HEMA

• Erythrocyte


  The red blood cell that carries oxygen from the lung to the tissues
• Erythrocyte production and destruction

  1. Erythroid progenitors (BFU-E and CFU-E)

  2. Erythroid precursor maturation

  3. RBC maturation series

  4. Erythrokinetics

  5. Erythrocyte destruction
• Study material presented


  07/04/2023
• The erythrocyte has one true function: To carry oxygen from the lung to the tissues, where the oxygen is released
• Nomenclatures used for naming erythroid precursors

  • Pronormoblast (Rubriblast)
  • Basophilic Normoblast (Prorubricyte)
  • Polychromatic (Polychromatophilic) Normoblast (Rubricyte)
  • Orthochromic Normoblast (Metarubricyte)
  • Polychromatic (Polychromatophilic) Erythrocyte or Reticulocyte
  • Erythrocyte
• Pronormoblast (Rubriblast)


  • Nucleus takes up much of the cell (N:C ratio of 8:1)
  • Contains one or two nucleoli
  • Dark blue because of RNA and ribosomes concentration
  • May show small tufts of irregular cytoplasm along the membrane periphery
• Basophilic Normoblast (Prorubricyte)


  • Chromatin begins to condense, revealing clumps along nuclear membrane periphery
  • N:C ratio decreases to 6:1
  • The cytoplasm appear deeper, richer blue than in the Pronormoblast, hence basophilic
• Polychromatic (Polychromatophilic) Normoblast (Rubricyte)

  • N:C ratio decreases from 4:1 to 1:1
  • Pink color due to hemoglobin accumulation over time and concurrent decreasing amounts of RNA, resulting in a mixture of pink and blue
  • Murky gray-blue color
• Orthochromic Normoblast (Metarubricyte)


  • Pyknotic nucleus
  • N:C ratio is approximately 1:2
  • Increase in salmon pink color
• Polychromatic (Polychromatophilic) Erythrocyte or Reticulocyte


  • Absence of nucleus
  • Bluish tinge due to residual ribosomes and RNA
  • A small amount of residual ribosomal RNA is present, however, and can be visualized with a vital stain such as new methylene blue
• Erythrocyte


  • Absence of nucleus
  • 7 to 8 um in diameter (Rodak's 6th Ed)/6 to 8 um in diameter (Brown's 6th Ed. Hematology)
  • On a Wright-stained blood film, it appears as a salmon-pink stained cell with a central pale area that corresponds to the concavity. The central pallor is about one-third the diameter of the cell
• Erythrokinetics


  1. Hypoxia detected by peritubular fibroblasts in the kidney

  2. Produces EPO

  3. EPO triggers release of RBCs from the BM

  4. Results in increased RBC production

  5. EPO has three major effects: early release of reticulocytes, prevents apoptosis, reduces transit time

  6. Measurement of EPO

  7. Therapeutic uses of EPO

  8. Other stimuli to erythropoiesis
• Erythrocyte destruction


  1. Macrophage-mediated hemolysis (extravascular hemolysis)

  2. Mechanical hemolysis (fragmentation or intravascular hemolysis)
• RBC lifespan is 90-120 days
• Erythrocyte


  The red blood cell that carries oxygen from the lung to the tissues
• Erythrocyte production and destruction

  1. Erythroid progenitors (BFU-E and CFU-E)

  2. Erythroid precursor maturation

  3. RBC maturation series

  4. Erythrokinetics

  5. Erythrocyte destruction
• Study material presented


  07/04/2023
• The erythrocyte has one true function: To carry oxygen from the lung to the tissues, where the oxygen is released
• Nomenclatures used for naming erythroid precursors

  • Pronormoblast (Rubriblast)
  • Basophilic Normoblast (Prorubricyte)
  • Polychromatic (Polychromatophilic) Normoblast (Rubricyte)
  • Orthochromic Normoblast (Metarubricyte)
  • Polychromatic (Polychromatophilic) Erythrocyte or Reticulocyte
  • Erythrocyte
• Pronormoblast (Rubriblast)


  • Nucleus takes up much of the cell (N:C ratio of 8:1)
  • Contains one or two nucleoli
  • Dark blue because of RNA and ribosomes concentration
  • May show small tufts of irregular cytoplasm along the membrane periphery
• Basophilic Normoblast (Prorubricyte)


  • Chromatin begins to condense, revealing clumps along nuclear membrane periphery
  • N:C ratio decreases to 6:1
  • The cytoplasm appear deeper, richer blue than in the Pronormoblast, hence basophilic
• Polychromatic (Polychromatophilic) Normoblast (Rubricyte)

  • N:C ratio decreases from 4:1 to 1:1
  • Pink color due to hemoglobin accumulation over time and concurrent decreasing amounts of RNA, resulting in a mixture of pink and blue
  • Murky gray-blue color
• Orthochromic Normoblast (Metarubricyte)


  • Pyknotic nucleus
  • N:C ratio is approximately 1:2
  • Increase in salmon pink color
• Polychromatic (Polychromatophilic) Erythrocyte or Reticulocyte


  • Absence of nucleus
  • Bluish tinge due to residual ribosomes and RNA
  • A small amount of residual ribosomal RNA is present, however, and can be visualized with a vital stain such as new methylene blue
• Erythrocyte


  • Absence of nucleus
  • 7 to 8 um in diameter (Rodak's 6th Ed)/6 to 8 um in diameter (Brown's 6th Ed. Hematology)
  • On a Wright-stained blood film, it appears as a salmon-pink stained cell with a central pale area that corresponds to the concavity. The central pallor is about one-third the diameter of the cell
• Erythrokinetics


  1. Hypoxia detected by peritubular fibroblasts in the kidney

  2. Produces EPO

  3. EPO triggers release of RBCs from the BM

  4. Results in increased RBC production

  5. EPO has three major effects: early release of reticulocytes, prevents apoptosis, reduces transit time

  6. Measurement of EPO

  7. Therapeutic uses of EPO

  8. Other stimuli to erythropoiesis
• Erythrocyte destruction


  1. Macrophage-mediated hemolysis (extravascular hemolysis)

  2. Mechanical hemolysis (fragmentation or intravascular hemolysis)
• RBC lifespan is 90-120 days