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bioRxiv · 10.1101/2025.05.21.655407

New glucose-abstaining Chlorella algae doubles mammalian cell culture longevity, boosts performance and drops serum needs enabling scaled applications.

Abstract

Mammalian cell culture technologies are crucial for recombinant protein production, organoid generation, medical applications, and the generation of in vitro cultivated meat. However, they are limited by high costs, vascular O2 provision, and the resultant inhibition of 3D tissue formation. Effective media usage along with oxygenation and waste management to extend culture health and longevity are key to improving all three. Microalgae, utilizing organic or inorganic CO2, produce O2 from light which complements oxygen-consuming and CO2-respiring mammalian cells and tissue culture. However, common microalgal cultivation conditions differ in temperature and salinity from mammalian cell cultivation environments, making co-cultivation short-lived and challenging. We screened several different microalgae species to identify locally isolated Chlorella BDH-1 as candidate that has high growth rates in mammalian culture conditions while, unlike other Chlorella species, does not compete for glucose as an energy source. In mammalian cell co-culture, BDH1 reduces cellular waste products, stabilizes pH, doubles culture longevity, increases growth performance up to 80%, and reduces expensive and ethically challenging foetal bovine serum requirements. Chlorella BDH-1 was also non-inflammatory and tolerant of clinical antibiotics. Collectively, mammalian cell/BDH1 co-cultivation improves tissue culture health and reduces costs, paving the path for applications in the biotechnology and medical sectors.

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BibTeXRIS

Oey, M., Marx, U., Schirra, H. J., Curson, J. E. B., Amado, M., Ross, I. L., Sweet, M. J., Blaskovich, M., Parton, R. G., Hankamer, B., Lo, H.. 2025-05-24. New glucose-abstaining Chlorella algae doubles mammalian cell culture longevity, boosts performance and drops serum needs enabling scaled applications.. https://doi.org/10.1101/2025.05.21.655407

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