Profiling miRNAs of high, low and non-producing CHO cells during biphasic Fed-Batch cultivations reveal interesting targets for cell line engineering

ABSTRACT: Fed-batch cultivation of recombinant Chinese hamster ovary (CHO) cell lines is one of the most widely used production mode for commercial manufacturing of recombinant protein therapeutics. Furthermore, fed-batch cultivations are often conducted as biphasic processes where culture temperature is decreased to maximize volumetric product yields. However, it still remains to be elucidated which intracellular regulatory elements actually control the observed pro-productive phenotypes. Recently, several studies have revealed microRNAs (miRNAs) to be important molecular switches of cell phenotypes since single miRNAs are capable of regulating entire physiological pathways. In this study, we analyzed miRNA profiles of two different recombinant CHO cell lines (high and low producer), and compared them to a non-producing CHO DG44 host cell line during fed-batch cultivation at 37 versus 30 °C culture temperature. Taking advantage of next-generation sequencing combined with cluster, correlation and differential expression analyses, we could identify 89 different miRNAs, which might be interesting for CHO cell engineering. Functional validation experiments using 19 validated target miRNAs confirmed that these miRNAs indeed induced changes in process relevant phenotypes such as recombinant protein production, apoptosis, necrosis and proliferation. Furthermore, computational miRNA target prediction combined with functional clustering identified putative target genes and cellular pathways, which might be regulated by these miRNAs. Taken together, our study systematically identified novel target miRNAs during different phases and conditions of a biphasic fed-batch process and functionally evaluated their potential for host cell engineering.

ORGANISM(S): Cricetulus griseus

PROVIDER: GSE72945 | GEO | 2016/04/03

SECONDARY ACCESSION(S): PRJNA295392

REPOSITORIES: GEO