Lecture 1

Question 1

WHAT VERTEBRATE REPRESENTS THE “GOLD STANDARD” OF REGENERATION

Answer 1

SALAMANDER*

*THEY ARE THE ONLY VERTEBRATE CAPABLE OF REGROWING LOST LIMBS

Question 2

LIMB REGENERATION

Answer 2

1. ) WOUND CLOSURE - EPIDERMAL SKIN CELLS MIGRATE ACROSS SKIN CELLS TO CLOSE WOUND
2. ) HEALING SIGNALS - EPIDERMAL CELLS YIELD AN APICAL EPITHELIAL CAP (CELL RIDGE) WHICH GENERATES SIGNALS TO GUIDE BEHAVIOR OF OTHER CELLS (I.E. FIBROBLASTS MIGRATE TO THE WOUND SITE)
3. ) MIGRATED CELLS YIELD LESS SPECIALIZED EMBRYONIC STATE AND START DIVIDING TO POPULATE BUD OF A NEW LIMB (BLASTEMA - LIMB BUD)
4. ) BLASTEMA GROWS - YIELDS A LIMB SHAPE AND EMBRYONIC CELLS CONTINUE TO DIFFERENTIATE INTO BONE AND FIBROBLASTS AND OTHER TISSUE
5. ) LIMB LENGTHENS TO RESEMBLE AMPUTATED LIMB

Question 3

REGENERATION VS. REPAIR

Answer 3

REGENERATION - MOST FAVORABLE OUTCOME - REPLACES OLD W/ NEW AND ENDS WITH THE EXACT SAME STRENGTH AND CAPABILITIES
**REQUIRES INTACT CONNECTIVE TISSUE
REPAIR - RESTORATION OF DAMAGED TISSUE - DOES NOT END W/SAME STRENGTH OR CAPABILITIES (REPAIR IS A COMBINATION OF REGENERATION AND SCAR FORMATION BY DEPOSITION OF COLLAGEN)

Question 4

2 TYPES OF REGENERATION

Answer 4

1. ) RENEWING TISSUES - COMPLETE
   * *GI TRACT EPITHELIUM, HEMATOPOIETIC SYSTEM, EPIDERMIS
2. ) STABLE TISSUES - COMPENSATORY GROWTH OF MISSING TISSUE FROM PRESENT TISSUE
   * *LIVER/KIDNEY TRANSPLANTS

Question 5

2 TYPES OF REPAIR

Answer 5

1. ) WOUND HEALING/SCAR FORMATION

2. ) CHRONIC INFLAMMATION - INJURY YIELDS REPAIR WHICH RESULTS IN FIBROSIS (THICKENING/SCARRING OF CONNECTIVE TISSUE)

Question 6

3 TYPES OF STEM CELLS USED IN REGENERATION

Answer 6

1. ) EMBRYONIC STEM CELLS
2. ) ADULT STEM CELLS
3. ) INDUCED PLURIPOTENT STEM CELLS

Question 7

EMBRYONIC STEM CELLS

Answer 7

REQUIRE SPECIFIC SIGNALS TO DIFFERENTIATE

THEY HAVE UNLIMITED EXPANSION CAPABILITIES AND PLURIPOTENCY

Question 8

ADULT STEM CELLS

Answer 8

MAINTAIN AND REPAIR TISSUE IN WHICH THEY ARE FORMED (THEY ARE UNDIFFERENTIATED STEM CELLS FOUND AMONG DIFFERENTIATED TISSUE)
SELF RENEWABLE - FOUND IN BONE MARROW, PLACENTA, FAT)

Question 9

INDUCED PLURIPOTENT STEM CELLS

Answer 9

SOMATIC CELLS GENETICALLY REPROGRAMMED TO AN EMBRYONIC STEM CELL-LIKE STATE

Question 10

STEM CELL SOURCES

Answer 10

1.) MESENCHYMAL STEM CELLS - MULTIPOTENT STROMAL CELLS (DERIVED FROM BONE MARROW) (=> ASC)
HAVE THE ABILITY TO DIFFERENTIATE INTO OSTEOBLASTS, CHONDROCYTES, ADIPOCYTES
2.) FIBROBLASTS - GENETICALLY REPROGRAMMED TO EMBRYONIC STEM CELLS-LIKE STATE (=> IPSC)
3.) BLASTOCYTES - EMBRYONIC STEM CELLS ARE ISOLATED FROM THE INNER CELL MASS OF BLASTOCYTES (=> ESC)

Question 11

BONE DEFECT THERAPY W/ STEM CELLS

Answer 11

1. ) SEGMENTAL BONE DEFECT OCCURS
2. ) COLLAGEN SCAFFOLD IMPLANTED TO SITE
3. ) ENDOGENOUS MSCs INVADE SCAFFOLD
4. ) BMP GENE INJECTED INTO SITE OF SCAFFOLD
5. ) ULTRASOUND PULSE APPLIED MAKES DNA BE UPTAKEN BY MSCs AND BMP SECRETION CAUSES FRACTURE REPAIR

Question 12

PULP REGENERATION USING SCAPs

Answer 12

1. ) PULPITIS
2. ) PULPOTOMY
3. ) INJECTION OF PULP CHAMBER W/ SCAP, GRANULOCYTE COLONY-STIMULATING FACTOR (G-CSF), SCAFFOLD
4. ) PULP REGENERATION

Question 13

ECM

Answer 13

LOADED W/ STEM CELLS (I.E. MOSTLY PROTEINS AND HELPS MAINTAIN CELLS IN THEIR PROPER PLACE)