The cornea is a highly specialized and unique organ in the human body. Its main function is to project light from the external environment onto the retina, and it has a specific transparency to perform its function pr...The cornea is a highly specialized and unique organ in the human body. Its main function is to project light from the external environment onto the retina, and it has a specific transparency to perform its function properly. The transparency and integrity of the cornea is of vital importance. The corneal wound, especially laceration deep to Bowman＇s membrane and stroma, which will inevitably cause scar formation, may cause the degeneration or even loss of sight.展开更多
Background:Corneal stromal stem cells(CSSC)reduce corneal inflammation,prevent fibrotic scarring,and regenerate transparent stromal tissue in injured corneas.These effects rely on factors produced by CSSC to block the...Background:Corneal stromal stem cells(CSSC)reduce corneal inflammation,prevent fibrotic scarring,and regenerate transparent stromal tissue in injured corneas.These effects rely on factors produced by CSSC to block the fibrotic gene expression.This study investigated the mechanism of the scar-free regeneration effect.Methods:Primary human CSSC(hCSSC)from donor corneal rims were cultivated to passage 3 and co-cultured with mouse macrophage RAW264.7 cells induced to M1 pro-inflammatory phenotype by treatment with interferonγand lipopolysaccharides,or to M2 anti-inflammatory phenotype by interleukin-4,in a Transwell system.The timecourse expression of human transforming growth factorβ3(hTGFβ3)and hTGFβ1 were examined by immunofluorescence and qPCR.TGFβ3 knockdown for>70%in hCSSC[hCSSC-TGFβ3(si)]was achieved by small interfering RNA transfection.Naïve CSSC and hCSSC-TGFβ3(si)were transplanted in a fibrin gel to mouse corneas,respectively,after wounding by stromal ablation.Corneal clarity and the expression of mouse inflammatory and fibrosis genes were examined.Results:hTGFβ3 was upregulated by hCSSC when co-cultured with RAW cells under M1 condition.Transplantation of hCSSC to wounded mouse corneas showed significant upregulation of hTGFβ3 at days 1 and 3 post-injury,along with the reduced expression of mouse inflammatory genes(CD80,C-X-C motif chemokine ligand 5,lipocalin 2,plasminogen activator urokinase receptor,pro-platelet basic protein,and secreted phosphoprotein 1).By day 14,hCSSC treatment significantly reduced the expression of fibrotic and scar tissue genes(fibronectin,hyaluronan synthase 2,Secreted protein acidic and cysteine rich,tenascin C,collagen 3a1 andα-smooth muscle actin),and the injured corneas remained clear.However,hCSSC-TGFβ3(si)lost these anti-inflammatory and anti-scarring functions,and the wounded corneas showed intense scarring.Conclusion:This study has demonstrated that the corneal regenerative effect of hCSSC is mediated by TGFβ3,inducing a scar-free tissue response.展开更多
基金THIS STUDY WAS SUPPORTED BY A GRANT FROM THE NATIONAL NATURAL SCIENCE FOUNDATION OF CHINA (NO. 30571997) AND SHANDONG SCIENTIFIC AND TECHNOLOGICAL COMMITTEE.
文摘The cornea is a highly specialized and unique organ in the human body. Its main function is to project light from the external environment onto the retina, and it has a specific transparency to perform its function properly. The transparency and integrity of the cornea is of vital importance. The corneal wound, especially laceration deep to Bowman＇s membrane and stroma, which will inevitably cause scar formation, may cause the degeneration or even loss of sight.
基金This work was supported by the Department of Defence Grant W81WH-19-1-0778(JLF,YD),NIH Grants RO1 EY016415(JLF)and P30 EY008098(JLF),Stein Innovator Award from Research to Prevent Blindness(JLF),Eye and Ear Foundation of Pittsburgh,and Louis J Fox Centre for Vision Restoration.
文摘Background:Corneal stromal stem cells(CSSC)reduce corneal inflammation,prevent fibrotic scarring,and regenerate transparent stromal tissue in injured corneas.These effects rely on factors produced by CSSC to block the fibrotic gene expression.This study investigated the mechanism of the scar-free regeneration effect.Methods:Primary human CSSC(hCSSC)from donor corneal rims were cultivated to passage 3 and co-cultured with mouse macrophage RAW264.7 cells induced to M1 pro-inflammatory phenotype by treatment with interferonγand lipopolysaccharides,or to M2 anti-inflammatory phenotype by interleukin-4,in a Transwell system.The timecourse expression of human transforming growth factorβ3(hTGFβ3)and hTGFβ1 were examined by immunofluorescence and qPCR.TGFβ3 knockdown for>70%in hCSSC[hCSSC-TGFβ3(si)]was achieved by small interfering RNA transfection.Naïve CSSC and hCSSC-TGFβ3(si)were transplanted in a fibrin gel to mouse corneas,respectively,after wounding by stromal ablation.Corneal clarity and the expression of mouse inflammatory and fibrosis genes were examined.Results:hTGFβ3 was upregulated by hCSSC when co-cultured with RAW cells under M1 condition.Transplantation of hCSSC to wounded mouse corneas showed significant upregulation of hTGFβ3 at days 1 and 3 post-injury,along with the reduced expression of mouse inflammatory genes(CD80,C-X-C motif chemokine ligand 5,lipocalin 2,plasminogen activator urokinase receptor,pro-platelet basic protein,and secreted phosphoprotein 1).By day 14,hCSSC treatment significantly reduced the expression of fibrotic and scar tissue genes(fibronectin,hyaluronan synthase 2,Secreted protein acidic and cysteine rich,tenascin C,collagen 3a1 andα-smooth muscle actin),and the injured corneas remained clear.However,hCSSC-TGFβ3(si)lost these anti-inflammatory and anti-scarring functions,and the wounded corneas showed intense scarring.Conclusion:This study has demonstrated that the corneal regenerative effect of hCSSC is mediated by TGFβ3,inducing a scar-free tissue response.
