OBJECTIVEBy observing the adipogenic and angiogenic microenvironment impact on the morphology of newly generated tissue for exploring the key factors which inducing mature adipose tissue regeneration in tissue engineering model.

METHODS24 healthy 6 months' New Zealand rabbits were picked and put into four groups according to different microenvironment. Every group has 6 rabbits and divided as follows: no axial-blood supply fat flap(0 ml), granular fat only(0.6 ml), axial blood vessel only (0.05 ml), axial vascularized fat flap ((0.6 ml). We separated or combined adipogenic and angiogenic environment within these groups. After 8 weeks, samples were harvested for histologic observation including macroscopic observation, volume analysis and HE testing.

RESULTSIn granular fat group, its volume decreased by (0.25 ± 0.10) ml after 8 weeks as the shortage of blood supply and finally it could be enveloped. In axial blood vessel group, its volume increased by (0. 37 ± 0. 04) ml after 8 weeks with fibrous tissue formation as shortage of adipogenic microenvironment. The no axial-blood supply fat flap group grew into(0.12 ± 0.03) ml, which can' t support large volume adipose tissue formation because of lacking independent blood supply. Only axial vascularized fat flap model could generate mature adipose tissue in large volume(3.45 ± 0.48) ml. The number of new capillary in every group was different after 8 weeks. By counting the numbers in every single view, no axial-blood supply fat flap group 15 ± 3.5)and granular fat only group(5 ± 2.5)had a significant difference with axial vascularized fat flap group 22 ± 5) respectively.

CONCLUSIONOnly both adipogenic or angiogenic microenvironment exist could induce mature adipose tissue in large volume in tissue engineering chamber model.