Lutfi Al-maktri1 , Faisal Ali2 ,and Mohammed AK. Al-Nuzaily 3
1Haematology Department, Faculty of Medicine and Health Sciences, Sana a University, Yemen.
2Department of Nutrition and Dietetics, Metabolism and Genomics, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
3Kuwait University Hospital, Haematology Department, Faculty of Medicine and Health Sciences, Sana a University, Yemen.
Stem cells The discovery of stem cells is largely referred to Professor Alexander A. Maximow from 1922 to 1928. He was a Russian-American physician, embryologist and histologist. He developed his theory that all cells come from the same precursor cell, which he later calls as stem cells. He proposed the existence of hematopoietic stem cells and described his unitarian theory of hematopoiesis during that event. He was the first person to use the term “stem cells” for scientific and medical purposes. Later, other physicians and medical researchers such as Joseph Altman, Gopal Das, Andre Gernez, McCulloch and till discovered various characteristics of stem cells. They first found methods to isolate stem cells from mouse and then human embryos. Later, they grow the cells in the.
laboratory for infertility purposes through in vitro fertilization procedures (1). Generally, stem cells are defined as unspecialized cells with unlimited proliferation capacity that can differentiate into various cell types with specific functions. Two types of stem cells have been identified based on their origin, namely a) embryonic stem cells (ES) or fetal stem cells and b) adult stem cells. ES cells are obtained from tissues of a developing human fetus and these cells have some characteristics of the tissues they are taken from, while adult stems cells are obtained from some tissues of the adult body, for example, bone marrow. Bone marrow is a rich source of stem cells that can be used to treat some blood diseases and cancers (2, 3). Fetal stem cells are present during the early stages of embryonic development in the inner cell mass of the