ICS-Heme-Hematopoiesis & BM Failure
Terms
undefined, object
copy deck
- basophils?
-
1.neutrotransmitters
2.mast cell precursor
3.vasoactive amines - NK cells?
- viral imm (b/c kill the whole cell, and viruses usually intracellular)
- process of hematopoiesis req:
-
1.stem cell pool
2.hematopoetic cytokines
3.stroma (supportive environ)
4.nutrients - PHSC's (pluripotent hematopoietic stem cells) express what antigen?
- ONLY CD34 (this is lost as cells differentiate)
- what properties do PHSC's have?
-
1.self renewal
2.differentiation -
-what are the earliest sites of PHSC prolif and differentiation?
-when and where do they appear? -
blood islands
-appear at 6 wks in the yolk sac - what happens after blood islands? during what time period
- -cells migrate from yolk sac to liver and spleen, where organ hemotopoiesis occurs thru 15th wk gestation
- desc embryology of hematopoiesis
-
A. 6 wks: blood islands (earliest site of PHSC prolif and differentiation) appear in yolk sac.
B. 6 wks-15 wks: PSCSs in liver and spleen (organ hematopoiesis)
C. 15 wks: BM (primary site of blood cell production thru remainder of gestation and post-birth life) - what dio PHSC's arise from?
- mesenchymal tissue
- extramedullary hematopoiesis
-
=heamtopoiesis outside the BM
-in times of stress (i.e. CML), liver and spleen become HUGE b/c they revert to blood-forming organs - what drives differentiation of PHSC's?
-
hematopoietic cytokines (hormones that regulate blodo cell production)
AND many cytokines are promiscuous (act on >1 lineage at >1 level of hematopoiietic development, i.e. IL3) -
what is leukoerythroblastic rxn?
what does this suggest? -
presence of immature WBC's and nucleated RBC's
-suggests infiltrative process in BM - tear-drop RBC's
- suggests infiltrative process in BM (metastatic tumor, fibrosis, granuloma)
- hypercellular BM and peripheral cytopenia
- myelodysplastic syndrome (a "premalignant" condition)
- first sign of BM failure
- pancytopenia