Granulocytes
 Granulocytes have irregular-shape nuclei with 2 to 5
lobes. That is why they are called polymorphonuclear
leukocytes. The cytoplasm has granules that contain
reactive substances that kill microorganisms, and
enhance inflammation.
Basophlis
 Have nucleus with two lobes , and grains in the
cytoplasm that stain bluish black with basic dye. These
are non phagocytic cells that function by releasing
histamine, prostaglandins, serotonin and leukotrienes
from their granules on proper stimulation (interaction
with IgE antibodies).These chemicals released are
called vasoactive compounds because they act on
blood vessel walls.
basophiles
Esinophils
 Have a 2 –lobed nucleus connected by a slender thread
of chromatin, and granules stain red acidic dyes. They
are important in defence against protozoan and
helminthes, parasites by releasing cationic proteins
and reactive oxygen metabolites.
eosinophiles
Neutrophils
 Stain readily at neutral pH, have with 3 to 5 lobes, and
contain primary and secondary granules. The primary
granules contain peroxidase, lysozyme and other
hydrolytic enzymes, where as the secondary granules
have collagenase, lactoferrin and
lysozyme,Neutrophiles are highly phagocytic
cells.However , unlike macrophages, they do not reside
in healthy tissue but aggregate in tissue infected by
pathogens.
Neutrophils
Dendritic cells
 Dendritic cells can recognize pathogens by their
specific molecular patterns and can differentiate
between “self molecules” potentially pathogenic
foreign molecules. These are antigen –presenting
cells(for t helper cells) >they have long membrane
extension resembling the dendrites of the neurons.
These cells are found in node, spleen and thymus,
skin(langerhans cells) and other tissues.
Mast cells
 Mast cells are also derived from the bone marrow ,
they are found in the connective tissue. They contain
granules with histamine. Mast cells along with
basophiles are important in the development of
allergies and hypersensititives.
Staining
 Giemsa stain is used.It is mixure of methylene blue and
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eosin .
Make it 1:10 dilution or with (pH -6.8-7.2)
To stain a smear , take a slide with a fixed and dry
smear.Put on the slide a drop of stain until it is fully
covered .
Stain for about 16 min .
Rinse the slide distilled water at room temp.
Drain off the water and leave the slide to dry.
Then observe under microscope for different types of cells.
% of cells in the blood
 Neutrophils 50 – 70%
 Eosinophil 2 – 4 %
 Basophil
0, 5- 1%
 Lymphocyte 20- 40%
 Monocyte
3 – 8%