posted on 2021-04-29, 15:09authored byYanbing Shen, Yong Xu, Bingcheng Yi, Xianliu Wang, Han Tang, Chang Chen, Yanzhong Zhang
Engineering
scaffolds with structurally and biochemically biomimicking
cues is essential for the success of tissue-engineered cartilage.
Chitosan (CS)-based scaffolds have been widely used for cartilage
regeneration due to its chemostructural similarity to the glycosaminoglycans
(GAGs) found in the extracellular matrix of cartilage. However, the
weak mechanical properties and inadequate chondroinduction capacity
of CS give rise to compromised efficacy of cartilage regeneration.
In this study, we incorporated short fiber segments, processed from
electrospun aligned poly(lactic-co-glycolic acid)
(PLGA) fiber arrays, into a citric acid-modified chitosan (CC) hydrogel
scaffold for mechanical strengthening and structural biomimicking
and meanwhile introduced cartilage-decellularized matrix (CDM) for
biochemical signaling to promote the chondroinduction activity. We
found that the incorporation of PLGA short fibers and CDM remarkably
strengthened the mechanical properties of the CC hydrogel (+349% in
compressive strength and +153% in Young’s modulus), which also
exhibited a large pore size, appropriate porosity, and fast water
absorption ability. Biologically, the engineered CDM-Fib/CC scaffold
significantly promoted the adhesion and proliferation of chondrocytes
and supported the formation of matured cartilage tissue with a cartilagelike
structure and deposition of abundant cartilage ECM-specific GAGs and
type II collagen (+42% in GAGs content and +295% in type II collagen
content). The enhanced mechanical competency and chondroinduction
capacity with the engineered CDM-Fib/CC scaffold eventually fulfilled
successful in situ osteochondral regeneration in
a rabbit model. This study thereby demonstrated a great potential
of the engineered highly biomimetic chitosan-based scaffold in cartilage
tissue repair and regeneration.