Leukocytes Flashcards
(37 cards)
Morphology of eosinophils?
- Highly basic (cationic) proteins: MBP and ECP
- Granules varies in size and shape.
What stage of leukopoesis is eosinophil recognize/differentiate?
After promyelocyte or myelocyte stage
Development of eosinophils: precursor? time? cytokines that promote maturation and survival?
- Develop from CFU-Eo in marrow
- 2-6 days for development
- IL-3, GM-CSF, IL-5
What unpopular pool exists in eosinophils?
Storage pool and marginal pool
How long does eosinophil live in blood? in tissue?
30 mins to less than an hour in blood; 6+ days in tissue. Numbers can be increased if influenced by cytokines.
Do eosinophil recirculate?
No. Same as neutrophils.
Where on the body do eosinophils preferentially reside?
Skin, gut, lung.
List products of eosinophils
Chemokines (eotaxin)
Antigen/antibody complexes
ECF-A (mast cells)
Histamine
LTB4
C5a, C567
PAF
Parasite and damaged tissue products
3 functions of eosinophils
- Helminth killing (by obsonization)
- Type 1 hypersensitivity / allergic reactions (by phagocytose immune complexes and neutralize mast cell products.)
- Phagocytose and kill bacteria.
What event causes eosinopenia?
Corticosteroid (see in stress leukogram) decrease eosinophilia of other causes.
What causes eosinophilia?
- Parasitism
- Allergies or hypersensitivities (skin, gut, lung)
- Fungal disease
- “Sensitized” T cell produced more eosinophilia at second exposure
- Paraneoplastic (MCT, lymphoma)
- Eosinophilic leukemia.
CBC does not yield eosinophilia. Is it a negative indication for eosinophilic inflammation?
No. Eosinophilic inflammation does not show eosinophilia all the time. Never r/o eosinophilic dz when having normal eosinophile.
What is the morphology of basophils?
- Staining due to highly acidic (negatively charged) protein in granules.
- Granules seen in cytoplasm, less numerous in dogs and paler in cats.
- Cytoplasm stain darker and is not as bright pink as eosinophils.
What is basophil progenitor? Cytokines that involved in production?
- Basophil progenitor is CFU-Baso.
- Cytokines IL-3, GM-CSF, IL-5.
How long do basophils last in blood? What is the relationship between them and mast cell numbers in tissue?
Basophil lasts for 6 hours in blood, 2 weeks in tissue.
Inversely relationship between basophils and tissue mast cell numbers.
What is basophil function?
- Basophil has similar content to mast cell, hence similar function.
- Degranulation in response to antigen binding and cross-linking surface Ig.
- Source of heparin.
- Activators of lipoprotein lipase.
What causes basopenia?
no such thing!
What causes basophilia?
(often accompanied with eosinophilia)
- Lipid disorders, myeloid neoplasm.
- Heartworm disease in cats!!!
What is morphology of monocytes?
- Largest cells in blood smear.
- Ameboid nuclei with blue-gray cytoplasm, often VACUOLATED.
The origin of monocytes: progenitor cell, major factors, time last, time circulation.
- Progenitor CFU-GM
- Factors IL-3, GM-CSF, M-CSF.
- Marrow production is 2-3 days, and no storage pool. Blood is storage pool.
- Marginal pool only in human, mouse, dog, rabbit.
- Blood circulate for 24 hours.
- Leave blood to become marcophages tissues “fixed” and “wandering”. They do not recirculate.
Monocyte function
- Immature macrophages
- Macrophages function: phagocytosis, APC, cytokine production, destruction of debris, pinocytosis and catabolism of plasma proteins, specialized “fixed” function (Kupffer cells).
What causes monocytosis?
- Inflammation
- Tissue macrophage accumulations
- Corticosteroids only in dogs.
- Persistent inflammation relating to viral, fungal, atypical bacterial infections.
- Disease w/ tissue demand for macrophages (immune mediated, necrosis, malignancy, hemolysis, pyogranulomatous disease).
What cause monocytopenia?
No one cares!
What does >4000 monocytes tell you?
It’s more than just a stress leukogram!
