BIO 447 Lecture Notes - Lecture 9: Selectin, Caspase, Monocyte
Document Summary
All blood cells arise from hematopoietic stem cells (hsc) self-renewing. Begins in embryonic yolk sac during first few weeks: stem cells primitive erythroid cells containing embryonic hemoglobin fetal liver/spleen (early hematopoiesis) bone marrow. Bone marrow | either become lymphoid progenitor cell or myeloid stem cell: controlled by amount/type of growth factors + cytokines, progenitor cell: lost capacity for self-renewal, committed to lineage. Hematopoietic cells grow/mature on meshwork of stromal cells non-hematopoietic cells that support growth/differentiation. Multi-specific | exert effects on a variety of cell targets, difficult to use as pharmaceutical agents can"t predict/control effects. Give mouse lethal dose of x-ray kills rbcs, generator cells mouse is immunosuppressed, dies in days/wks: give 200,000 mixed blood cells from matched donors. Survive because hematopoiesis (blood cell formation) is restored: give monoclonal antibodies specific for antigens on the surface of the differentiated wbcs. Survive, can be reconstituted with only 1,000 cells: remove already-committed early progenitor cells.
