7. Regeneration 1 Flashcards
Broad definition of repair in humans.
Combo of tissue regeneration and scar formation.
3 systems that undergo regeneration in the human body.
- Blood
- Skin
- GI tract
Component of the body that provides the scaffolding for tissue repair during fibrosis.
Extra-cellular Matrix
2 examples of physiologic proliferation of cells in the body.
- Endometrial cell proliferation stimulated by estrogen in the menstrual cycle.
- Thyroid gland growth under the influence of TSH
2 examples of pathologic proliferation of cells in the body.
- BPH
2. Thyroid Goiter
Name the 3 groups of tissues in the body based on proliferative activity.
- Labile Tissue - always dividing
- Quiescent - divides with a signal
- Non-dividing - arrested in G0 phase
Since neurons are non-dividing cells, how does the body repair and replace the damaged neurons?
Replaces with glial (neuronal support) cells.
Skeletal muscle cells that undergo slight differentiation and slight proliferative capacity.
Satellite Cells
Name and describe the 2 pathways that stem cells use to maintain the cell numbers.
- Obligatory Asymmetrical replication - one cell divides into 2 daughter cells. 1 Daughter cell differentiates while the other stays behind to divide again.
- Stochastic Differentiation - one cell divides into either two differentiating cells or two more dividing cells.
Term meaning that a cell can differentiate into any cell type in the body given the right stimulus.
Pluripotent
Term meaning that 1 cell can divide and differentiate into a whole multicellular organism.
Totipotent
Technique that can induce adult cells to become pluripotent.
Transfer a nucleus of a pluripotent cell into the cells of an adult so that damaged organs can be repopulated.
Explain transdifferentiation VS Metaplasia
Metaplasia - stimulus affects already differentiated cells to induce stem cell differentiation into another phenotype.
Transdifferentiation - stimulus affects already differentiated cells and these cells change phenotype.
3 sites where do hematopoietic stem cells come from?
- Bone Marrow
- Umbilical Cord
- Peripheral blood of pts. receiving cytokines
Multipotent cells that generate chondrocytes, osteoblasts, adipocytes, myoblasts, and endothelial cell precursors.
Marrow Stromal Cells
Bipotential progenitor cells of the liver capable of dividing into hepatocytes or biliary cells.
Oval Cells
Name 3 locations where stem cells reside in the skin.
- Interfollicular areas (right by hair follicle)
- Sebaceous glands
- Buldge area of hair follicle
Stem cells that maintain the cornea and reside at the junction of the cornea and the conjunctiva.
Limbal Stem cells
Restriction point of the cell cycle that checks the cell’s DNA before DNA replication.
G1/S checkpoint
3 proteins that regulate the G1/S checkpoint.
- Cyclins
- Cyclin-dependent Kinase (CDKs)
- CDK-Inhibitors
Checkpoint that monitors the DNA of cells after DNA replication.
G2/M checkpoint
Growth factor that is mitogenic for hepatocytes, epithelial cells, and fibroblasts.
Epidermal Growth Factor (EGF)
Growth factor that binds to the same receptor as EGF but is involved in malignant transformation of cells. Can be detected for cancer diagnosis.
Transforming Growth Factor-Alpha (TGF-A)
Growth factor with mitogenic effects on hepatocytes and most epithelial cells.
Hepatocyte Growth Factor or Scatter Factor
Growth factor that induces the migration and proliferation of fibroblasts, smooth muscle cells, and monocytes to areas of inflammation for tissue repair.
Platelet-Derived Growth Factor
Growth Factor that promotes angiogenesis and vasculogenesis (in fetuses).
Vascular Endothelial Growth Factor (VEGF)
Growth factor that contributes to hematopoiesis, angiogenesis, lung function, and formation of skeletal and cardiac muscles.
Fibroblast Growth Factor
Growth factor that stimulates fibroblast chemotaxis, enhances collagen production, and inhibits collagen degredation. Also contributes to fibrosis in chronic inflammation.
Transforming Growth Factor-Beta (and also Related Growth Factor)
2 cytokines involved in inflammation and wound healing.
- TNF
2. IL-1
2 cytokines involved in inflammation and initiating liver regeneration.
- TNF
2. IL-6
