PUBLICATION Mammalian Cell Designers’ Laboratory

MISSION

Our mission is to engineer next-generation mammalian cell factories
for the production of complex biotherapeutics.
By integrating synthetic biology, genome engineering, and autonomous experimentation,
we aim to transform cell line development from empirical optimization into a predictive engineering discipline.

Journal Articles

Reduced apoptosis in Chinese hamster ovary cells via optimized CRISPR interference
Author
Kai Xiong*, Kim Fabiano Marquart*, Karen Julie la Cour Karottki*, Shangzhong Li, Isaac Shamie, Jae Seong Lee, Signe Gerling, Nan Cher Yeo, Alejandro Chavez, Gyun Min Lee, Nathan E Lewis‡, Helene Faustrup Kildegaard‡
Vol
116(7)
Page
1813-1819
Year
2019

Chinese hamster ovary (CHO) cells are widely used for biopharmaceutical protein production. One challenge limiting CHO cell productivity is apoptosis stemming from cellular stress during protein production. Here we applied CRISPR interference (CRISPRi) to downregulate the endogenous expression of apoptotic genes Bak, Bax, and Casp3 in CHO cells. In addition to reduced apoptosis, mitochondrial membrane integrity was improved and the caspase activity was reduced. Moreover, we optimized the CRISPRi system to enhance the gene repression efficiency in CHO cells by testing different repressor fusion types. An improved Cas9 repressor has been identified by applying C-terminal fusion of a bipartite repressor domain, KRAB-MeCP2, to nuclease-deficient Cas9. These results collectively demonstrate that CHO cells can be rescued from cell apoptosis by targeted gene repression using the CRISPRi system.