Xenograft Decellularized Adipose Tissue Supports Adipose Remodeling In Rabbit

Background Decellularized adipose matrix(DAT)is a biological scaffold prepared by decellularization of adipose tissue.It provides a suitable microenvironment for adipose stem cells(ADSCs)and promotes their adipogenic differentiation which has good clinical application prospects.Soft tissue repair materials.In recent years,most studies have focused on allogeneic DAT,however,insufficient fat sources limit the wider application of allogeneic DAT.At present,whether xenotransplantation of DAT has adipogenic induction function,and the difference between the adipogenic ability and homologous DAT is still unclear.Therefore,in this study,the ability of xenogeneic DAT to induce fat regeneration was observed through in vitro and in vivo experiments,in order to explore the feasibility of xenogeneic DAT as an auxiliary material for tissue repair.Methods1.Decellularized adipose tissue derived from humans and rabbits was prepared by repeated freezing and thawing,trypsinization,oil extraction with isopropanol,and nucleic acid removal(Flynn’s classic method).The decellularization situation and the tissue structure after decellularization were analyzed by general comparison of the two DAT,H&E and DAPI staining.Extraction of human and rabbit ADSCs by enzymatic digestion and further cell culture,morphological observation,and detection of their osteogenic and adipogenic functions.2.Human ADSCs and rabbit ADSCs were extracted by enzymatic digestion,cell culture and morphology were observed,and their osteogenic and adipogenic functions were detected.3.Animal models of DAT transplantation were constructed with rabbits: allogeneic group(transplanted rabbit DAT),xenogeneic group(transplanted human DAT).The tissue structure,prognosis and the ability of adipogenesis of xenogeneic DAT were detected by H&E,Masson,CD31,Perilipin immunofluorescence and other methods,and compared with the allogeneic group.Results1.The DAT derived from human and rabbit was generally observed to be reduced in volume after decellularization,white jelly-like,and has a certain ductility.Histological examination showed no cellular structure of adipose tissue and negative nuclear staining,mainly composed of a large amount of collagen.The collagen structure of rabbit DAT was more dense.2.ADSCs from humans and rabbits are spindle-shaped or polygonal and grow adherently.The growth cloning ability of rabbit ADSCs was stronger than that of human ADSCs.The cytoskeleton immunofluorescence staining showed green fluorescently labeled cytoskeleton microfilament structure,and there was no obvious difference between the two cytoskeletons.Both ADSCs can differentiate into adipogenic and osteogenic cells after induction.3.In the absence of adipogenic induction medium,DAT in allogeneic group promoted the adipogenic differentiation function of ADSCs,and its adipogenic effect was consistent with that of DAT derived from allogeneic group.However,there was no significant difference between the allogeneic group DAT and the allogeneic group DAT on the proliferation and migration of adipose stem cells.4.The observed volume of xenogeneic DAT and allogeneic DAT decreased gradually after transplantation;H&E and Masson test could observe the adipose structure at the 2nd month after transplantation,and the adipose differentiation became more significant with time.In the early stage of transplantation,blood vessels with positive staining for CD31 can be seen.In the middle and late stages of transplantation,CD31 positive staining increased and perilipin positive adipocytes gradually appeared.The adipogenic function of xenogeneic DAT is basically the same as that of allogeneic DAT.Conclusion Xenogeneic DAT can induce fat regeneration,and its adipogenic ability has no statistical difference compared with allogeneic DAT.It is expected that xenografts can be achieved for soft tissue repair.