Chapter 2: Ontogeny of the Immune Cell Flashcards
Hematopoeisis involves the production, development, differentiation, and maturation of the blood cells (erythrocytes, megakaryocytes and leukocytes) from what type of cells?
multipotent stem cells
During embryogenesis and early fetal development, where is the site of hematopoiesis?
yolk sac
Where does hematopoeisis shift during the process of organogenesis?
liver and spleen
What is the difference in location of where hematopoeisis takes place in development from early years to adulthood?
from bone marrow in distal long bones to bone marrow in axial skeleton
Common lymphoid progenitor cells give rise to what type of cells?
B lymphocytes, T lymphocytes, and NK cells
What types of cells are produced by a common myeloid progenitor cell
erythrocytes, megakaryocytes/thrombocytes, mast cells, eosinophils, basophils, neutrophils, monocytes/macrophages, and dendritic cells
What are NK cells? What do NK cells recognize?
large granular lymphocyte that recognizes tumor and virally infected cells through non-specific binding
What in the body is needed to signal production of lymphoid cells from the multipotent stem cells?
IL-7
What in the body is needed to signal production of myeloid stem cells from multipotent stem cells?
GM-CSF (granulocyte/monocyte colony stimulating factor), IL-3
What signal in the body is needed to differentiate myeloid stem cells to eosinophil progenitors?
IL-5
What signal in the body is needed to differentiate myeloid stem cells to megakaryocytes?
thrombopoietin
What signal in the body is needed to differentiate myeloid stem cells to erythroid progenitor cells?
erythropoeitin from the kidney that is released when it senses low O2
Understand this diagram
Ontogeny of Immune Cells
Another name for neutrophil?
polymorphonuclear cell PMN
What is the most abundant circulating WBC in the blood?
Neutrophil
Describe the appearance of the neutrophil?
*granulocyte
* segmented lobular nuclei (3-5 lobes)
*small pink cytoplasmic granules
Describe the appearance of lymphocytes?
large, dark staining nucleus with a thin rim of cytoplasm
Describe the appearance of plasma cells?
- small eccentric nucleus (“clock face nuclei”)
- intensely staining Golgi apparatus
Describe the appearance of an NK cell?
- lymphocyte with large cytoplasmic granules
Where are lymphocytes found?
bloodstream, secondary lymphoid tissues
Where are plasma cells found?
bloodstream, secondary lymphoid tissue and bone marrow
Where are NK cells found?
bloodstream
What the the functions of neutrophils?
phagocytic activity aimed at killing extracellular pathogens
What are the functions of lymphocytes?
no function until activate in the secondary lymphoid tissues
What are the functions of plasma cells?
terminally differentiated B lymphocyte that secretes antibodies
What are the functions of NK cells?
kills virally infected cells and tumor cells
Surface markers on B lymphocytes
CD19, 20, 21
Surface markers of T lymphocytes?
CD3
Helper T cell surface markers?
CD4
CTL surface markers?
CD8
Surface markers of NK cells?
CD16, 56
Stem cells have what surface markers?
CD 34
Where is the tissue location of monocytes?
circulating blood cells
How would you describe the appearance of monocytes?
agranulocyte with a bean or kidney-shaped nucleus
What is the function of monocytes?
precursors of tissue macrophages
What is the location of macrophages?
residents in all tissues
What is the appearance of macrophages?
agranulocyte with a ruffled cytoplasmic membrane and cytoplasmic vacuoles and vesicles
What is the function of the macrophage?
- phagocyte
- professional antigen presenting cell
- T-cell activator
Where is the location of the dendritic cell?
resident in epithelial and lymphoid tissue
What is the appearance of the dendritic cell?
agranulocyte with thin, stellate cytoplasmic projections
What is the function of dendritic cells?
*phagocyte
* professional APC
*T-cell activator
What is the location of the eosinophil?
circulating blood cells recruited into loose connective tissue of the respiratory and GI tracts
How would you describe eosinophils?
granuloctye with bilobed nucleus and large pink cytoplasmic granules
Function of eosinophils?
- elimination of large extracellular parasites
- Type I hypersensitivity
What is the location of mast cells?
reside in most tissues adjacent to blood vessels
What is the appearance of mast cells?
granulocyte with small nucleus and large blue cytoplasmic granule
What is the function of mast cells?
- elimination of large extracellular parasites
- Type I HSR
What is the tissue location of basophils?
low frequency circulating blood cell
What is the physical appearance of basophils?
granulocyte with bi-lobed nucleus (which is barely seen because of the) large blue cytoplasmic granules
What is the function of basophils?
- elimination of large extracellular parasites
- Type I HSN
Percentage of PMNs of WBCs?
50 - 70%
What is the percentage of bands in the WBCs?
2 - 5%
What is the percentage of lymphocytes of the WBCs?
20 - 40%
What is the percentage of monocytes?
4 - 8%
What is the percentage of eosinophils?
2 - 4%
What is the percentage of basophils?
0.5 - 1%; <1%
Normal WBC count?
5 - 10 ( 5,000- 10,000) mm3