Cell culture technology is also called cell cloning technology, and the formal term in biology is cell culture technology. Cell culture is an indispensable process for the whole bioengineering technology or one of the biological cloning technologies, and cell culture itself is a large-scale cloning of cells. Cell culture technology can transform a cell into a simple single cell or multi-cell with little differentiation after a large number of cultures, which is an essential link of cloning technology, and cell culture itself is cell cloning. Cell culture technology is an important and commonly used technology in cell biology research methods. Through cell culture, a large number of cells can be obtained to study cell signal transduction, cell anabolism, cell growth and proliferation.
First, animal cell culture
Among all in vitro cell cultures, animal cell cultures are the most difficult. The following are the special conditions it needs.
⑴ Serum: In vitro culture of animal cells often needs serum. The most commonly used is calf serum. Serum provides essential factors for growth, such as hormones, trace elements, minerals and fats. Here, serum is equal to the natural nutrient solution of animal cells cultured in vitro.
⑵ Support: Most animal cells have the habit of adhering to the wall. In vitro culture usually uses glass and plastic as supports.
⑶ Gas exchange: In the process of cell culture, the ratio of carbon dioxide and oxygen should be constantly adjusted to maintain the required gas conditions.
Second, plant cell culture
⑴ Illumination: Plant cells cultured in vitro do not require high illumination conditions, because the substances needed for cell growth are mainly supplied by the culture medium. However, light is not only related to photosynthesis, but also to cell differentiation. For example, photoperiod can regulate sexual cell differentiation and flowering, so light conditions are particularly important in the early plant cell culture process for the purpose of obtaining plants. The process of obtaining important substances (such as drugs) by in vitro culture of plant cells, most of which are suspended in a reactor.
⑵ Hormones: The division and growth of plant cells need the regulation of plant hormones, and auxin and mitogen which promote growth are the most basic hormones. The division, growth, differentiation and individual growth cycle of plant cells are regulated by corresponding hormones. Compared with animal cells, the principle of hormone demand of plant cells in vitro culture has been understood, and its application technology has been quite mature, and a set of culture medium has been established. At the same time, it solves the demand of plant cells for water, nutrition, hormones, osmotic pressure, pH and trace elements.
Thirdly, microbial cell culture.
Microorganisms are mostly single-celled organisms, and the living conditions in the field are relatively simple. Therefore, the conditions for artificial cultivation of microorganisms are much simpler than those of animal and plant cells. Among them, the cultivation of anaerobic microorganisms is more complicated than aerobic microorganisms, because strict anaerobic needs to maintain the concentration of non-oxygen inert gases such as carbon dioxide, while aerobic microorganisms only need to provide sterile oxygen through continuous stirring. The requirements of microorganisms on culture conditions are not as good as those of animal and plant cells, and corn steep liquor, peptone, wort and yeast extract become good natural culture media for microorganisms. For the nutritional requirements of some special microorganisms, they can be added on the basis of these natural media.