BD: Chondrocytes & Cartilage Flashcards
- What is cartilage?
a. Specialized connective tissue
- What makes cartilage regeneration limited?
a. Its avascular nature
- What are the three types of cartilage?
- Hyaline cartilage
- Elastic cartilage
- Fibrocartilage
- What collagen types make up hyaline cartilage?
a. 2 and 10
- Is hyaline cartilage the most abundant type of cartilage found in the body?
a. Yes
- Where is hyaline cartilage found?
a. Growth plates
b. Skeleton precursor
c. Joint articular surfaces
d. Costal cartilages
e. Nose, ears, trachea, larynx
What collagen type is found in elastic cartilage?
a. Type 2 collagen
- Where is elastic cartilage found?
a. Pharyngotympanic tubes
b. Epiglottis
c. Ear lobes
- What collagen type makes up fibrocartilage?
a. Type 1 collagen and hyaline cartilage type 2
- Where is fibrocartilage found at?
(PIT)
a. Pubic symphysis
b. IV discs
c. TMJ
- What do all osteoblasts, chondrocytes, myoblasts, and adipocytes start as before they differentiate?
a. Mesenchymal progenitor
What are the different zones of bone growth?
Mnemonic: Real, People, May, Have, Career, Options
a. Zone of reserve cartilage
b. Zone of proliferation
c. Zone of maturation
d. Zone of hypertrophy
e. Zone of degeneration/calcification
f. Zone of ossification
What is the principal engine for longitudinal bone growth?
a. Proliferation of columnar chondrocytes and expansion of chondrocyte size
What is the main master transcription factor in chondrocyte differentiation?
SOX9
What does SOX9 do to mesenchymal cells?
a. Turns them into chondrocytes and flat columnar chondrocytes
What turns flat columnar chondrocytes into terminal hypertrophic chondrocytes?
a. RUNX2
b. OSX
- Does SOX9 drive differentiation down the chondrocyte pathway?
Yes
- What cells express SOX9?
a. Chondroprogenitors and proliferating chondrocytes
In order for prehypertrophic and hypertrophic chondrocytes to proliferate, what must be down regulated?
SOX9
Does SOX9 inhibit RUNX2?
Yes
If Runx2 is deleted, what happens to chondrocyte?
They fail to mature
What collagen type do hypertrophic chondrocytes express?
Type 10
What do the chondrocytes express in order to allow for mineralization?
Alkaline phosphatases
What do the chondrocytes express in order to allow for vascular invasion to occur?
MMP13 and VEGF
What are the two ligands chondrocytes bind to?
PTHrP
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