Study On The Hypertrophic Scar Animal Moedl Of Severe Combined Immuno Deficiency Mice

Objective To establish a new type of hypertrophic scar(HS)model on severe combined immunodeficiency mice(SCID mice)and study the characteristics of morphology and histology and investigate the feasibility.Methods Human split-thickness skin graft was transplanted onto the dorsum of SCID mice(n=30)and was observed weekly,the harvested xenograft was then assessed and biopsied for histology by hematoxylin & eosin(H&E)or Masson's trichrome staining for the microscopic levels and the collagen structure.Hydroxyproline quantification was then performed by colorimetry to dominate the collagen levels and immunohistochemical staining for CD163 positive and ?-SMA for detecting the levels of macrophages and myofibroblasts.Real-time polymerase chain reaction(RT-PCR)analysis was also performed to identify m RNA levels of transforming growth factor-?1(TGF-?1),connective tissue growth factor(CTGF)and ?-smooth muscle actin(?-SMA).Results The xenograft showed a characteristic of human HS including a red,firm,elevated appearance,increase in thickness,changed adnexal structures,hypervascularization,thinner collagen fibrils and disorganization of them.The content of hydroxyproline increased compared to the control group.Macrophages showed a relative augment pattern in xenograft tissues.Moreover,RT-PCR showed significantly elevated m RNA levels for TGF-?1,CTGF and ?-SMA.Conclusion Above features of the xenograft demonstrated this animal model having intrinsic properties that closely resemble HS formation as seen in humans,which shares additional merits of simple operation and flexible controllability and therefore can be expected to play a critic role in the research of human HS.