Performance Challenging Fetal Bovine Serum (FBS) and FBS Alternatives

Abstract

Growth performance testing in cell culture is an effective approach to making serum suitability and purchase decisions.[1] An independent commercial testing lab conducted two separate and sequential growth promotion studies to underscore the need for pre-purchase lot performance testing with: (1) FBS; and (2) FBS alternatives. Results from both studies are presented here to compare and contrast: • FBS lots to each other • FBS alternatives lots to each other • FBS alternatives lots to FBS FBS alternatives are included because they are often overlooked as a cost-effective substitute for FBS, providing, in many cases, equivalent performance. It is advisable to avoid preconceived notions con cern ing the quality or performance of a serum product without considering the culture system, culture con ditions, and the subject cells, which can all have a material impact on its performance in cell culture. Test – then decide. 1. FBS Performance Challenge Test article (TA) lot performance was evaluated with three different cell lines at four TA concentrations. Additionally, the impact of TA concentration used in the cell culture medium was examined. FBS end-users employ various methods for assessing TABLE 1. Test article key, FBS performance challenge. TA # Supplier Description Catalog # Lot # 1 VWR Seradigm FBS 89510-194 013B16 2 VWR Seradigm FBS 89510-194 074B17 3 Testing Lab Control FBS — — 4 VWR Seradigm FB Essence 10805-184 048B16 5 GE Hyclone FBS SH30071.02 AB10104797 6 GE Hyclone FBS SH30071.02 AB10095803 7 ThermoFisher Gibco FBS A3160501 1883391 8 ThermoFisher Gibco FBS A3160501 1876851 the quality of FBS in cell culture. One of the most effective approaches is low-density plating efficiency testing.[1, 2] Plating efficiency is an individual characteristic of each adherent cell line (adhered /plated × 100). At clonal seeding density, the cells are unable to adequately condition the medium and must depend heavily on the nutritional capacity of the culture medium. The experimental design used in these two plating efficiency studies is based upon protocols cited above.[1, 2] 1.1 Materials and Methods Plating efficiency performance testing was conducted by an independent commercial testing lab on randomly selected production lots of FBS from three vendors (VWR Seradigm, GE HyClone, and ThermoFisher Gibco); two lots from each vendor (Table 1). FBS lots were tested in triplicate at four concentrations: 10 %, 7.5 %, 5.0 %, and 2.5 %. The FBS control was the test lab’s in-house lot to which all three cell lines were adapted pre-assay. The FBS control lot was not identical to any of the TA lots. Additionally, one lot of VWR Seradigm FB Essence, an FBS alternative, was included for comparison with this FBS performance challenge. Three adherent-dependent cell types were obtained from ATCC: CCL-34 (MDCK), CCL-75 (WI-38), and CCL-61 (CHO-K1). MDCK and CHO-K1 are cell lines that can be passaged indefinitely. WI-38 is a well-characterized normal human cell with a finite lifespan of approximately 50 population doublings (not passages). All three cell lines have been used in vaccine production. Clonal cell-seeding levels are different for each cell line and were determined for this study by preliminary testing. Three cell-seeding levels were examined for each cell line to ensure that usable data was generated. The seeding level delivering the most information for the most test articles