Lecture 4 1/23/24 Flashcards
Why are neutrophils and monocytes similar?
they derive from the same bipotential precursor cell
Which cells make up the mitotic pool in the bone marrow?
-myeloblasts
-promyelocytes
-myelocytes
What happens to the majority of myelocytes produced in healthy animals?
they undergo programmed cell death and do not mature
Which cells make up the maturation pool?
-metamyelocytes
-band neutrophils
-segmenter neutrophils
What are the differences between the circulating neutrophil pool and the marginated neutrophil pool?
-marginated neutrophil pool remains adhered to the blood vessel walls
-only circulating neutrophil pool neutrophils are collected in a blood sample
Why are there more marginated neutrophils in capillaries and post-capillary venules?
these vessels have lower blood flow rate, allowing more neutrophils to adhere to the vessel walls
How do the number of neutrophils in the MNP compare to the number of neutrophils in the CNP in different species?
-MNP = CNP in canine, equine, bovine
-MNP 3x greater than CNP in feline
What is physiologic/shift neutrophila?
the release of MNP neutrophils into circulation during stress, which can appear as inflammation on bloodwork
What is stress neutrophila?
decreased attachment of neutrophils to vessel walls and release of neutrophils from storage pool in response to increased cortisol levels
How long do neutrophil precursors remain in the proliferation pool?
2-3 days
How long do neutrophil precursors remain in the maturation pool?
2-3 days
How does WBC count compare to RBC count?
WBCs is a much lower proportion of blood than RBCs
Which WBCs are most common in the blood, in order?
-neutrophils
-lymphocytes
-monocytes
What are the effects of systemic recruitment on neutrophils?
increased:
-proliferation
-differentiation
-function
-bone marrow release
-margination/emigration
What are the methods for increasing neutrophil production?
-increased stem cell recruitment
-increased effective granulopoiesis (less programmed cell death, more cells mature)
-shortened maturation time
What are the characteristics of neutrophil release from the bone marrow?
-orderly and age-related
-neutrophils in the stored pool are released before new neutrophils are produced
What are the characteristics of left shift?
-seen during increased demand for neutrophils
-bands neutrophils and other, younger forms of neutrophils are prematurely released
What are the steps of leukocyte adhesion?
-margination
-rolling
-integrin activation by chemokines
-stable adhesion
-migration through epithelium
Which cells produce the chemokines that activate integrin?
macrophages
What are the functions of neutrophils?
-phagocytosis/killing bacteria
-kill/inactivate other pathogens
-inflammatory mediators
-tissue damage
Which “weapons” are used by neutrophils to kill bacteria/pathogens?
-myeloperoxidase
-lysozyme
-bactericidal/permeability-increasing protein
-collagenases
-gelatinases
-lactoferrin
Which neutrophil “weapons” fall into the azurophil granules category?
-myeloperoxidase
-lysozyme
-bactericidal/permeability-increasing protein
What are the characteristics of eosinophil production/kinetics?
-mature similarly to neutrophils
-have both storage and marginated pools
-30 min. circulating half-life
-emigrate into sub-epithelial sites
What are the functions of eosinophils?
-parasite elimination
-hypersensitivity/allergic reaction suppression
-infiltration of certain tumors
