What are hematopoietic stem cells?
Hematopoietic stem cells, also known as pluripotent hematopoietic stem cells, are the most primitive hematopoietic cells in the bone marrow differentiated from yolk sac totipotent mesenchymal cells. After mitosis of hematopoietic stem cells, about half of the daughter cells in the normal steady state still maintain all the characteristics of stem cells. The size of the total stem cell volume is maintained through this self-renewal, and this function can be maintained until the end of the life of a normal healthy organism. On the other hand, during mitosis, stem cells may undergo genetic rearrangements or translocations, resulting in changes in cell characteristics and a progressive differentiation pathway. Through this differentiation of stem cells into various groups of cells, the normal hematopoiesis of the organism is maintained and the need of the organism for various types of cells during the life course is ensured. Using these two important basic characteristics of hematopoietic stem cells, hematopoietic stem cell transplantation is used clinically to treat various diseases and to restore the hematopoietic and immune functions of patients.
Hematopoietic stem cell transplantation definition and classification: 1. Hematopoietic stem cell transplantation definition Hematopoietic stem cell transplantation: refers to the application of healthy hematopoietic stem cells to rebuild the patient’s blood and immune system.
2, hematopoietic stem cell transplantation classification according to the source of hematopoietic stem cells can be divided into the following categories: bone marrow transplantation, peripheral blood hematopoietic stem cell transplantation, umbilical cord blood transplantation: hematopoietic stem cells can be taken from bone marrow, peripheral blood or placental cord blood (referred to as cord blood), from bone marrow is called bone marrow transplantation, from peripheral blood is called peripheral blood stem cell transplantation, from placental cord blood is called Placental cord blood transplantation (referred to as cord blood transplantation).
HSCT can be divided into the following categories according to the HLA matching result between the donor and the recipient (patient): Allogeneic HSCT: transplantation between identical twins (twins).
Allogeneic HSCT: Donors who are other than identical twins, including: sibling donors with the same HLA type (referred to as mating type), related donors with semi-matched type (between parents and children, between siblings or other relatives, also known as haplotype transplantation) and unrelated donors with matched type. Transplantation from unrelated donors is also referred to as transplantation from unrelated donors.
Autologous hematopoietic stem cell transplantation: The patient’s own hematopoietic stem cells are first frozen and preserved and then transfused back to the patient after the patient receives high-dose chemotherapy and/or radiation therapy to rebuild his own blood and immune cells. Therefore, autologous HSCT is actually “bone marrow refuge” or “hematopoietic stem cell refuge. Autologous HSCT is usually indicated for patients whose bone marrow is not involved or whose disease is in a good state of complete remission.
What diseases can be treated by HSCT?
1, various leukemias, other hematological tumors such as multiple myeloma, lymphoma, myelodysplastic syndrome, etc.
2.Hereditary blood diseases and immune system diseases, such as thalassemia major, severe combined immunodeficiency disease, etc.
3, hematopoietic failure diseases, such as severe aplastic anemia, etc.
4.Non-hematopoietic system diseases, such as solid tumors, etc.