Lab 4 - WBC, inflammation Flashcards
What can inflammations be caused by
infection endotoxin mediated sterile necrosis (i.e. pancreatitis, tumour, trauma), chemical (injections, toxins, acids, alkalines), immune mediated (SLE)
Name the laboratory examinations used to examine inflammatory processes
haematology(qualitative and quantitative=complete blood count, CBC)
erythrocyte sedimentation rate (ESR) cytology
serum biochemistry
routine biochemical parameters (substrates, enzymes)
acute phase proteins microbiology
parasitology
immunology (ELISA, RIA etc. methods) molecular biology
morphological pathology, histology
What samplentupe is used for wbc counting
anticoagulated blood. Na2EDTA, K2EDTA, or Na- citrate can be used as anticoagulant
In case of bird, reptile, fish samples Li-, or Ca heparin is used.
wbc counting by hematology analysers - Give the different types
- automatic cell counters: the impedance is measured to give info about number and size of cells different cell layers.
- the laser beam method: the cells will scatter the laser beam and give two measures giving information about size, shape and number
How does automatic cell counters aka volumetric impedance method work?
SIZE AND NUMBER
the impedance gives A jump indicates a cell eg counted - small jump means small cell and vice versa. Its a very reliable methods as all cells are counted. The result is given in a histogram. The wbc and rbc are differentiated by heamolysing the rbc`s after making a dilution for the wbc
Differentiated wbc by size. Reagents are used to decr the size of lymphocytes and incr size of ng and macrophages
How does laser cell counters work
SIZE, NUMBER and SHAPE/INNER STRUCTURE, better that ACC
- Very reliable as all cells will scatter the light from the laser. cells flow through tube and are illuminated abd they will scatter the light
- the mistakes in ACC are more or less fixed in this machine eg. It wont count clumps
- gives a scattergram and histogram
Describe the two types of scatter and what they respresent (laser beam method)
x: Low angular scatter - size
Y: High angular side scatter - inner structure
X and y values create point on graph making the cloud
What is gating
The process of counting the points in the „cloud” giving the cell count of the similar cell types
How do you perform a qualitative blood count
Smears are examined using different stainings to enhance different traits. The smears are analysed at the middle of the slides and at the edges aswell.
First low power should be used, then high 1000x magnification can be provided by using immersion lens (and immersion oil). One should count at least 50-200 cells and differentiate according to the morphological pattern of the cell types and make the ratio in % among the different cell types
Neutrophil granulocyte cell line
myeloblast
promyelocyte myelocyte metamyelocyte (jugend) band forms (stab) segmented forms
Lymphoid cell line:
lymphoblast
small lymphocyte middle sized lymphocyte reactive T lymphocyte
Eosinophil cell line
young form (band nucleated) eosinophil granulocyte segmented form eosinophil granulocyte
Basophil cell line:
young form (band nucleated) basophil granulocyte segmented form basophil granulocyte
Monocyte cell line:
monocytic (young) form
reactive macrophage form
How do you determine the absolute wbc numbers
(relative % of the cell type/100) * WBC count
White blood cell (WBC) pools in the body:
In the bone marrow
mitotic- (very young cells, proliferating), maturation- (under differentiation) and storage- pools (mature, differentiated WBCs).
White blood cell (WBC) pools in the body:
In the blood vessels
In the blood vessels: marginal pool, cells attached to the inner surface of the blood vessels (mostly neutrophil granulocytes), cells can be mobilised very quickly from this pool!
White blood cell (WBC) pools in the body: In the circulating blood:
we take our sample from here, the circulating pool.
White blood cell (WBC) pools in the body: In the tissues of different organs
tissue pool
Physiological leukocytosis: acute
develops due to acute or chronic stress (epinephrine, norepinephrine, glucocorticoids) give their effects
catecholamines are visible within seconds (neutrophilia, lymphocytosisu- as cells are mobilised from the marginal pool /cells attached to the vessels, lymphatic vessels, and organs/
The effects of catecholamines during Physiological leukocytosis/inflammation
catecholamines are visible within seconds (neutrophilia, lymphocytosis- as cells are mobilised from the marginal pool /cells attached to the vessels, lymphatic vessels, and organs/
Physiological leukocytosis: chronic inflammation
can be detectable after hours (or in some instances minutes) (neutrophilia, lymphopenia, eosinopenia). The older neutrophils are mobilised from the bone marrow and marginal pools, they will age faster leading to hypersegmentation, the cellular proliferation is inhibited, lympholysis, and the eosinophils are inhibited from from leaving the BM
Physiological inflammation/ leukocytosis in cats
In cats stress can cause an extreme neutrophilia, as the marginal pool is bigger (two third of the total neutrophilic count) in cats.
Pathologic inflammation: Characteristics of acute and chronic
acute (increase of positive acute phase proteins (APP) in the blood and the decrease of negative acute phase proteins) inflammation
Chronic (is not part of the body’s natural healing. dilated blood vessels and a hyped up immune system) incr GCs by e.g. cushings or GC therapy
Stress leukogram/Chronic: right shift, Neutrophilia, leukocytosis, lymphopenia, eosinopenia
Acute: left shift, neutropenia, neutrophilia
Neutropenia in pathological acute inflammation
First stage of scute inflammaton bc the ng will travel to the tissues to work by the fsctors released by macrophages, the total wbc count will therefore initially decrease - we dont do blood samples in this part!