Researchers prefer to use embryonic stem cells instead of adult stem cells because embryonic stem cell can differentiate into more type of cells.Human embryonic stem (ES) cells capture the imagination because they are immortal and have an almost unlimited developmental potential. Embryonic stem cells are pluripotent cells not unipotent. After many months of growth in culture dishes, these remarkable cells maintain the ability to form cells ranging from muscle to nerve to blood—potentially any cell type that makes up the body.