Delivering MC3T3-E1 cells into injectable calcium phosphate cement through alginate-chitosan microcapsules for bone tissue engineering.
OBJECTIVE
To deliver cells deep into injectable calcium phosphate cement (CPC) through alginate-chitosan (AC) microcapsules and investigate the biological behavior of the cells released from microcapsules into the CPC.


METHODS
Mouse osteoblastic MC3T3-E1 cells were embedded in alginate and AC microcapsules using an electrostatic droplet generator. The two types of cell-encapsulating microcapsules were then mixed with a CPC paste. MC3T3-E1 cell viability was investigated using a Wst-8 kit, and osteogenic differentiation was demonstrated by an alkaline phosphatase (ALP) activity assay. Cell attachment in CPC was observed by an environment scanning electron microscopy.


RESULTS
Both alginate and AC microcapsules were able to release the encapsulated MC3T3-E1 cells when mixed with CPC paste. The released cells attached to the setting CPC scaffolds, survived, differentiated, and formed mineralized nodules. Cells grew in the pores concomitantly created by the AC microcapsules in situ within the CPC. At Day 21, cellular ALP activity in the AC group was approximately four times that at Day 7 and exceeded that of the alginate microcapsule group (P<0.05). Pores formed by the AC microcapsules had a diameter of several hundred microns and were spherical compared with those formed by alginate microcapsules.


CONCLUSIONS
AC microcapsule is a promising carrier to release seeding cells deep into an injectable CPC scaffold for bone engineering.
Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing 100081, China; Beijing Key Lab of Fine Ceramics, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China; Department of Preventive Dentistry, Peking University School and Hospital of Stomatology, Beijing 100081, China; National Engineering Laboratory for Digital and Material Technology of Stomatology, Peking University School and Hospital of Stomatology, Beijing 100081, China.
Peng-yan
PY
Qiao
Fang-fang
FF
Li
Li-min
LM
Dong
Tao
T
Xu
Qiu-fei
QF
Xie
D016475:3T3 Cells; D000464:Alginates; D000818:Animals; D001843:Bone Cements; D016025:Bone Transplantation / Q000379:methods; D002113:Calcification, Physiologic; D002130:Calcium Phosphates; D002214:Capsules; D002448:Cell Adhesion; D002454:Cell Differentiation; D002470:Cell Survival; D048271:Chitosan; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D051379:Mice; D008855:Microscopy, Electron, Scanning; D010006:Osteoblasts / Q000166:cytology / Q000637:transplantation*; D010012:Osteogenesis; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry
D000464:Alginates; D001843:Bone Cements; D002130:Calcium Phosphates; D002214:Capsules; D006603:Hexuronic Acids; D020723:Glucuronic Acid; D048271:Chitosan; C020243:calcium phosphate