HistoLab Blood

• Erythropoiesis


  Process of RBC production
• Erythropoietin


  Also known as the EPO hormone that stimulates RBC production; produced in the kidneys
• Erythrocytosis


  Increase in number of circulating red blood cells
• Erythrocytopenia


  Decrease in number of circulating red blood cells
• Anemia


  Decrease in oxygen capacity of RBCs; not a disease, but a symptom
• Macrocytic


  Bigger RBC than its normal size
• Microcytic


  Smaller RBCs than its normal size
• Normocytic


  RBCs has normal size
• Pokilocytosis


  Variation in RBC shape
• Anisocytosis


  Variation in RBC size
• Hyperchromic


  RBCs appear darker than normal due to increased hemoglobin content
• Hypochromic


  RBCs appear pale than normal due to a decreased hemoglobin content
• Normochromic


  Normal RBC hemoglobin content
• Blood


  A specialized connective tissue that has fluid extracellular matrix known as plasma, with suspended cellular elements
• General functions of blood

  • Transport oxygen and carbon dioxide
  • Transport nutrients to tissues and organs
  • Transport hormone to target organs
  • Maintain/regulate homeostasis (water and acid-base balance, body temperature, degree of irritability of tissues)
  • Serve as body's defense mechanism against infection
• Blood characteristics


  • pH level slightly basic with a range of 7.35-7.45
  • Higher density and viscosity than water due to its formed elements
  • Blood volume is around 80% of total body weight (males 5-6 liters, females 4-5 liters)
  • Blood is composed of 55% plasma and 45% of cellular elements
• Liquid components of blood


  • Plasma (fluid matrix of the whole blood, contains 90% water, inorganic salts, plasma proteins, gases)
  • Serum (liquid portion of the clotted blood without fibrinogen, contains growth factors and other proteins released by the platelets during the clotting process)
• Erythrocytes (RBC)


  Biconcave disc in 6-8 ɥm in diameter, formed in the bone marrow, non-nucleated, average lifespan of 30-120 days, contains hemoglobin (oxygen binding pigment responsible for the transport of most O2 in the body, compound of iron and protein, combines readily with O2 to form oxyhemoglobin)
• Types of leukocytes (WBC)


  • Granulocytes (neutrophils, eosinophils, basophils)
  • Agranulocytes (lymphocytes, monocytes)
• Neutrophils


  • Most abundant WBC in the body, cell size 10-15 ɥm, cytoplasm has fine lilac pink granules, nucleus has lobes connected by thin filaments and coarse clumped chromatin, normal relative count 50-70%, normal absolute count 1800-7800/ɥL or 1.8-7.8x10^9/L, active role in phagocytosis of bacteria and other small bacteria, primary WBC to arrive at an infested site
• Eosinophils


  • Cell size around 10-15 ɥm, cytoplasm has reddish orange large granules, nucleus has segmented two lobes with coarse chromatin, normal relative count 2-4%, normal absolute count 350-600/ɥL or 0.5-0.60x10^9/L, responsible for killing parasitic worms, modulates inflammatory responses
• Basophils


  • Cell size around 10-14 ɥm, cytoplasm has bluish black granules, nucleus is darkly stained and bilobed, normal relative count 0-1%, normal absolute count 0-20/ɥL or 0-0.02x10^9/L, releases heparin, histamine and peroxidase, involved in intermediate and delayed hypersensitivity reaction
• Staff cell (stab or band cell)


  • Cell size around 10-15 ɥm, cytoplasm almost similar to neutrophils with fine lilac granules, distinct indentation not more than ½ of total cell width, nucleus curved and elongated, normal relative count 2-6%, normal absolute count 350-700/ɥL or 0.3-0.70x10^9/L
• Atypical lymphocytes


  • Cell size 6-10 ɥm, cytoplasm appears sky-blue with small amounts of darkest blue cytoplasm and no granules, nucleus is compact, large and round, normal relative count 25-40%, normal absolute count 1000-4800/ɥL or 1.0-4.8x10^9/L
• Big lymphocytes


  • Cell size 12-15 ɥm, cytoplasm appears sky-blue with abundance of cytoplasm, nucleus is immature-looking with fine chromatin, normal relative count 25-40%, normal absolute count 1000-4800/ɥL or 1.0-4.8x10^9/L
• Monocytes


  • Cell size 14-20 ɥm, cytoplasm appears blue-grey, nucleus is smaller, partially lobulated, deeply indented and appears as a horse-shoe or coffee bean shape with fine parallel chromatin strands, normal relative count 2-8%, normal absolute count 300-800/ɥL or 0.3-0.80x10^9/L, precursor of macrophages and cells in connective tissues, serve as antigen presenting cells
• Thrombocytes


  • Irregular fragments of cells formed in the bone marrow from a much larger cell, non-nucleated, lightest element of blood, 2-4 ɥm in diameter, difficult to count as it adheres easily on surface and it easily disintegrates, normal value 150,000-400,000/mm3, maintains the integrity of blood vessels, forms the hemostatic plugs to stop blood loss from injured vessels, releases serotonin