WBCS or white blood cells include granulocytes like neutrophils, eosinophils, and basophils and agranulocytes like lymphocytes and monocytes. Leucopoiesis is the production and maturation of WBCs from pluripotent stem cells in the bone marrow. WBCs have important functions like phagocytosis of pathogens, response to inflammation, and fever response. Differential leukocyte counts provide the percentage distribution of different WBC types in blood and are used to detect infections, allergies, and other conditions. Leukemias are malignant diseases where there is an abnormal increase in immature white blood cells.

1. WBCS [WHITE BLOOD CELLS]
• INTRODUCTION
• TYPES
• LEUCOPOIESIS
• STRUCTURE
• FUNCTIONS
• APPLIED ASPECTS

2. • INTRODUCTION= [Leucocytes]
• TYPES = Depending upon granules – presence / absence in
the cytoplasm of the leucocytes.
Depending upon the Leishman’s stain.
There are two types.
• 1) Granulocytes 2) A granulocytes
- Granules are present - Granules are absent
- There are three types [ 3 ] - There are two types [ 2]
1) Neutrophils – 50- 70 % 1) Lymphocytes-
2) Eosinophils – 1 – 4 % - large
3) Basophil – 0 – 1 % - small
2) Monocytes

3. • Total Leucocytes count = 4000- 11000cells /cmm
• Leucopoiesis = Production and maturation of WBCs
• PHSC
• Some remain dormant committed stem cell
in the bone marrow
CFU - GM
• Lymphoblast .Neutrophil .Monocytes
• Prolymphocyte .Eosinophil
• Lymphocyte .Basophil

4. • PHSC
• GM-CSF
• Myeloblasts Monoblast
• Promyelocyte Promonocyte
• Myelocyte
• Metamyelocyte
• Eosinophil, Basophil Monocytes
Neutrophil

5. • Total WBC Count- 4000-11000cells/mm3
• Differential Leucocytes count = [ DLC]
• Is the percentage distribution of different types of
leucocytes in the blood.
- Neutrophil – 50 – 70 %
- Eosinophil - 1 – 4 %
- Basophil - 0 – 1 %
- Lymphocytes – 25 – 30 %
- Monocytes - 2- 8 %
• Neutrophil=[ polymorphonuclear leukocyte ]
• DLC = 50 – 70 %

6. • Cell size= 10 – 14 micrometer
• Nucleus = multilobed [1- 5 lobes] - connected by thin band
of chromatin. Deep blue colour.
• Cytoplasm = pale bluish – pinkish colour
• Granules = Fine, sand like, pin-point granules- which takes
both stain.
• Arneth count / Index= percentage distribution of
Neutrophils according to the number of lobes of their nucleus

7. • Functions=
1) Phagocytosis -The process of engulfment and destruction
of solid particulate materials by the cell
2) Reaction of inflammation - vasodilatation, oedema.
3) Febrile response – Releases fever producing substances –
Endogenous pyrogen.

8. • Variations in counts =
Neutrophilia – increase in neutrophil count
Neutropenia -decrease in neutrophil count

9. • Eosinophil =
• DLC = 1-4 %
• Cell size = 10-14 micrometer
• Nucleus = Bilobed / spectacle shaped / Telephone receiver
shaped-connected by thick chromatin . Deep blue colour

10. • Cytoplasm= pinkish colour
• Granules = Coarse, bright red colour – which are not
covering the nucleus
• Functions=
• 1) Mild Phagocytosis
• 2) Role in parasitic infestations =
- damages parasite’s larvae
- destroys and kills helminths, bacteria

11. • 3) Role in Allergic reactions- Eosinophils reduces
inflammation
- it inhibits release of inflammatory substances
- It detoxifies inflammation inducing substances like
histamine, Bradykinin
- They phagocytose antigen – antibody complexes
• Variations in count=
Eosinophilia =increase in eosinophil count
Eosinopenia = decrease in eosinophil count

12. -
• Basophil =
• DLC - 0 – 1 %
• Cell size = 10 – 14micrometer
• Nucleus = 2-3 lobes / S- shaped- but actually is not visible-
covered by the granules.

13. • Cytoplasm = slight bluish
• Granules = coarse, big, plenty, overlapping the nucleus,
bluish- blackish colour.
Functions=
• 1) Mild Phagocytosis
• 2) Role in allergic reactions- where it produces
inflammation.( produces allergic Reactions).
• 3) Releases heparin – prevents clotting of blood
Variations=
• Basophilia- increase in basophil count
• Basopenia – decrease in the count

14. • Mast Cell = a large tissue cell – resembling the Basophil –
Present in the – Bone marrow
- Beneath the skin
- Tissues
- It will not enter into the blood – it has a role in allergic
reactions.
• Lymphocytes=
• DLC – 25- 40 %

15. large small
• Size - 10 – 14 micron 7- 10 micron
• Nucleus - central, big, central, big,
Bluish colour Bluish colour
• Cytoplasm - scanty, very scanty,
Light blue colour Light blue colour
• Granules - None, few none, few
• Functions=clinically lymphocyte are two types
1) T- lymphocytes- Cell – mediated Immunity
2) B- lymphocytes-Humoral/Antibody –mediated Immunity

16. • Variations=
• Lymphocytosis =increase in lymphocyte count
1) Chronic infections- T.B, Hepatitis
2)Viral infections –
3) Leukaemia
• Lymphocytopenia= decrease in lymphocyte count
• Monocytes=
• DLC – 2- 8 %

17. • Size -18 -22 micrometer - largest WBC
• Nucleus – large, notched, kidney shaped, Eccentric, bluish
colour
• Cytoplasm- Clear, pale blue, moderate amount
• Granules – None / few
• Functions=
• 1) Phagocytosis

18. • Variations
• Monocytosis= increase in monocyte count
• Monocytopenia= decrease in count

19. Macrophages = Is modified form of Monocyte
Monocytes remain in the circulation for about [ 10 -20 hrs]
-Enters into the extra vascular tissue
-Converted into the Macrophages
-This system is called as Tissue Macrophage System
or Reticuloendothelial System
- They can live there for months to years
• Leukaemias = Group of malignant diseases of blood in
which there is increase in total WBC count associated with
presence of immature WBCs count 50000---3lacs / cmm.