1. White Blood Cell Differential Count
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2. Leukocytes (WBCs)
5 types of WBCs characterized as granular or agranular
all function in defense
average WBCs/mm3 of blood
variable “life” span depending on type of WBC- days (neutrophils) to decades (lymphocytes).

3. Differential Count & Functions of WBCs
Neutrophils %, function in acute bacterial infections; phagocytic.
Eosinophils – 2-4%: active against parasites & elevated in allergic reactions; destroy antibody-coated antigens by phagocytosis.
Basophils – 0-1% : release chemicals mediators (histamine, heparin) during tissue inflammation.

4. Differential Count & Functions of WBCs
Lymphocytes – 25-40%: function in “immunity” – specific resistance to disease
Monocytes – 3-8%: function in chronic bacterial infections; migrate into tissues to become “macrophages”

5. MYELOBLAST PROMYELOCYTE MYELOCYTE
No Granules, N/C ratio 6/1, Pale blue cytoplasm , ~ 2% of normal marrow, Not present in blood of Healthy Persons.
Usually larger than MYELOBLAST, Granules are large & azurophilic, N/C ratio is 4/1.
: Round or Oval cell with a round nucleus, Granules are either primary azurophilic or secondary specific according to WBC type: (Neutrophil, Eosinophil or Basophil).
MYELOBLAST: 16 um, 2 to 6 Nucleoli, No Granules, N/C ratio 6/1, Pale blue cytoplasm , ~ 2% of normal marrow, Not present in blood of Healthy Persons.
PROMYELOCYTE: Usually larger than MYELOBLAST, Granules are large & azurophilic, N/C ratio is 4/1.
MYELOCYTE: Round or Oval cell with a round nucleus, Granules are either primary azurophilic or secondary specific according to WBC type: (Neutrophil,
Eosinophil or Basophil).
META-MYELOCYTE: Kidney-shaped nucleus
STAB or BAND FORM: Smaller cells with a U-shaped nucleus

6. STAB or BAND FORM Kidney-shaped nucleus
META-MYELOCYTE
STAB or BAND FORM
Kidney-shaped nucleus
Smaller cells with a U-shaped nucleus
MYELOBLAST: 16 um, 2 to 6 Nucleoli, No Granules, N/C ratio 6/1, Pale blue cytoplasm , ~ 2% of normal marrow, Not present in blood of Healthy Persons.
PROMYELOCYTE: Usually larger than MYELOBLAST, Granules are large & azurophilic, N/C ratio is 4/1.
MYELOCYTE: Round or Oval cell with a round nucleus, Granules are either primary azurophilic or secondary specific according to WBC type: (Neutrophil,
Eosinophil or Basophil).
META-MYELOCYTE: Kidney-shaped nucleus
STAB or BAND FORM: Smaller cells with a U-shaped nucleus

7. SEGMENTED
GRANULOCYTES
Neutrophils have pink cytoplasm with fine evenly-distributed neutrophilic granules
2 to 6 nuclear segments

8. Eosinophils have bi-lobed nuclei & orange Course granules
SEGMENTED
GRANULOCYTES

9. Basophils have bi-lobed nuclei & deep blue granules
SEGMENTED
GRANULOCYTES

10. Agranulocytes Monocytes Lymphocytes Pleuripotential stem cell
Multipotential
stem cell
Monocytes
Lymphocytes

11. Monoblasts Monocytes Bigger than myeloblasts Largest blood cells
Usually kidney-shaped nuclei

12. Lymphoblast Lymphocytes
Nucleus fills the cell
Lymphocytes
Small LC have a round, nucleus that fills the cell & have size of RBC
Large LC is double the size

13. White Blood Cell Differential Count
Usually performed by visual examination of blood film that are prepared on slides by the spread technique

14. Equipments: Smooth glass spreader Glass slides Capillary tubes
Light microscope
Mechanical or electronic counter
Leishman stain

15. Specimen
Fresh blood with no anticoagulant
EDTA –anticoagulated blood

16. Procedure:
Place small drop of blood on the center of clean dry glass slide about 1 cm from the end
Then without delay, a spreader in front of the drop at angle of 30o to the slide and move it back to make contact with the drop
With a steady movement of the hand, spread the drop of the blood along the slide

17. Procedure… 4-The film should be allowed to be dry in the air
5-The film should be labeled immediately after it had been dried by pencil
6-Using Leishman’s stain, flood the slide with the stain for 2 min
7-Add double the volume of water and stain the film for 5-7 min
8-Wash it in a stream of water.

18. Procedure…
9-After the back of the slide has been wiped clean, sit it upright to dry
10-Examine the film using x40 objective in a strip, running the whole length of the film
11-Avoid the lateral edges
12-Inspect the film from head to tail
13-Count 200 cell or more to get an accurate result using counter.

19. Absolute count Absolute Leukocytes count:
= Relative count * Total Count
e.g.
if Neutrophils = 55% , Total Count = 6000 C/µl
So, Absolute neutrophil count= 0.55 * 6000
= 3300

20. White blood cell count 4.0–11.0 × 109/L
Differential white cell count
Neutrophils: –7.0 × 109/L (50–70%)
Lymphocytes: 1.0–3.0 × 109/L (25–40%)
Monocytes: –1.0 × 109/L (3–8%)
Eosinophils: –0.5 × 109/L (2–4%)
Basophils: –0.1 × 109/L (0-1%)

21. Correcting WBC for nucleated RBC
Corrected WBC=
total cell counted – (total cell counted * no. of nRBC\100)