What factors affect the cell culture conditions?

Factors which affect cell culture conditions include: temperature, pH, CO2, and O2 levels. The temperature has a strong effect on the metabolism and function of cells. Temperature changes affect processes such as proliferation, cell adhesion, and protein expression. Most human and mammalian cell lines are incubated at 36-37°C. The optimum temperature for cell cultures is reliant on the body temperature of the species and the environment in which the cultured cells were isolated. pH is another important factor, as alterations in pH in the cell culture can induce changes in processes including metabolism, membrane potential, and cell growth. In order for there to be optimal cell growth, the culture should be kept at a stable pH. The pH for the majority of human and mammalian cell lines should remain between 7.2-7.4. CO2 levels are significant for cell cultures as they dissolve and react with water to form carbonic acid. It then subsequently interacts with the conjugate base to regulate stable pH throughout the buffering system. 4-10% CO2 is recommended for the majority of cell culture experiments. O2 levels are important in cell culture as a small alteration can change the levels of HIF-1a and HIF-2a, which influences which genes are expressed as well as cell behavior. Normal oxygen levels in tissue culture is approximately 20-21% oxygen (160 mmHg).