CARTILAGE

 

Cartilage is a firm, but flexible, connective tissue made of chondrocytes. These specialized cells secrete large amounts of extracellular matrix (ECM) mainly composed of collagen, elastin fibers, and proteoglycans. There are three different types of cartilage, which secrete different amounts of ECM and are found in different areas around the body. Hyaline class cartilage, which is found between joints, is flexible, supports heavy loads, and distributes weight.

 

Many researchers focus on hyaline class cartilage because as a result of its avascularity, it regenerates poorly. Cartilage damage is a continual degradation which leads to severe pains and even disability.

 

Again, autologous chondrocytes are the best choice for engineering cartilage of this type, however, chondrocytes can only be acquired through invasive techniques; furthermore, the isolated cells will dedifferentiate into fibroblasts when in a monolayer culture. Alternate sources like MSCs are now being studied because of the regressive nature of chondrocytes and the method of which they are harvested. 

 

Natural and synthetic scaffolds have been used to study application of cartilage tissue engineering. PEG, elastin based polymers, self-assembling peptides, collagen, fibrin, alginate are commonly studied scaffold materials. Scientists are continuing research to find the optimal material which aids in chondrocyte proliferation yet fulfills the job to evenly distribute weight.

 

The future of cartilage TE is focused on integration of cartilage constructs in vivo with native host tissues. Immediate implantation should allow for the scaffold to maintain shape while accomplishing its mechanical role in the human body.

 

W8.1, W8.2