Blood

• Bone Marrow


  Found in the medullary canals of long bones and in the small cavities of cancellous bone
• Types of Bone Marrow

  • Red Bone Marrow
  • Yellow Bone Marrow
• Red Bone Marrow

  • Site of RBC production
  • Contains a reticular connective tissue stroma
  • Contains hemopoietic cords or island of cells and sinusoidal capillaries
• Stromal Cells


  • Meshwork of specialized fibroblastic cells that supports hematopoietic cells and macrophages
  • Contains adipocytes usually involves as storage energy
  • Under certain conditions, such as severe bleeding it hypoxia, yellow marrow turns red
• Hemopoiesis

  1. Blood formation

  2. In early development, the blood cells arise in the yolk sac mesoderm

  3. In second trimester, hemopoiesis occurs primarily in the developing liver, with the spleen playing minor role

  4. In third trimester, the skeletal elements begin to ossify and bone marrow develops and the bones become the major hemopoietic organ
• Progenitor Cells

  The progenitor cells for blood cells are often called colony-forming units (CFUs)
• Major Types of Progenitor Cells

  • Erythroid lineage of erythrocytes
  • Thrombocytic lineage of megakaryocytes
  • Granulocyte-monocyte lineage
  • Lymphoid lineage (B. T & NK cells)
• Hematopoietic Growth Factors


  • Also known as colony stimulating factors (CSF) or cytokines
  • Stimulate proliferation of progenitor and precursor cells
  • Promote cell differentiation maturation within specific cell lineages
• Examples of Stem Cell Factors

  • Granulocyte colony-stimulating factors (G-CSF)
  • Granulocyte-macrophage colony-stimulating factor (GM-CSF)
  • Monocyte colony-stimulating factor (M-CSF)
• Erythropoietin (EPO)


  • Hormones that help regulate and stimulate RBC production
  • Produced by kidney
• Thrombopoietin (TPO)


  • Primary regulator of megakaryopoiesis and platelet production
  • Produced primarily by liver to a limited extent by kidney
• Blood Composition

  • Plasma (55%)
  • RBC (45%)
  • Buffy Coat (<1%)

  
• Plasma


  • Water (90%), inorganic salts and ions (electrolytes), proteins, gases, nutrients, wastes, hormones
  • Transparent, yellowish fluid that contains numerous dissolved substances
• Serum

  • Counterpart of plasma
  • Usually used in immunoserology and Blood chemistry
  • Contains glucose, creatinine
• Blood Smear Preparation

  Feathery edge smear = good quality smear
• Blood Smear Staining

  • Romanowsky stain
  • Giemsa stain
  • Wright's stain
• Erythrocytes


  • Lack nuclei, flexible biconcave discs
  • Filled with the O2 carrying protein hemoglobin
  • Unstained- pale yellow or greenish yellow
  • Stained - salmon pink or pink color
  • Size: 7.5 and thickness of 1.9um
  • Life span: 120 days
  • Reference range: Men - 4.1 - 6.0 per uL, Women - 3.9 - 5.5 per uL
• White Blood Cells

  • Granulocyte
  • Agranulocyte
• Agranulocytes

  • Few azurophilic granules
  • Lack specific granules, but do contain some azurophilic granules (Lysosomes)
• Granulocytes


  Possess two major types of abundant cytoplasmic granules: lysosomes and specific granules
• Neutrophil or Polymorphonuclear


  • Also known as segmenters, POLY's, scavenger cells
  • Nucleus: 2 to 5 lobes
  • First WBC cells that respond when there is infection to kill and phagocytose bacteria
  • Life span: 1 to 4 days in tissue (8 hrs in blood)
  • Size: 9um in blood (10 - 12 in smears)
  • Reference range: 50 - 70% circulating leukocytes
• Eosinophils

  • Bilobed nucleus and far less numerous than neutrophils
  • Kills helminthic and other parasite; modulate local inflammation
  • Contains major proteins- an arginine rich factor that accounts for the granules acidophilia
  • Acts to kill parasitic worms if helminths
  • Life span: 3-8 hours in blood (8-12 days in tissue)
  • Size: 9 micrometer in blood (12-14 micrometer in smears)
  • Reference range: 2-5% of circulating leukocytes
• Basophils


  • Consists of 2 irregular lobes and a large specific granules that modulate inflammation, release histamine during allergy
  • The basophilic specific granules contains: Histamine: receptors for immunoglobulins E (lgE)
  • Life span: few days
  • Size: 12 to 15 micrometer in diameter (0.5 micrometer for specific granules)
  • Reference range: less than 1% of circulating leukocytes
• Monocyte


  • Nuclei are large and usually distinctly indented or C-shaped
  • Precursor of macrophages and other mononuclear phagocytic
  • Life span: 1-2 days in blood (70 days in tissues)
  • Size: 9 - 12um blood (17-20 in smears)
  • Reference range: 3% to 7% of circulating leukocytes

  
• Lymphocyte


  • Smallest leukocyte with spherical nuclei
  • Involved in viral infection
  • Life span: hours to years
  • Size: 9 - 12 um med to large, 6 - 9 um small
  • Reference range: 20% to 40%
• Overall WBCs Reference Range

  4,500 - 11,000 per uL
• Platelets


  • Very small, non-nucleated, membrane-bound cell fragments
  • Promote blood clotting and help repair minor leaks in the walls of small blood vessels
  • Life span: 9-12 days
  • Size: 2-3 um in diameter
  • Reference range: 150k to 400k per uL
  • Note: Super baba ng platelets check the quality (possible clumping)
  • Binabasa as 1 kapag may clumping
  • Dengue: virus attacks the platelets