In the research process of expanding the therapeutic uses of mesenchymal stem cells, they are grown in laboratories or grown using medication to stimulate new cell growth within the human body. In mesenchymal stem cell therapy, most of the cells are extracted from the adult patient's bone marrow  Mesenchymal stem cells can be obtained via a procedure called bone marrow aspiration. A needle is inserted into the back of the patients hip bone and cells are removed to be grown under controlled in vitro conditions in a lab. Over a course of two or three weeks, the cells will multiply and differentiate into specialized cells. The number of fully differentiated cells and their phenotype can be influenced in three ways. The first one is by varying the initial seed density in the culture medium. The second is by changing the conditions of the medium. The third is by the addition of additives such as proteins or growth hormones to the culture medium to promote growth. The mature cells are then harvested and injected back into the patient through local delivery or systemic infusion.
