BIOLOGY Volume 2 - A Guide to General Biology - 2004

12. MICROBIOLOGY AND BIOTECHNOLOGY

12.8. Culturing Viruses

The cultivation, or propagation, of Viruses is a more complex Procedure than growing Bacteria, because viruses grow and multiply only inside living Cells. While it is possible to infect a whole Organism, such as a plant or animal, modern practice relies wherever possible on Cell or tissue cultures (Fig. 12.11). Previously, certain viruses were cultivated in developing chicken embryos inside the egg. A similar procedure of growing viruses in the Amniotic Fluid surrounding a chick embryo was used in The production of mumps and Influenza Vaccines.

A cell culture is a suspension of cells in a liquid medium, whereas a tissue culture consists of small pieces of plant or animal organ in a liquid or solid medium. Plant cell cultures typically utilize Meristems—regions such as ROOT or SHOOT tips where cells are actively dividing. The material can be taken from an infected plant or the culture can be inoculated with an appropriate virus. Animal Cell Cultures are generally established by growing isolated cells as a single layer On the surface of a Glass container (a monolayer culture). Poliovirus was first propagated in such a culture derived from monkey Kidney. Additionally, human lung, amnion, and Cancer cells have been used to establish tissue cultures.

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Fig. 12.11. Cell cultures for virus propagation, incubated in a sterile Temperature-controlled room.