leucocyte physiology & function Flashcards
‘natural history’ of granulocytes
‘pools’/groups of leukocytes:
- proliferation, maturation & storage (bone marrow)
- Circulating (blood)
- Marginated: reversibly adherent to endothelial cells
- Tissues
Function of myeloid cells (3)
- can migrate out of circulation into tissues
- can do phagocytosis
- release granules by exocytosis
How do neutrophils move to attractants?
via chemotaxis. Neutrophil moves to attractant from low [ ] to high [ ] due to changes in cell’s cytoskeleton (microfilaments) => move in a repetitive wave-like motion
How does phagocytosis work in neutrophils?
Phagocytose -> Phagosome -> phagolysosome => substances released to kill & digest pathogen
Ways to assess WBC (4)
- total leukocyte count
- Differential blood smear evalution
- Absolute cell count
- specialised function assays
significance of neutrophilia
>7.0 x10^9 /L commonly due to: - inflammation - stress - myeloproliferative disease (neoplasm in haemapoetic sys.)
Significance of neutropenia
< 1.5 x 10^9 / L Commonly due to: - severe, acute inflammation - Immune-mediated processes - Disorders of bone marrow
Significance of lymphocytosis
>5.0 x10^9 /L Commonly due to: - inflammation (*viral inflammation) - Chronic inflammation - lymphoid neoplasia
Significance of Monocytosis
> 1.0 x10^9 /L
Commonly due to:
- inflammation (*chronic/ongoing)
- myeloproliferative disease
Significance of eosinophilia
>0.6 x10^9 /L Commonly due to: - parasitic disease - allergies - Myeloproliferative disease
Significance of basophilia
> 0.2 x 10^9 /L May be associated w/ (but not caused by) - Myeloproliferative disease - Allergic disease - infectious disease - miscellaneous
how do Automated analysers work in measuring WBC
- RBC lysed
- record FWD scatter = size
- record side scatter = granularity/complexity?
