Clinical Use of Hematopoietic Stem Cells 1. Providing a functional immune system to individuals with a genetically immunodeficiency. 2. Replacing a defective hematopoitic system with a functional one (i.e. anemia). 3. Restoring the hematopoitic system of cancer patients after treatment with high doses of chemo- therapeutic agents or radiation.
Autologous : The recipient is also the donor. Syngeneic : The donor is the identical twin of the recipient. Allogeneic : The donor and the recipient are not genetically identical within the same species. Xenogeneic : The donor and the recipient are from different species.
Normal Adult Blood-Cell Count __________________________________ Cell type Cells/mm 3 % ___________________________________________________________________________________________________________________________ Red blood cells 5.0 x 10 6 Platelets 2.5 x 10 5 Leukocytes 7.3 x 10 3 Neutrophil 50 – 70 Lymphocyte 20 – 40 Monocyte 1 – 6 Eosinophil 1 – 3 Basophil < 1 ____________________________________________
- Lymphoid Cells B lymphocytes, T lymphocytes, Null Cells (natural killer, NK cells) -Mononuclear Phagocytes Monocytes, Macrophages, dendritic cell - Polymorphonuclear Cells (PMN) or granulocytic cells or granulocytes Neutrophils, Eosinophils, Basophils, Mast cells, Dendritic cells
Lymphoid Cells - 20% - 40% of the body’s white blood cells - 99% of the cells in the lymph - ~ 10 10 - 10 12 in the human body - Circulate in the blood and lymph - Migrate into the tissue spaces and lymphoid organs
T Lymphocytes: Thymus B Lymphocytes: Bursa of Fabricius ( 黏液囊 ) or Bone Marrow
T Lymphocyte Markers T cell receptor (TCR) CD4/CD8 CD28--------B7 CD45--------signal transduction
B Lymphocyte Markers Immunoglobulin (Ig) B220 (CD45R) MHC Class II CR1 (CD35) & CR2 (CD21) Fc RII (CD32) B7-1 (CD80) & B7-2 (CD86) CD40
Fate of antigen-activated small B lymphocytes Short half life 1-2 week
Null Cells - Most are large, granular lymphocytes called natural killer (NK) cells. - Against tumor cells and cells infected with some virus. - Constitute 5 - 10% of the lymphocytes in human peripheral blood. - NK T cells
Primary (central) lymphoid organs - Provide appropriate microenvironments for the development and maturation of lymphocytes. -thymus, bone marrow Secondary (peripheral) lymphoid organs - Trap antigen from tissues or vascular spaces and are sites where mature lymphocytes can interact effectively with that antigen. - lymph nodes, spleen, mucosal-associated lymphoid tissues (MALT), e.g., gut-associated lymphoid tissue (GALT).
Tertiary lymphoid tissue - Cutaneous-associated lymphoid tissues Lymphatic System ( 淋巴系統 ) - Once mature lymphocytes have been generated in the primary lymphoid organs, they circulate in the blood and lymphatic system, a network of vessels that collect fluid that has escaped into the tissues from capillaries of the circulatory system and ultimately return it to the blood.