Leukocytes Flashcards
Mammalian leukocytes include what?
neutrophil, monocyte, eosinophil, basophil, lymphocyte
The avian equivalent of mammalian neutrophils
Heterophils
(Mammals) have multiple nuclear lobes separated by constrictions (polymorphonuclear) and have colorless to pink cytoplasm.
Neutrophils
Stain reddish-purple with Romanowsky stains but generally do not stain and are not visible after the promyelocyte stage of development,
Primary or azurophilic granules
Granule contents include microbiocidal elements (lactoferrin, lysozyme, cathelicidins) and enzymes (collagenase, apolactoferrin plasminogen activator)
-usually not visible with Romanowsky stain.
Secondary or specific granules
Stages of Neutrophil maturation
- Myeloblast
- Promyelocyte (progranulocyte)
3.Myelocyte - Metamyelocyte
5.Band - Segmenter
Compartments of the bone marrow neutrophils
Proliferation or Mitotic compartment
-Myeloblasts, promyelocytes, myelocytes
Maturation stage compartment
-Metamyelocytes, bands, segmenter
Mechanisms for increased neutrophil production
- Increased stem cell recruitment
- Increased effective granulopoiesis
- Shortened marrow transit or maturation time.
Neutrophil release is mediated by?
G-CSF, GM-CSF, C5a, tumor necrosis factor
Primary function of neutrophils
Phagocytosis and microbial action; effectively conducted in tissue but not in blood.
1. Adherence to and emigration
2. Chemotaxis
3.Ingestion and degranulation
4. Bacterial killing
Generally the largest leukocytes circulating in health. the nucleus is Oval, reniform, bilobed, or trilobed with lacelike chromatin. Cytoplasm is blue-gray, granular, and may or may not have vacuoles.
Monocyte
Maturation sequence of a monocyte
- Monoblast
- Promonocyte
- Monocyte
have two to three nuclear lobes separated by constrictions
Eosinophils
Eosinophil function
They attach to and kill helminths in a process mediated by antibody, complement, and T lymphocyte perforins. They may also suppress hypersensitivity reactions.
Basophil function
-Participation in immediate and delayed hypersensitivity reactions (Histamine release)
-Promotion of lipid metabolism
-Prevention and promotion of hemostasis via heparin release and kallikrein activity.
an increase in the total WBC count
Leukocytosis
Increase in neutrophils
Neutrophilia
decrease in the total WBC count
Leukopenia
The cytoplasm of toxic neutrophils has a diffuse blue color from retained ribosomes
Cytoplasmic basophilia
Foamy appearance. a more severe manifestation of toxic change. This change results from cytoplasmic granule dissolution
Cytoplasmic vacuolation
These structures are blue to gray, angular, cytoplasmic inclusions representing retained aggregates of rough endoplasmic reticulum.
Dohle bodies
