1. HSC CMP Common Lymphoid Progenitor proB preB B CD4- CD8- CD4+ GMPMEP CD8+ Thymus Common Myeloid Progenitor Hematopoietic Stem Cell Granulocyte Macrophage Erythrocyte Megakaryocyte CD4+ CD8+ immature Hematopoiesis IgM IgD CLP

2. Thymopoiesis Thymus TN3 HSC 44+25- 4+8+ 44-25- 44+25+ 44-25+ 4+ 8+ TN4 TN2 TN1 Myeloid Erythroid CMP Common Myeloid Progenitor CD3-CD4-CD8- (TN, 3-5%) CD4+CD8+ CD4+ CD8+ Common Lymphoid Progenitor CLP

3. HSC CMP Common Lymphoid Progenitor proB preB B CD4- CD8- CD4+ GMPMEP CD8+ Thymus Common Myeloid Progenitor Hematopoietic Stem Cell Granulocyte Macrophage Erythrocyte Megakaryocyte CD4+ CD8+ immature Hematopoiesis IgM IgD CLP

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16. FACS Resolution of CMP and GMP

17. HSC CLP CMP Multipotentl Lymphoid Precursor proB GMPMEP Common Myeloid Progenitor Hematopoietic Stem Cell Granulocyte Macrophage Erythrocyte Megakaryocyte Common Lymphoid Progenitor CD45R CD43 IgM immaturemature IgD Myelopoiesis preB ETP CD4+ CD8+ Thymus Granulocyte Macrophage Progenitor Megakaryocyte Erythrocyte Progenitor

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31. HSC CMP Common Lymphoid Progenitor proB preB B CD4- CD8- CD4+ GMPMEP CD8+ Thymus Common Myeloid Progenitor Hematopoietic Stem Cell Granulocyte Macrophage Erythrocyte Megakaryocyte CD4+ CD8+ immature Hematopoiesis IgM IgD CLP

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33. HSC CMP Common Lymphoid Precursor proB preB B CD4- CD8- CD4+ GMPMEP CD8+ Thymus Common Myeloid Progenitor Hematopoietic Stem Cell Granulocyte Macrophage Erythrocyte Megakaryocyte CD4+ CD8+ immature Adult Hematopoiesis IgM IgD CLP

34. HSC CMP GMP MEP Common Myeloid Progenitor Hematopoietic Stem Cell Granulocyte Macrophage Erythrocyte Megakaryocyte Fetal Hematopoiesis B IgM Pro-B Pre-B Macrophage B/f

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52. HSC CMP GMP MEP Common Myeloid Progenitor Hematopoietic Stem Cell Granulocyte Macrophage Erythrocyte Megakaryocyte Fetal Hematopoiesis B IgM Pro-B Pre-B Macrophage B/f

53. Effects of Aging on Hematopoiesis

54. Embryogenesis Senescence

55. CD4 + CD8 + T cells B CELLS Memory B cells Activation Germinal center reaction MZ B cells Skewed V H repertoire T CELLS Memory T cells Activation Oligoclonal dominance Cytokine production Effector generation Thymus Bone Marrow IgM + B cells Aging Spleen Primary and secondary follicle with germinal center Periarteriolar lymphoid sheath MZ B Cells Exit of IgM+ cells T cell production Antibody-forming cells Aging