Cell culture is the extraction of cells from a living organism and growing it in an artificial environment similar to that of a natural environment. It is an essential lab procedure in a majority of experiments in a molecular biology lab.
The necessity of culturing cell arose due to the need for testing the biochemical conditions and constituents of an animal body which enables us to understand the molecular basis of the different systems and pathways that runs the body.
It is a necessary element of understanding disease pathology. Now, this requires a definite amount of good quality cells isolated from a desired human tissue or animal tissue which can be grown and cultured in vitro, with the help of lab equipment. Today, we are going to learn more about this cell culturing and its role in experiments.
Growing Cells in a Lab – What does it mean? (cell culture techniques)
Although, cell culturing started with the aim of understanding cell function and condition in the body, yet it developed into an essential feature in drug development and testing. So, any kind of therapeutic agents and drugs is first tested and developed using cell culture techniques.
For this, we use a vast number of cells that are cultured and maintained for generations to use it in the future. So cell culture isn’t just isolating and deriving cells alone, it includes culturing those cells in a viable medium which allows subsequent subculturing from time to time for generations and lastly preservation of these cultured cells.
Primarily, cancer cells and stem cells are used for culturing cells. Stem cells are the most utilized cell culture for understanding different cell conditions and functions, whereas cancer cells are ideal for drug development and treatment strategies.
A particular type of cells cultured to give rise to more numbers of that particular cell type is known as cell lines, and it is this cell lines, that is, cells of that particular type which is further cultured and preserved in the next batch of culturing.
The Procedure of Growing Cells
Isolating Cells: The process of growing cells starts with the isolation of a particular cell type from the desired tissue. For cancer cell lines, we take the desired tissue from cancer patients while for other cells, foetal tissue, or neonatal tissue is the ideal source.
The cells remain embedded in a matrix of cohesively arranged cells which need to be broken from each other with the help of proteolytic enzymes such as trypsin, collagenase, etc. along with a chelating agent like EDTA.
Cell agitation tears apart the tissue and we get a suspension of cells which is further isolated into individual cells through various techniques such as enzymatic treatment, antibody labeling, fluorescence cells sorter, and dye labeling.
Culturing the Isolated Cells
Culturing these cells in lab equipment such as cell culture plates and cell culture flasks is the actual step from which the cell culture procedure begins.
There are 2 ways of culturing cells in the laboratory for in vitro experiments. The first is a liquid medium culture called suspension culture done in cell culture flasks, and the second is a semi-solid medium of culturing done in cell culture plates.
The first instance of cell culturing started with a suspension culture of frog nerve cells in a simple salt solution done by Ross Harrison in Yale University back in 1907.
The technique has evolved over the years, and now, molecular biologists can use culture cells in more accurate conditions with a range of supplements such as blood, nutrients proteins, lipids, growth factors, hormones, enzymes, etc. which is added to the already nutrient-rich culture media. These cell-cultured flasks and plates need proper temperature and gases like oxygen and carbon dioxide to grow for which they are kept in an incubator.
After the proper incubation period of 24-48 hours of inadequate temperature, the cells multiply to form the next generations.
Preserving the Cell Culture
This new cultured cell, which has a good proportion of cells, can be directly used for experiments or they can be preserved for future use.
For long term cell culturing, preservation at a low temperature called cryopreservation is essential. For preservation, the cells are further treated with protective agents such as glycerol and DMSO and stored at –130°C.
Now any time in the near future, one can prepare a subculture from these preserved cells using the same process as mentioned above.
This is how the simple technique of cell culture works, enabling researchers to grow cells in the lab for laboratory use in their experiments.