Plant protein hydrolysates support CHO-320 cells proliferation and recombinant IFN-γ production in suspension and inside microcarriers in protein-free media

Abstract

We have recently developed a protein-free medium (PFS) able to support the growth of Chinese hamster ovary (CHO) cells in suspension. Upon further supplementation with some plant protein hydrolysates, medium performances reached what could be observed in serum-containing media [Burteau et al. In Vitro Cell. Dev. Biol.-Anim. 39 (2003) 291]. Now, we describe the use of rice and wheat protein hydrolysates, as non-nutritional additives to the culture medium to support productivity and cell growth in suspension or in microcarriers. When CHO-320 cells secreting recombinant interferon-gamma (IFN-c) were cultivated in suspension in a bioreactor with our PFS supplemented with wheat hydrolysates, the maximum cell density increased by 25% and the IFN-c secretion by 60% compared to the control PFS. A small-scale perfusion system consisting of CHO-320 cells growing on and inside fibrous microcarriers under discontinuous operation was first developed. Under these conditions, rice protein hydrolysates stimulated recombinant IFN-c secretion by 30% compared to the control PFS. At the bioreactorscale, similar results were obtained but when compared to shake-flasks studies, nutrients, oxygen or toxic by-products gradients inside the microcarriers seemed to be the main limitation of the system. An increase of the perfusion rate to maintain glucose concentration over 5.5 mM and dissolved oxygen (DO) at 60% was able to stimulate the production of IFN-c to a level of 6.6 lg h À1 g À1 of microcarriers after 160 h when a cellular density of about 4 · 10 8 cell g À1 of carriers was reached.Abbreviations: AU -arbitrary units; CHO -Chinese hamster ovary; DO -dissolved oxygen; LDH -lactate deshydrogenase; IFN-c -interferon-gamma; PFA -protein-free medium for adhesion; PFS -protein-free medium for suspension; RP -rice protein hydrolysates; WP -wheat protein hydrolysates.

Combination of yeast hydrolysates to improve CHO cell growth and IgG production

“…Metabolic flux analyses showed that a peptone obtained from an animal source promoted the entry of pyruvate to TCA cycle (Bonarius et al 1996). Other studies underlined that peptones improved cell growth without increasing carbon source consumption and lactate production (Ballez et al 2004;Chun et al 2007), while ammonia production was slightly increased (Burteau et al 2003). Moreover, some authors underlined the potential use of lactate as a source of carbon after glucose depletion, triggered by plant hydrolysates (Burteau et al 2003).…”

Chickpea protein hydrolysate as a substitute for serum in cell culture

“…In order to address these concerns and limitations, serum-free and low-serum culture media have been developed. Some of these media include natural extracts that may be of animal origin, while others have a well defined composition (Ballez et al 2004;Burteau et al 2003;Schlaeger 1996;Taylor et al 1972a;Taylor et al 1972b). Arguably, media with a well defined composition and free of any serum or natural extract are the best choice for culturing cells, specially for research purposes, but these media are expensive and their use is not widespread.…”

Metabolic design of macroscopic bioreaction models: application to Chinese hamster ovary cells

“…The cell line is the CHO-320 line (see [1]) and the cells are cultivated in a serum-free medium: CHO-BDM S2.2. This medium contains basal defined medium (BDM), 0.1% pluronic F68 and a solution of ITS-S (1%).…”