White blood cells Flashcards
What are the 3 types of WBC’s
1- Mononuclear
2- Polymorphonucleaur
3- Phagocytes
What comes under mononuclear WBC’s
lymphocytes and monocytes
what comes under poly… WBC’s
neutrophils, eosinophils, basophils
What are normal neutrophil levels
1.8 - 7.5 (x 10^9)
what raises neutrophil levels
Bacterial infections, stress, exercise, and myeloproliferative diseases like leukemia.
what are normal lymphocyte levels
1.5 - 4.0 (x 10^9)
what raises lymphocyte levels
viral infections and lymphoproliferative diseases
What are normal monocyte levels.
0.2 - 0.8 (x 10^9)
what raises monocytes
infection, inflammation, tissue damage, monocytic leukaemia
what are normal eosinophils levels
0 - 0.4 (x 10^9)
what raises eosinophils
allergy, intestinal parasites, hypereosinophilic syndrome, eosinophilic leukemia.
what are normal basophil levels
0.01 - 0.1
what raises basophils
some myeloproliferative diseases.
What is the main role of a neutrophil
The elimination of invading bacteria and some fungi
What is the main role of a Eosinophils
Elimination of parasites, regulation of local immune and inflammatory responses.
What are the main roles of basophils
Immune system regulation, secretion of heparin and histamine, allergy, inflammation, and parasite defense.
What is nomenclature
staining granulocytes granules with Romanowsky stains
how are neutrophils stained
neutral-staining
how are eosinophils stained
with eosin (orange)
how are basophils stained
intensely with methylene blue
Where are neutrophils produced/matured
T cells, endothelial cells, monocytes, fibroblasts, and placenta.
Where are eosinophils produced/matured
T cells, endothelial cells, monocytes, fibroblasts.
Where are basophils produced/matured
T cells, B cells, endothelial cells, monocytes, fibroblasts
what is the maturation process of granulocytes
Blasts - promyelocytes - myelocytes - metamyelocytes - band form neutrophils - neutrophils
What is the daily granulocyte turnover
50 - 320 x10^9. About 370,000/sec
What and where is the neutrophil lifespan
They spend 7 hours in the peripheral blood, migrate randomly into tissues, and stay there for 20 hours. Often lost in the GI tract.
what and where is the eosinophil lifespan
8-12 hours in circulation then 8-12 days in tissues.
What and where is the basophil lifespan
between a few hours and a few days
What 2 things make up a neutrophils function
1- location by chemotaxis.
2- phagocytosis
why does chemotaxis require a vessel wall adhesion
When there is tissue damage it is easier to migrate to the tissue by adhesive membrane glycoprotein receptors.
why does chemotaxis need movement up a concentration gradient
Chemo-attractants bind to a specific neutrophil surface receptors.
What is the motility of a neutrophil
they are only able to crawl not swim
What are the 4 steps of phagocytosis
1- Opsonisation (coating) with IgM or IgG antibodies.
2- Particle attaches to a neutrophil via a receptor for the opsonin.
3- Pseudopodia enclose particle, which is ingested.
4- Microbial killing within 20 mins.
What are extracellular traps
Webs of DNA and proteases that trap and kill bacteria, produced by neutrophils
How do neutrophils ‘ nuclei shape affect their function
Lobulated nucleus to aid deformability and motility
What are the types of neutrophil granules
primary, secondary, and tertiary
What is myeloperoxidase definitely
A defect in microbial killing
What is respiratory burst failure
A inherited defect that causes metabolic failure of microbial killing
What is neonate neutrophils
They only have 20-27% chemotactic activity
What are eosinophils functions
To remove parasitic worms (helminth) infections by antibody dependent cell mediated toxicity. They are also key mediators of allergic inflammation.
Where are eosinophils found
The thymus, lower gi tract, ovary, uterus, spleen and lymph nodes. Found in the lunch in the case of airborne allergy
What is antibody dependent cell mediated toxicity
A mechanism of cell mediated immune defence where an effector cell actively lyses a target cell
Where do basophils mature
On the bone marrow for 2-7 days before circulating for 2 weeks
What do basophils do
Orchestrate local immunologic and inflammatory reactions. They secrete histamine and heparin
What is histamine
A chemotactic agent for eosinophils
What is heparin
An anticoagulant
What do monocytes do
Produce a number of adhesions which allows adhesions to surfaces such as endothelial cells. They can also release cytokines and kill infected host cells
What is the lifespan of a monocyte
Most are 24 hours
