Transcript Cytoplasm - Austin Community College

MLAB 1315- Hematology
Fall 2007
Keri Brophy-Martinez
Unit 3: Leukocytes
NEUTROPHILS

Myelopoiesis - the production and
development of myeloid cells in the
bone marrow

Growth factors (colony-stimulating
factors - CSF’s) and interleukins
regulate blood cell development by:
Mediating proliferation
 Differentiation into cell lines
 Maturation of hematopoietic progenitor
cells

NEUTROPHILS

Three series of granulocytes (named for colors taken
up by granules in Wright’s stain)



Neutrophils
 Granules stain equally with eosin and methylene
blue
 Normal in circulation = 42 - 75%
Eosinophils
 Granules stain mainly red
 Normal in circulation = 0-4%
Basophils
 Granules stain mainly with methylene blue

Normal in circulation = 0-2%
Maturation of the neutrophilic series

Stem cell - an unspecified cell that
gives rise to a specific specialized
cell, such as a blood cell


Multipotential and cannot be identified
morphologically
Can self-renew and differentiate
Maturation of the neutrophilic series

Myeloblast


Size: 10-20µm
Cytoplasm



Nucleus





Slight
amount/blue
No granules (
possible Auer
rods to be
discussed in
another
section)
Round/Central
or eccentric
Reddish purple
1-3 nucleoli
Fine meshlike
chromatin with
no clumping
N:C ratio = 4:1
Maturation of the neutrophilic series

Promyelocyte
(progranulocyte)




Size: 10-20µm
Cytoplasm
 Increased amount/blue
 Fine, azurophilic,
nonspecific granules
present
Nucleus
 Round/Central or
eccentric
 Reddish-purple
 Fine, meshlike
chromatin beginning to
clump
 1-2 nucleoli
N:C ratio = 3:1
Maturation of the neutrophilic series

Myelocyte (last myeloid
cell capable of division)


Size: 10-18µm
Cytoplasm



Nucleus





Increased, bluishpink (“dawning of
neutrophilia”)
Fine azurophilic,
specific granules
Round or
oval/eccentric
Reddish-purple
Chromatin loosely
clumped
No nucleolus
N:C ratio = 2:1 or 1:1
Maturation of the neutrophilic series

Metamyelocyte (also
called “meta” or “juvenile”)


Size: 10-18µm
Cytoplasm



Nucleus






Moderate amount
Specific granules
(neutrophilic,
eosinophilic or
basophilic)
Indented (kidney-bean
shaped)
Central or eccentric
Purple
Clumped chromatin
No nucleolus
N:C ratio = 1:1
Maturation of the neutrophilic series

Band


Size: 10-16µm
Cytoplasm



Moderate amount
Specific granules
(see meta)
Nucleus



Elongated, narrow
band (sausage)
shape with uniform
thickness
Central or eccentric
Clumped, coarsely
granular chromatin
Maturation of the neutrophilic series

Segmented neutrophil, eosinophil or basophil


Size: 10-16µm
Cytoplasm




Neutrophil - specific fine violet pink
Eosinophil - red uniform specific granules
Basophil - coarse violet blue non-uniform specific granules
(Mast cell is a tissue basophil)
Nucleus



Neutrophil - purplish-red, clumped granular chromatin, 2-5
distinct nuclear lobes connected by a filament of chromatin
Eosinophil - deep blue purple, coarsely granular chromatin, 2
distinct lobes
Basophil - deep blue purple, coarsely granular chromatin, 2
nuclear lobes (sometimes obscured by cytoplasmic granules)
Maturation of the neutrophilic series
Function of the neutrophilic series


Neutrophils - defense against bacterial
infections
Eosinophils




Regulate inflammation
Respond to antigenic stimulation in chronic
allergies
Interact with larval stages of some helminthic
parasites
Basophils


Histamine in granules plays a role in acute,
systemic allergic reactions (sudden release of
histamine can cause anaphylactic shock)
Granules also contain heparin
MONOCYTES

Monopoiesis - the production and
development of monocytes,
macrophages and their precursors.
Monocytes are produced in the bone
marrow. Their primary function is
phagocytosis.
MONOCYTES

Other names for macrophages





Histiocytes in the loose connective tissue
Kupffer cells in the liver
Osteoclasts in the bone
Microglial cells in the nervous system
Also scattered throughout the body in all organ
tissues (spleen, lung, abdomen, etc.) One
monocytes have grown into macrophages, they
do not normally reenter the bloodstream
except in cases of inflammation
Maturation of the monocytic series

Monoblast


Size: 12-20µm
Cytoplasm



Nucleus







Blue, moderate
amount
No granules
Round, oval or
slightly folded
Eccentric
Reddish-purple
Chromatin fine and
thready
Vacuoles may be
present
1-2 nucleoli
N:C ratio = 4:1
Maturation of the monocytic series

Promonocyte (difficult to discern)


Size: 21-20µm
Cytoplasm





Nucleus





Paler gray-blue and abundant
“Bleb-like” pseudopods at periphery
May contain fine red “dust-like” particles
Vacuoles may be present
Round with chromatin creases or brain-like folding
Central
Reddish-purple with light clumping of chromatin
0-2 nucleoli
N:C ratio = 3:1 or 2:1
Promonocyte
Maturation of the monocytic series



Mature monocyte (Normal in circulation: 2-9%)
Size: 15-18µm
Cytoplasm





Nucleus





Pale gray-blue and abundant
Bleb-like pseudopods at periphery, variable shape
Numerous fine pale red dustlike granule scattered
throughout
Vacuoles common
Increased folding or elongated
Central
Purplish with finer clumped chromatin
No nucleoli
N:C ratio = 2:1 or 1:1
Monocyte
LYMPHOCYTES


Normal adult value: 21-51%
Produced in the bone marrow
(primary lymphoid tissue)
LYMPHOCYTES

Growth factors cause lymphs to
differentiate. They proliferate and
mature in the primary lymphoid
organs:
LYMPHOCYTES

Thymus - T cells

Function




Cellular immune response (they do not produce antibodies)
Regulate antibody reactions by helping or suppressing
activation of B lymphs. T cells act as “helper cells” (HIV or
AIDS virus causes a destruction of these helper cells), which
are instrumental in aiding B cells in antibody production, and
“suppressor cells”, which act as a “thermostat” to shut off
the system or keep it under control. The helper to suppressor
ratio is very important and is normally 2:1.
Protect against viral, bacterial, fungal or protozoan infection
Responsible for chronic organ graft rejection. (T cells have
many unique antigens on their cell surfaces, some of which
are the HLA - human lymphocyte antigen - markers.
Cytotoxic and helper T cells act against these HLA markers if
they are foreign to the host organism. HLA markers are
instrumental in chronic graft rejection and that is why tissue
typing is done to establish a good donor match.)
LYMPHOCYTES

Bone marrow - B cells

Function
Humoral (antibody) immune response by
transforming into antibody-producing
plasma cells
 Defense against encapsulated bacteria
such as streptococci
 Mediate hyperacute organ rejection

LYMPHOCYTES

Null cells - unknown maturation
sequence

Function
Destroy by lysis target cells (such as
tumor cells) by cytotoxins
 Play a role in inflammatory response
 Host defense when stimulated by
interferon against certain viruses
(cytomegalovirus - CM, and hepatitis) by
killing the virally infected target cell
before the virus replicates

LYMPHOCYTES

T and B cell lymphocytes cannot be
differentiated morphologically. They
are distinguished functionally and
by immunologic marker studies (to
be discussed later.) Null cells
appear as large lymphocytes with
azurophilic granulocytes and are
called large granular lymphocytes
(LGL).

Secondary lymphoid tissue


Lymph node, spleen, Peyer’s patches in
intestine and mucosal tissues such as
tonsils
Active immune response occurs in
above tissues where lymphs
communicate and interact with
antigen-presenting cells, phagocytes
and macrophages
Maturation sequence of lymphocytes

Lymphoblast (which is
preceded by a lymphoid
stem cell)


Cell size: 10-20µm
Cytoplasm



Nucleus




Blue/scanty
No granules, Auer
rods are never
present
Purple, smooth
chromatin
Round, central or
eccentric
1-2 nucleoli
N:C ratio = 4:1
Maturation sequence of lymphocytes

Prolymphocyte
(difficult to distinguish)


Size: 9-18µm
Cytoplasm



Nucleus




Blue, scanty
Usually granules are
absent, but a few
azurophilic granules
may be present
Purple, condensed
chromatin
Round or indented,
eccentric
0-1 nucleoli
N:C ratio = 4:1
Maturation sequence of lymphocytes



Mature lymphocyte
Cell size: 7-10µm (a typical
normal lymph has a
nucleus that is the size of
a normal RBC)
Cytoplasm



Nucleus



Light blue, scanty to
moderate
Few azurophilic granules
may be present
Purple, dense, clumped
chromatin
Round or indented,
eccentric
No nucleoli
Large lymphocytes versus monocytes

Size



Nucleus


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Large lymph: clumped, condensed
Mono: lacy, brainlike folds
Granules



Large lymph: 12-15µm
Mono: 15-18µm
Large lymph: large azurophilic, easy to count
Mono: red, fine
Cytoplasm


Large lymph: clear, nongranular, may be indented by red cells
Mono: “ground glass” appearance, projection of blunt pseudopod blebs
Maturation sequence of lymphocytes

Variant lymphs

Other terms used are reactive, atypical, Downey
cell, transformed, virocyte, plasmacytoid


Caused by antigenic stimulants such as viruses,
post-transfusion reactions and organ transplants
General characteristics







Increased size due to DNA activity in the nucleus and
RNA activity in the cytoplasm
Enlarged and/or monocytoid nucleus
Variation in nuclear chromatin pattern
Nucleus may contain 1-3 nucleoli
Abundant, sometimes foamy or vacuolated cytoplasm
Variation in cytoplasmic color - gray-blue to intense blue
Absence of granules in cytoplasm
Reactive lymphocyte
Plasma cells

Plasma cells




Function is the synthesis and excretion of antibodies
(immunoglobulins)
Normally not present in the peripheral blood; comprise 2% of
bone marrow cells. (May be seen in the peripheral blood in the
disease called multiple myeloma, a disease of uncontrolled
production of immunoglobulins.)
End stage of the B lymphocyte
Appearance




Size: 10-18µm
Cytoplasm is dark blue with perinuclear halo and may contain vacuoles
indicating antibody synthesis
Nucleus is round, eccentric, dark purple with dense clumped chromatin
Variant plasma cells


Grape or Mott cell - cytoplasm completely filled with red, pink or
colorless globules called Russell bodies
Flame cell - cytoplasm stains bright red-staining proteinaceous
material
Plasma cells