Decreasing the volume of media required to maintain cell viability not only reduces contamination of bioreactors from the upstream process, but may contribute to cost-containment measures in the biopharmaceutical industry. Based on our recent finding that dextran-containing nanocarriers increased CHO cell density up to 20 fold compared to its cellulose-containing microcarrier counterpart (manuscript submitted), we then investigated the possibility of reducing media volume to maintain cell viability, by utilizing the same dextran-based nanocarrier prepared from a self assembling nanoemulsion (SANE) method, and an adherent Chinese hamster ovary (CHO) cell culture line to evaluate media volume requirements. At the same 60 mL volume of media, cell viability after day 3 was 6 fold greater in CHO cells exposed to dextran-containing nanocarriers compared to cellulose-based microcarriers. When CHO cells were exposed to 60 mL of media containing dextran-based nanocarriers compared to 100 mL of media for cellulose-microcarriers, at day 6, cell density was up to 7 fold greater. Similarly, cell lysate protein concentrations at day 6 was nearly 3 fold greater for CHO cells exposed to dextran-containing nanocarriers compared to the cellulose-based microcarriers. Furthermore, nanocarriers had 59% greater glucose concentration, used as a measure of the polymer dextran and cellulose content levels in the nanocarriers and microcarriers, respectively. In conclusion, nanocarriers with increased numbers of dextran molecules, developed in these studies may be useful to further optimize media volume requirements for maximum culture growth.

Article D e x t r a n -c o n t a i n i n g n a n o c a r r i e r s significantly promote greater anchorage d e p e n d e n t c e l l g ro w t h a n d d e n s i t y compared to microcarriers Abstract Microcarriers containing cellulose-derived materials have been successfully applied to enhance the growth of anchorage-dependent cells maintained especially in bioreactors. By replacing microcarriers with nanocarriers containing dextran, we hypothesized that the density of the anchoragedependent cells would rise dramatically because the decreased particle size and associated enhancement in surface to volume ratios of nanoparticles contained within the nanoemulsion-based nanocarriers would increase the number of dextran molecules for the anchorage-dependent cells to attach to. Our studies utilized self-assembly nanoemulsions (SANE) formed by a modified phase inversion temperature (PIT) process to produce dextran oil and surfactant-containing nanocarriers having mean particle sizes of 26 nm compared to microcarriers which were greater than 6000 nm. Our results demonstrated that dextran-containing nanocarriers allowed up to 10 fold greater cell density,12% more media lactate concentration, 83% higher cell lysate protein and 59% greater glucose concentration, used as a measure of polymer levels in the nanocarriers compared to microcarriers. In conclusion, nanocarriers with increased numbers of dextran molecules, developed in these studies may be useful to further increase the production of anchorage-dependent animal cell-derived products or production of mass cell growth for other applications.Citation: E. Anton, et al. Dextran-containing nanocarriers significantly promote greater anchorage dependent cell growth and density compared to microcarriers.