Objective: To study the influence of in vitro force-vascularization on in vivo vascularization of porous polylactic glycolic acid copolymer (PLGA) scaffolds with internal network channels (PPSINC).
Methods: After the in vitro force-vascularization of PPSINCs covered with microvessel endothelial cells (MVEC) of mice, they were divided into two groups: the force-vascularization group (group A) and the control group with only PSINCs (group B). All the PPSINCs were planted in the mesentery of 12 mice for 2 and 4 weeks, the PPSINCs were cut out, the vascularization of PPSINCs was investigated by histology and immunohistochemistry, and the vascularization area of the histologic section of the PPSINCs was measured with the computer-assistant image analysis system.
Results: After the in vitro force-vascularization of PPSINCs, the MVEC of the mice sticking on the channel wall could be seen. After the scaffold was implanted into the mice for 2 weeks, the vascularization area of the histologic section of PPSINCs (VA) in group A (2 260.91 +/- 242.35 microm2) was compared with that in group B (823.64 +/- 81.29 microm2), and the difference was significant in statistics (P < 0.01). The VA for 4 weeks in group A (17 284.36 +/- 72.67 microm2) was compared with that in group B (17 041.14 +/- 81.51 microm2), and the difference was not significant in statistics (P > 0.05). The area of the actin positive-staining (AA) in the histologic section of PPSINCs for 2 weeks' implantation in group A (565.22 +/- 60.58 microm2) was compared with that in group B (205.91 +/- 16.25 microm2), and the difference was significant in statistics (P < 0.01). After the implantation for 4 weeks, the VA in group A (4 321.09 +/- 19.82 microm2) was compared with group B (4 260.28 +/- 27.17 microm2), and the difference was not significant in statistics (P > 0.05).
Conclusion: The PPSINC is a good simple scaffold model of vascularization. The in vitro force-vascularization can increase the in vivo vascularization of PPSINCs in the early stage.