Lecture 3: MSC-Derived Connective Tissue Flashcards
Mesenchymal stem cell
Progenitor for all resident tissue cells, differentiates from ESC
Basic components of all connective tissue
- Cells
- Fibers
- Ground substance
Extracellular matrix
Composed of all extracellular parts of connective tissue (fibers + ground substance)
Type II collagen
Primary part of hyaline cartilage. Very tight, hydrated ECM that makes cell motility impossible.
Type I collagen
Dominant large fiber of CT. Forms ropes/sheets for structural and space-filling roles as procollagen linked into fibrils. More type I = more density
Hydrogels
Bioengineered compounds that mimic CT properties
Mesenchymal stem cell
Progenitor cell for all stromal cells of CT compartments (adipocytes, fibroblasts, muscle)
Unilocular adipocytes
Also known as white fat cells occur in white adipose tissue and primarily act as energy storage. Will often undergo hypertrophy instead of dividing.
Multilocular adipocytes
Also known as brown fat cells, occurring in brown adipose tissue. Specialized for thermogenesis.
Beige fat cells
Transitional stage between from white fat to brown fat. Multilocular thermogenic cells found in white adipose tissue
Fat depots
Areas of white fat collections, e.g. the subcutaneous, visceral, and intermuscular fat.
Fibroblasts
Cells responsible for production, remodeling, and degradation of ECM fibers and ground substance
Myofibroblasts
Myosin-producing fibroblast subtype. Responsible for generating force, e.g. in wound closure
Type III collagen
Dominant small fiber of CT and in the mesenchyme (embryonic undifferentiated CT). Provides support in regions with more cells. More type III vs type I typically makes looser CT. AKA reticular fibers
Elastin
Main protein in elastic fibers, along with some fibrillins. Provide stretchiness in CT.
Type IV collagen
Forms the lamina densa of external/basement membranes
Type VII collagen
Forms anchoring filaments in lamina reticularis of external/basement membranes