[Preliminary study on biological printing of hBMSCs].
OBJECTIVE
To establish a two-dimensional biological printing technique of hBMSCs so as to control the cell transfer process and keep cell viability after printing.


METHODS
Bone marrow (5 mL) was obtained from healthy volunteer. The hBMSCs were regularly subcultured to harvest cells at passage 2, which were adjusted to the single cell suspension at a density of 1 x 10(6)/mL. The experiment was divided into 3 groups: printing group 1 in which cells underwent propidium iodide (PI) fluorescent labeling, then were transferred by rapid prototype biological printer (interval in x-axis 300 microm, interval in y-axis 1500 microm), and laser scanning confocal microscope was applied to observe cell fluorescence; printing group 2 in which cells received no PI labeling and were cultured for 2 hours after transfer, Live/Dead viability Kit was adopted to detect cell viability and laser scanning confocal microscope was applied to observe cell fluorescence; half of the cells in printing group receiving no Live/Dead viability Kit detection were cultured for 7 days, then inverted microscope was used to observe cell morphology, routine culture was conducted after the adherence of cells, the growth condition of cells was observed dynamically; control group in which steps were the same as the printing group 2 except that cell suspension received no printing.


RESULTS
Laser scanning confocal microscope observation on the cells in printing group 1 revealed the "cell ink droplets" were distributed regularly and evenly in the two-dimensional layer and each contained 15-35 cells, meeting the requirement of designing two-dimensional cell printing. The cells in printing group 2 went through cell viability test, laser scanning confocal microscope observation showed the fluorescence of cells 30 minutes after cell incubation. There was no significant difference between the control group and the printing groups in terms of cell viability. The printed cells presented normal adherence, good morphology and good growth state 7 days after routine culture.


CONCLUSIONS
Biological printing technique can realize the oriented, quantificational and regular distribution of hBMSCs in the two-dimensional plane and lays the foundation for the construction of three-dimensional cell printing or even organ printing system.
Ma
Sunxiang
S
Department of Plastic and Reconstructive Surgery, the Ninth People's Hospital, Medical College of Shanghai Jiaotong University, Shanghai, PR China.
Chai
Gang
G
Liu
Qihai
Q
Hu
Qingxi
Q
Zhou
Guangdong
G
Cui
Lei
L
D001854:Bone Marrow Cells / Q000166:cytology*; D018786:Bone Substitutes; D018929:Cell Culture Techniques / Q000379:methods*; D002469:Cell Separation; D002478:Cells, Cultured; D006801:Humans; D045164:Mesenchymal Stem Cell Transplantation; D010012:Osteogenesis; D023822:Tissue Engineering / Q000379:methods*
D018786:Bone Substitutes