Analytical Development, Merck & Co., Inc., 770 Sumneytown Pike, West Point, PA, 19486, USA.
authors.forename: Van M
authors.initials: VM
authors.lastname: Hoang
keywords: Confluency; Mammalian cell culture; Micro-flow Imaging; Microcarriers