Storage Preservation and Retrieval of Cultures, Neuroblastoma cells, Totipotent, Multipotent, Tumour cells, Cell line

	Storage, Preservation and Retrieval of Cultures Many types of animal cells are capable of growing in vitro, e.g., tumour cells, pigmented melanoma cells, neuroblastoma cells, etc. Based on the purpose of the experiment, a continuous (immortal) cell line can be developed from cultured tissues. Healthy animal tissues capable of dividing, are cultured on artifical nutrient media that proliferate and differentiate into a heterogeneous mixture of different types of cells
On the basis of the growth responses, culture cells may be classified as follows: Precursor or Master Cells or Stem Cells These have the ability to proliferate. But they do not differentiate until the proper conditions for induction are applied in the medium. This facilitates some or all cells to mature to differentiated cells. These are totipotent cells (multipotent or pluripotent) capable of differentiating into different types of cells
Undifferentiated but Committed Cells Committed precursor cells have only limited life and renew only under stress conditions. Test Tube Cultures It is a cheap technique and can be used for preparing a large number of cultures which can be placed in stationary racks or roller drums. This technique has poor optical property for microscopy. There is a high risk of contamination and also quantitation is very difficult.