Chapter 8 Essential Hematology (WBCs) Flashcards
What 2 categories can white blood cells be divided into?
Phagocytes and immunocytes.
What are the 3 types of granulocytes?
- Neutrophils
- Eosinophils
- Basophils
The WBC phagocytes consist of what cell types?
Granulocytes and monocytes.
Which WBCs are normally found in peripheral blood?
Only mature phagocytes and lymphocytes.
Which cell types are the immunocytes of the WBCs?
The lymphocytes, their precursors, and plasma cells.
What is the normal range of total leukocytes?
4-11x10^9/L
What is the normal range of neutrophils?
2.5-7.5x10^9/L
What is the normal range of lymphocytes?
1.5-3.5x10^9/L
What is the normal range of monocytes?
0.2-0.8x10^9/L
What is the normal range of eosinophils?
0.04-0.4x10^9/L
What is the normal range of basophils?
0.01-0.1x10^9/L
Characteristics of neutrophils?
Dense nucleus with 2-5 lobes. Pale cytoplasm with an irregular outline containing many fine pink-blue (azurophilic) or grey-blue granules.
What are the 2 categories of neutrophilic granules?
- Primary: appear at promyelocyte stage
2. Secondary: appear at myelocyte stage and predominate in the mature neutrophil
What is the lifespan of neutrophils in the blood?
6-10 hours
List the cell stages of the neutrophil in order.
- Myeloblast
- Promyelocyte
- Myelocyte
- Metamyelocyte
- Band neutrophil
- Mature neutrophil
What are the characteristics of the myeloblast?
Cell of variable size. Large nucleus with fine chromatin. 2-5 nucleoli. Basophilic cytoplasm with NO granules.
What are the characteristics of the myelocyte?
Nuclear chromatin more condensed and nucleoli not visible.
What are the characteristics of the metamyelocyte?
Non-dividing cells. Indented or horseshoe-shaped nucleus. Cytoplasm filled with primary and secondary granules.
Can band neutrophils be seen in peripheral blood?
Yes
How can you distinguish band neutrophils from mature neutrophils?
Bands do not contain the clear, fine filamentous connections between nuclear lobes as seen in mature neutrophils.
What are the characteristics of monocytes?
Larger than other peripheral blood leukocytes. Large central oval or indented nucleus with clumped chromatin. Abundant cytoplasm stains blue and contains many fine vacuoles (gives a ground glass appearance). Cytoplasmic granules often present.
What are the 2 monocyte precursors found in the bone marrow?
- Monoblasts
2. Promonocytes
What are the characteristics of eosinophils?
Similar to neutrophils except cytoplasmic granules are coarser and stain red. Rarely more than 3 nuclear lobes.
T or F. The blood transit time for eosinophils is longer than for neutrophils.
T
What are the 3 roles of eosinophils?
- Allergic responses
- Parasite defense
- Removal of fibrin formed during inflammation
What are the characteristics of basophils?
Many dark cytoplasmic granules which overlie the nucleus and contain heparin and histamine. IgE on surface. Become mast cells once they enter tissue.
In granulopoiesis, which cells are proliferative? Non-dividing?
Proliferative: myeloblasts, promyelocytes, myelocytes.
Non-dividing: metamyelocytes, band and segmented granulocytes
T or F. Large numbers of band and segmented neutrophils are held in the marrow as a reserve pool or storage compartment.
T
In the bone marrow, are myeloid cells or erythroid cells more abundant?
Myeloid cells: 2-12x more.
T or F. Normally, the bone marrow contains 10-15x the number of granulocytes found in peripheral blood.
T
What are the 2 pools of granulocytes found in the bloodstream?
- Circulating pool: included in blood count
2. Marginating pool: not included in blood count
How many days do granulocytes spend in the tissues before they are destroyed?
4-5 days
What are the myeloid growth factors involved in control of granulopoiesis?
IL-1, IL-3, IL-5, IL-6, IL-11, GM-CSF, G-CSF, and M-CSF.
What do they myeloid growth factors do?
Stimulate differentiation and proliferation as well as play a role in the function of mature cells.
In an infection, what 3 molecules stimulate stromal cells and T cells to increase production of growth factors which increase granulocyte and monocyte production?
- Endotoxin
- IL-1
- TNF
Endothelial cells and FBs increase production of what 2 molecules when stimulated by TNF and IL-1 from monocytes?
- GM-CSF
2. G-CSF
Clinical administration of G-CSF IV or subq does what?
Produces an increase in circulating neutrophils. Short-acting G-CSF given daily. Longer acting pegylated G-CSF given once every 7-14 days.
What are the 7 clinical indications of administering G-CSF?
- Post-chemo, radiotherapy, or stem cell transplant
- Acute myeloid leukemia
- Myelodysplasia
- Lymphomas
- Severe neutropenia
- Severe infection
- Peripheral blood stem cell harvesting
How many hours do monocytes circulate in the blood before entering tissues to mature and carry out their function?
20-40 hours
When monocytes enter the tissues, what do they become?
Macrophages (or histiocytes).
How long can monocytes live in tissue?
Several months to years.
What is one very important lineage of monocytes?
Dendritic cells: Ag presentation to T cells.
What 2 molecules are involved in the production and activation of dendritic cells?
GM-CSF and M-CSF
Monocytes become what in the kidney? Brain? Gut? Lung? Liver? Spleen? BM? Lymph node?
Kidney: intraglomerular mesangial cells Brain: microglia Gut: serosal macrophages Lung: alveolar macrophages Liver: Kupffer cells Spleen: sinus macrophages and APCs BM: macrophages and APCs Lymph node: macrophages and APCs
What are the 3 phases of neutrophil and monocyte function?
- Chemotaxis
- Phagocytosis
- Killing and digestion
What are the 2 classes of chemokines?
- CXC: act on neutrophils
2. CC: act on monocytes, basophils, eosinophils, and NK cells (ex. MIP-1a, RANTES)