What are stem cells and what are they for?


A stem cell of any tissue is the cell that can generate all the cells of the tissue. The most famous and most accessible is the haematopoietic stem cell (HSC), which renews haematopoietic tissue. It generates red blood cells, cells which transfer oxygen; leukocytes, cells which defend the body; and platelets, cells which prevent haemorrhaging. There are three sources of stem cells in the human body: bone marrow, peripheral blood and umbilical cord blood. Haematopoietic stem cells are used in treating haematological diseases, such as leukaemias and lymphomas, serious bone marrow failures (aplastic anaemia) and serious failures of the immune system (immunodeficiency). After conditioning and chemotherapy, the patient is given an infusion of stem cells via peripheral blood, which is how sick bone marrow is replaced with healthy bone marrow. The ability of these cells to help regenerate other cells and tissues has been discovered recently and it may open new treatment possibilities for many diseases (so called regenerative medicine), such as myocardial infarction, spinal cord trauma, cerebral infarction or Alzheimer’s disease. Today, this is what most research is aimed at, which means that great advances in the area can be expected.