A comprehensive guide for the stem cell research

Stem cells are undifferentiated cells classified into two groups, a) stem cells from embryos formed during the blastocyst phase of an embryological development and b) stem cells of an adult. Embryonic stem cells are derived from a 4-5 day old human embryo that is in the blastocyst phase of a development [1]. Adult stem cells exist throughout the body after embryonic development and are found inside of different types of tissues. Adult bone marrow and fat have stem cells along with other tissues [2]. Apart from these two types there is also embryonic germ cells which are collected from the fetus later in developmental process from gonadal ridge [3]. Adult stem cell serve as fresh source of cells in living organism They replace the cells that need to be replaced on regular basis like blood and other connective tissue [4]. Stem cell technology is rapidly growing in the field of regenerative medicine [5]. According to Patil AM, stem cell research has offered a new viable therapeutic option for degenerative diseases, injuries and other diseased condition. Stem cells are called as master cells with ability to grow into more than 200 cell types [6,7]. Based on their capacity to divide and differentiate they may be totipotent, pluripotent or multipotent [5].