A unique property of stem cells is their ability to differentiate, which means they can form specialized cells. Another special property is their ability to proliferate, or divide repeatedly. As mentioned, unipotent stem cells have a very limited ability to differentiate relative to other stem cells such as pluripotent, totipotent or multipotent cells. Their ability to self-renew, however, does make them a valuable candidate for therapeutic use in treating disease. They are thus able to generate healthy and viable cells for transplant purposes.