The cell culture techniques have allowed to study the behavior of cells outside of the living organism in artificial conditions which reproduce, as faithfully as possible, the microenvironment of the tissue or organ from which they derive. The experiments performed on cultured cells are defined in vitro to distinguish them from those in vivo that are executed on the living organism. The tissue culture and cell phones affect many areas of scientific research. Among the possible applications are: the study of the regulation of cell life and response to external stimuli under controlled conditions; the verification of the effect of various chemical compounds and drugs on specific cell types (eg,., tumor cells); the study of the use of cells for the generation of tissue in the test tube (eg., artificial skin); the synthesis of organic products on a large scale (eg,., therapeutic proteins). There have been numerous milestones in the history of the development of cell cultures and tissues.
The first experiment in tissue culture dates back to 1907, when Ross Harrison (1870-1959) of Yale University withdrew a small piece of tissue from the spinal cord of a frog embryo and laid him in a clot of sap. The observation of the tissue under a microscope for several days allowed Harrison to find out that the nerve cells were maintained viable in the medium used. A short time later, Alexis Carrel (1873-1944), Nobel Prize in 1912 for medicine and physiology and considered one of the pioneers in the history of the cell cultures, showed that they could keep the cells outside the body under sterile conditions . In the fifties Harry Eagle gave a major boost to this area of research by studying the necessary nutrients to the cells in culture. Proved fact that animal cells could grow in a cocktail of substances in the chemical composition defined in the presence of serum. Cell cultures have been and still are a very useful tool for the development of vaccines. In 1949 it was shown that the poliovirus could grow in cultures of human cells. The polio vaccine virus deactivated became one of the first commercial products of crops animals. Another milestone in the technology of the cell cultures was placed in 1975 with the development of a technique for the production of hybrid cells, including cells capable of producing antibodies, macromolecules that have an important value for both diagnostic for therapy.
The knowledge and techniques in the field of cell cultures accumulated over time allow us today to cultivate in the laboratory many cell types. From a small fragment of tissue is possible to isolate, through specific procedures, individual cells kept viable thanks to the contribution of nutrients provided by the culture medium. Thanks to the process of division, in culture the cells are able to replicate rise to new cells identical to the parent cell for a defined number of times. In addition, under the influence of appropriate stimuli, may undergo differentiation, namely the assumption of a specific shape and function. Because of this property it is possible today to propose cell cultures as a tool for regeneration of artificial tissues that can be used in the context of new therapeutic strategies. In appropriate experimental conditions the cells may undergo a transformation process that involves a series of changes at the expense of the nucleus and the cytoplasm, altering their normal properties and in some cases making them look like cancer cells.
