Engineering mammalian cell factories for improved recombinant monoclonal antibody production: lessons from nature?

Abstract

In this review we consider how cell specific recombinant monoclonal antibody (Mab) production by engineered mammalian cells can be improved. Whilst it is generally recognized that Mab production is limited post-transcriptionally at folding and assembly reactions, genetic engineering strategies based on overexpression of individual chaperones or foldases in mammalian cells have not reliably increased cell specific Mab production. Given that recent studies have established that chaperones and foldases themselves exist in a large multiprotein complex, which may coordinate the sequential processing of Mabs, we propose that global expansion of all components of the secretory pathway will likely be necessary to generically improve recombinant Mab production by mammalian cells. In this context, what can be learnt from nature? Important recent studies have delineated some of the main cellular pathways involved in the differentiation of B-cells into nature's own high level Mab producers, plasma cells. This is achieved by a dramatic re-programming of cellular function where the coordinated expansion of metabolic and secretory machinery precedes Ig production, then is maintained by induction of a key intracellular signaling pathway, the unfolded protein response (UPR). Here we review genetic engineering strategies to increase cell specific production rate and discuss whether manipulation of intracellular signaling systems such as the UPR will provide a novel means to engineer mammalian cells for high level recombinant Mab production.

Kinetic studies of recombinant rabies virus glycoprotein (RVGP) cDNA transcription and mRNA translation in Drosophila melanogaster S2 cell populations

“…At the transition from the exponential to the stationary cell culture phase cell growth slowed down and RVGP Considering optimizations for the synthesis of heterologous recombinant protein by genetically modified cell populations, the easiest approach of favouring the cell multiplication in view of obtaining high levels of recombinant cell product may not be always the indicated one. A rational approach would be to somehow drive the cell metabolism redirecting cell resources used for cell proliferation to the recombinant protein expression (Palomares et al 2004;Dinnis and James 2005).…”

Nanocell targeting using engineered bispecific antibodies

“…A qualitative Western blot confirmed that BsAbs were efficiently secreted and that the lower product yields were not due to retention in the endoplasmic reticulum via cellular mechanisms such as the unfolded protein response (results not shown). [54][55][56][57] Targeted binding Binding activity was maintained for both EGFR and LPS targets for all engineered BsAb formats ( Table 2; Fig. 2).…”

Comparison of Antibody Molecules Produced from Two Cell Lines with Contrasting Productivities and Aggregate Contents

“…LCs are critical for the proper folding of HCs in ER, and the amount of free LCs in culture media is related to its productivity. [27][28][29][30][31][32] Although the production of LCs is reportedly related to the quality (aggregate content) of mAb, 33,34) the analyses in these study were conducted under conditions in which the productivity was intentionally lowered. Because these conditions have little relevance to those in which therapeutic mAbs are actually produced, it is important to analyze the effects of LCs on quality under conditions in which the cell selection process is actually performed.…”