Encyclopedia

Cell culture medium is the substrate in which cells are cultured. Depending on the cell type, the culture medium may be a gel (agar medium) or a liquid that provides a suitable environment for the cultured cells. It provides the cells with nutrients (energy and nitrogen sources), vitamins, minerals, salts and keeps osmotic pressure in physiologic ranges. Additionally, it dilutes metabolic waste products. Mammalian cells may require specific gas pressures of oxygen and carbon dioxide plus the presence of hormones to ensure optimal growth conditions.

Chimeric antibodies are made by humanizing non-human antibodies. Historically, animals were the single available source of antibodies after being exposed to an antigen. The resulting antibodies had traits of the host animals and triggered immune responses when administered to patients. Thus, such antibody drugs need to have human antibody traits while keeping antigen binding fragments of non-human antibodies. 

The Chinese Hamster (Cricetulus griseus) is a small rodent native to Mongolia and China. They weigh from 30 g to less than 50 g, with a body length of 8 to 13 cm with a long tail that distinguishes it from other hamsters. They are famous in life sciences because the very popular and widely used CHO cell lines were derived from Chinese Hamster Ovary cells.

A mammalian cell line derived from Chinese Hamster Ovary cells. They are widely used in mammalian cell cultures for recombinant protein expression due to their relative ease in handling and high protein yields. Moreover, as eukaryotic cells they allow the expression of more complex proteins with native post-translational modifications, which are not accessible via E. coli cell cultures. In addition, the use of CHO cells abolishes the widespread need for laboratory animals for antibody production.

CHO cell antibody production refers to the process of using CHO cells to produce large quantities of a specific antibody. This process typically involves genetic engineering of the CHO cells to express the gene encoding the antibody of interest, followed by cultivation of the cells under controlled conditions to promote growth and production of the antibody.

The complement system is an innate branch of the human immune system that is complementary to the adaptive immune system. The complement system does not rely on antibodies or specific cells but consists of various protein precursors, which, when activated by pathogens, lead to inflammatory responses and recruitment of phagocytes to remove intruders or damaged cells.