Test 1 Flashcards
Where is red marrow in adults? in kids?
Adult red marrow only in epiphysis and metaphysis of trabeculae’s osteons
Kids: everywhere in bones, all of their marrow
Where is hemoatopoetic activity in first month of fetal life?
months 2-6?months 8-9?
Which month does hematopoeisis start in the marrow?
First month of fetal life hematopoeisis: yolk sac
Months 2-6: liver and spleen
months 8-9: marrow… starts month 4
Where is yellow marrow in adults? in kids?
Yellow marrow in adults: diaphysis’s medullary cavity, middle of long bones
Kids: nowhere
Differentiate totipotent, pluripotent, multipotent, and unipotent stem cells
- Totipotent –differentiate into all tissues of embryo plus extra-embryonic tissue, Present very early in fertilized egg
- Pluripotent – differentiate into all tissues of embryo
- Multipotent – differentiate into cells of a given germ layer, Most “adult” stem cells, Like Hematopoietic stem cells
- Unipotent – differentiate into a single cell type, Like lymphoid progenerators that can generate into B/T/K lymphocytes
what are the 3 factors involved in maintaining hematopoietic stem cell pool?
3 factors needed to maintain Hematopoietic Stem Cells:
SCF
IL-3
BM stroma (Bone marrow stroma)
What causes differentiation of Hematopoietic stem cells to myeloid vs lymphoid precursor cells?
Hematopoitetic stem cell differentiation into Myeloid progenitor: SCF, IL3, GM-CSF
Hematopoitetic stem cell differentiation into Lymphoid progenitor: SCF, IL3, IL-7
What are the defects that can occur in hematopoiesis?
Hematopoietic stem cells are killed, replaced, or become malignant
What are the 3 types of Colony Stimulating Factors involved w/Hematopoietic Stem Cell differentiation? What do they bind to?
○ GM CSF = granulocyte macrophage colony stimulating factor
○ G CSF = granulocyte colony stimulating factor
○ M CSF = monocyte colony stimulating factor
They all bind to Kit receptor on the HSCs
What is Kit receptor? and what type of receptor is it? what does it do?
CD 117 = Kit receptor
Tyrosine kinase Type III receptor, sends signal to nucleus to activate HSC to survive, proliferate, and differentiate
receptor for stem cell growth factors (SCF) and colony stimulating factors (CSF)
What causes differentiation of Hematopoietic stem cells to erythrocytes vs megakaryocytes?
HSC to erythrocytes: EPO (erythropoietin)
HSC to megakaryocytes: TPO (thrombopoietin)
What are the 3 types of transient (acquired) defects in hematopoiesis?
Transient (acquired) hematopoietic defects
1) infection
2) maternal isoimmunization
3) premature birth, low # of RBCs
What is Fanconi anemia? inheritance? how does it present?
Fanconi anemia = aplastic anemia, affects all cell lines
Autosomal recessive
Chromosmal repair and stability proteins mutated
Presentation: short, strabismus, low set ears w/frequent infections +/- deafness, abnormal/absent thumbs
What is Diamond-Blackfan anemia? inheritance? how does it present?
Diamond Blackfan anemia = Erythrocyte mutation
Autosomal Dominant, and sporadic pedigrees
Defect in ribosome fx
Presentation: 50% have skeletal abnormalities, RBC aplasia, macrocytic anemia w/reticulocytopenia, snub nose
What is Kostmann syndrome? inheritance? how does it present?
Kostmann syndrome = neutrophil mutations
Autosomal Recessive
Mutation in G_CSF receptor
Presentation: predisposition to luekemia development and recurrent infections
What is Amegakaryocytic thrombocytopenia? inheritance?
Amegakaryocytic thrombocytopenia = megakarycyte mutation
Autosomal recessive and x-linked
What is Thrombocytopenia-absent radius (TAR) syndrome? how does it present?
Thrombocytopenia-absent radius (TAR) syndrome
presentation: Thrombocytopenia at birth, skeletal anomalies
What is the congenital hematopoietic defect that affects Erythrocyte development?
Diamond-Blackfan anemia
What is the congenital hematopoietic defect that affects Megakaryocyte development?
Amegakarocytic thrombocytopenia and Thrombocytopenia-absent Radius (TAR) syndrome
Order the WBCs from most numerous to least numerous
Never Let Monkeys Eat Bananas
Neutrophils > Lymphocytes»_space; Monocytes > Eosinophils > Basophils
Describe the order of development from hematopoeitc stem cell to erythrocyte
Which stage kicks out the mitochondria? the nucleus?
Which stage starts chromatin clumping?
HSC > myeloid precursor cell > Hemocytoblast > Proerythroblast > basophilic Erythroblast > Polychromatic erythroblast > Orthochromic erythroblast/Normoblast > Reticulocyte > Erythrocyte
Polychromatophilic erythroblast kicks out mitochondria
Orthochromic erythroblast/Normoblast kicks out nucleus to turn into Reticulocyte
Basophilic Erythroblasts start chromatin clumping
What is clinically significant about Basophilic Stippling of Erythrocytes?
What if there’s Howell-Jolly bodies?
Basophilic Stippling = toxic bone marrow injury IE megaloblastic anemia or lead poisoning (leads to lots of dots=condensed ribosomes/RNA)
Howell Jolly bodies = 1 or 2 dots, significant of spleen dysfunction or absence
What are Neutrophils significant for? why? (what do they do?) What interleukins are required for their differentiation?
What is a Left Shift in Neutrophils significant for? (what do they do?)
Where are most Neutrophils?
Neutrophils = acute bacterial infection, bc they phagocytize bacteria, debris, and dead tissue (collects and dies as pus) and degranulate
Need *IL6, GM-CSF, and *G-CSF to differentiate
Left shift = very sick person, marrow’s releasing immature neutrophils
Most neutrophils are in tissue
What are Eosinophils significant for? What do they do?What interleukins are required for their differentiation?
Eosinophils = allergies, parasite, cancer, bc they’re phagocytic for Ag-Ab complexes and neutrophils, attracted to inflammation sites by basophil/mast cell cytokines
Need *IL5, GM-CSF
Make inflammatory cytokines and granules, some break down our own tissue
What are basophils significant for? What do they do? What interleukins are required for their differentiation?
Basophils = maybe myeloproliferative disorders, inflammation, parasites, allergies… least common leukocyte
Need IL3, *IL4, GM-CSF to differentiate
Basophils enhance inflammation by arachidonic acid metabolite release, and release granules