Metal binding compounds and their use in cell culture medium compositions

Abstract

The present invention is directed generally to metal binding compounds which may be added to cell culture media to replace factors required for cultivation of the cells (e.g. transferrin) which are of animal or human origin. More specifically, the invention is directed to metal binding compounds or complexes thereof comprising one or more transition element cations (such as ferrous or ferric ions), which are added to cell and tissue culture medium compositions. The metal binding compounds may be added to the media alone or may be first complexed with a transition metal ion. The invention is also directed to methods of use of such compositions, including, for example, methods for the cultivation of eukaryotic cells, particularly animal cells, in vitro. The invention also relates to compositions comprising such culture media and one or more cells, and to kits comprising one or more of the above-described compositions. The compositions of the present invention obviate the need for naturally derived metal-binding proteins, such as transferrin and ceruloplasmin, which may contain blood-borne pathogens.

Description

CROSS REFERENCE TO RELATED APPLICATION[0001]The present application claims the benefit of U.S. Provisional Application No. 60 / 151,055 filed Aug. 27, 1999, the contents of which are fully incorporated by reference herein.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The present invention is in the fields of cell biology and biochemistry. The invention relates generally to cell and tissue culture medium compositions comprising metal binding compounds and / or transition element complexes comprising the metal binding compounds, and the use of such compounds and complexes. More specifically, the invention relates to compositions for cell and tissue culture comprising one or more transition element cations in a complex with a metal binding compound.[0004]2. Related Art[0005]Cell culture media provide the nutrients necessary to maintain and grow cells in a controlled, artificial and in vitro environment. Characteristics and formulations of cell culture media vary depending...

AI Technical Summary

Benefits of technology

The present invention provides compounds that can deliver transition metals to cells in vitro by adding them to culture media. These compounds can replace natural animal-derived metal carriers like transferrin and support the growth of various types of cells. The compounds can be added to serum-free media and are preferably used in the absence of transferrin. The metal-binding compounds can interact with or bind to transition elements and facilitate their uptake by cells. The invention also includes methods for using the compounds in cell culture and kits for growing cells.

Problems solved by technology

Unfortunately, the use of serum or animal extracts in tissue culture applications has several drawbacks (Lambert, K. J. et al., In: Animal Cell Biotechnology, Vol 1, Spier, R. E. et al., Eds., Academic Press New York, pp.

In addition, supplements of animal or human origin may also be contaminated with adventitious agents (e.g., mycoplasma, viruses, and prions).

These agents can seriously undermine the health of the cultured cells when these contaminated supplements are used in cell culture media formulations.

Further, these agents may pose a health risk when substances produced in cultures contaminated with adventitious agents are used in cell therapy and other clinical applications.

The presence of serum in culture media can present additional difficulties.

The use of undefined components such as serum or animal extracts also prevents the true definition and elucidation of the nutritional and hormonal requirements of the cultured cells, thus eliminating the ability to study, in a controlled way, the effect of specific growth factors or nutrients on cell growth and differentiation in culture.

Moreover, undefined supplements prevent the researcher from studying aberrant growth and differentiation and specific disease-related changes in cultured cells.

Using cell culture media in the industrial production of biological substances, serum and animal extract supplementation of culture media can also complicate and increase the costs of the purification of the desired substances from the culture media due to the necessity of removing serum or extract proteins.

Such media (often called “basal media”), however, are usually seriously deficient in the nutrition, hormone, or biological response modifier content required by most animal cells.

For example, there is a risk that the culture medium and / or products purified from it may be immunogenic, particularly if the supplements are derived from an animal different from the source of the cells to be cultured.

This approach, however, runs the risks of introducing contaminants and adventitious pathogens into the culture medium (such as HIV, Creutzfeld Jakob agent, or hepatitis viruses from HSA preparations, or Bovine Spongiform Encephalopathy prion from BSA preparations), which can obviously negatively impact the use of such media in the preparation of animal and human therapeutics.

This search is complicated by the fact that the natural iron carriers are often derived from serum and thus are subject to the above-described limitations of serum supplementation.

Although these references disclose some metal carriers, the interpretation of the data is complicated by several experimental factors.

Unfortunately, many of these simple iron chelating compounds do not provide sufficient iron availability to, or uptake by, cultured cells.