Novel strategy to reduce lactic acid production and control ph in animal cell culture

Abstract

The present disclosure provides a method for culturing cells in exogenous lactic acid. Certain aspects of the present disclosure include the production of recombinant proteins, such as antibodies and fragments thereof. Certain aspects of the present disclosure also relate to methods of controlling lactic acid production, pH stability and osmolality in cell culture.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application is a division of U.S. patent application Ser. No. 12 / 903,046, filed Oct. 12, 2010, now pending; which application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 61 / 250,798 filed Oct. 12, 2009, where these applications are incorporated herein by reference in their entirety.BACKGROUND[0002]1. Technical Field[0003]The present disclosure is related generally to methods for culturing animal cells in the presence of exogenous lactate.[0004]2. Description of the Related Art[0005]A number of successful methods have been developed for the commercial production of recombinant therapeutic proteins and other products using animal cell culture. The fed-batch approach is among the more popular methods, as it works well for current good manufacturing process (cGMP) operations and provides improved cell culture performance compared to the batch method. It involves minimally invasive operations and a...

AI Technical Summary

Benefits of technology

The present patent relates to methods for culturing cells with exogenous lactate to produce recombinant proteins. The methods involve controlling cell metabolism and maintaining pH stability and osmolality in animal cell cultures. By adding exogenous lactate to the cell, the production of lactic acid is reduced and the specific lactic acid production rate of the cell is reduced by at least 50%. The sufficient concentration of exogenous lactate can be about 5 to about 100 mM. The cell can also be adapted to the exogenous lactate before culturing. The methods do not require an external pH control to maintain optimum cell growth and viability. The cells can also be infected with a viral vector or used for gene therapy or vaccine production. The patent also describes a method for culturing cells in a fed-batch animal cell culture to prevent an excessive osmolality increase in the cell culture. Overall, the methods provide efficient ways for producing recombinant proteins in animal cells.

Problems solved by technology

When glucose is above the minimum required amount, it is not metabolized efficiently.

Inhibition of cell growth is often partly due to excessive increases in osmolality in pH-controlled bioreactors; this is a particular challenge for fed-batch processes where the extension of culture time can be accompanied by excessive lactic acid accumulation (Chu and Robinson, Curr Opin Biotechnol 12:180-1872001; Hu and Ozturk, Cell Culture Technology for Pharmaceutical and Cell-Based Therapies.

Simple methods, such as control of the culture at lower pH, have been implemented in manufacturing operations, but are often insufficient.

Furthermore, low pH levels may negatively impact the growth, viability, or productivity of the cells, as well as the quality of any product derived from or generated by the cells.

1995, 46:579-587) may be considered not robust enough for implementation in actual cGMP operations.

Low glucose levels may lead to glucose depletion, apoptosis, and premature cell death (Yeo et al., Biotechnol Lett.

These considerations make implementation less attractive.

1992, 11:311-322) and may also lead to lower growth rates or reduced effectiveness.

1999, 66:238-246) are often time consuming and have the potential for creating unstable cell lines in CHO cell cultures.

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