Dec 17, 2005
The applications of cell and tissue cultures are increasing in a variety of fields. Now in combination with biotechnology, cell and tissue culture has become the most useful tool for advancements and improvement of life.
Earlier, plant tissue cultures were limited for propagation of ornamental plants or for the plants which are difficult to propagate in vivo. Recently tissue cultures of medicinal herbs are reported. A protocol for in vitro multiplication on mass scale for a medicinal herb, Ophiorrhiza munga has been established (Jose and Satheshkumar, 2004). The roots of this plant contain a anticancerous alkaloid, Camptothecin (CPT) used as a drug in the treatments for various cancers of colon, head, breast and bladder (Hsiang et.al.,1985). Camptothecin also possesses the activity against HIV and retroviruses (Priel et.al.,1991a, 1991b) and parasitic trypanosomes and Leishmania (Bodley and Shapiro,1995). The roots of this herb are also used in the treatments of snake bite (CSIR,1966,1998). Next by applying tissue engineering, developing this plant with higher levels of camptothecin is not a far away step. It has noticed that plants of Clerodendrum aculeatum produced in tissue cultures posses high degree of resistance against viruses in susceptible healthy plants (Srivastava et.al.,2004).
In combination with biotechnology, animal tissue cultures are opening a new window every day. Since the first report of antibodies of predefined specificity (Kohler and Milstein, 1975), developments have been made to reshape the antibodies. Reshaping of antibodies to reduce the immunogenicity while maintaining or improving the affinity of murine antibodies has been achieved (Wang et. al., 2004).
Production of various enzymes, proteins, vaccines, human skin etc. in animal tissue cultures were reported during 1980-1990.The most recent attraction for investigations are around human stem cells, which can be used in transplantations and cell replacements therapy that could treat many debilitating diseases such as coronary heart disease, diabetes, cancer and Parkinsonís disease (Lovell-Badge, 2001).
Stem cells possess ability of self-renovation and can reproduce indefinitely to form specialized cells of tissues and organs. Stem cells are present in many tissues of adults and are important in tissue repair homeostasis. Stem cells may have various differentiation potentials such as totipotent, producing entire organism, multipotent, capable of producing different cell types and unipotent, producing only single type of tissue. Recently it has been proposed that human embryonic stem cells could be utilized for therapeutic cloning.
Adult stem cells scattered in various body tissues are an alternate source. These cells dwell in various tissues and replace damaged or dead cells with new ones. Hence, hematopoietic stem cells from a healthy individual are utilized in allogenic bone marrow transplantation to rejuvenate a patientís blood system. This concept is called as Regenerative Medicine. The cultured stem cells may be utilized for cell based therapies, generation of transgenic animals and preservation of endangered animals. In near future, if the cell lines from stem cells of pancreas or liver and other organs get established, the production of these organs for transplantation therapies is possible. With the advancements in animal tissue cultures, these organs i.e. our body spare parts will be on display in hospitals, ready for replacements and that should not be a surprise.