·AIM: To investigate whether decellularization using different techniques can reduce immunogenicity of the cornea, and to explore the decellularized cornea as a scaffold for cultured corneal endothelial cells(CEC...·AIM: To investigate whether decellularization using different techniques can reduce immunogenicity of the cornea, and to explore the decellularized cornea as a scaffold for cultured corneal endothelial cells(CECs).Transplantation of decellularized porcine corneas increases graft transparency and survival for longer periods compared with fresh grafts.·METHODS: Six-month-old wild-type pig corneas were cut into 100-200 μm thickness, and then decellularized by three different methods: 1) 0.1% sodium dodecyl sulfate(SDS); 2) hypoxic nitrogen(N2); and 3) hypertonic NaCl. Thickness and transparency were assessed visually. Fresh and decellularized corneas were stained with hematoxylin/eosin(H&E), and for the presence of galactose-α1,3-galactose(Gal) and N-glycolylneuraminic acid(NeuGc, a nonGal antigen). Also, a human IgM/IgG binding assay was performed. Cultured porcine CECs were seeded on the surface of the decellularized cornea and examined after H&E staining.· RESULTS: All three methods of decellularization reduced the number of keratocytes in the stromal tissue by 】80% while the collagen structure remained preserved. No remaining nuclei stained positive for Gal or NeuGc, and expression of these oligosaccharides on collagen was also greatly decreased compared to expression on fresh corneas. Human IgM/IgG binding to decellularized corneal tissue was considerably reduced compared to fresh corneal tissue. The cultured CECs formed a confluent monolayer on the surface of decellularized tissue.· CONCLUSION: Though incomplete, the significant reduction in the cellular component of the decellularized cornea should be associated with a significantly reduced in vivo immune response compared to fresh corneas.展开更多
There is a critical shortage of organs, cells, and corneas from deceased human donors worldwide. There are also shortages of human blood for transfusion. A potential solution to all of these problems is the transplant...There is a critical shortage of organs, cells, and corneas from deceased human donors worldwide. There are also shortages of human blood for transfusion. A potential solution to all of these problems is the transplantation of organs, cells, and corneas from a readily available animal species, such as the pig, and the transfusion of red blood cells from pigs into humans. However, to achieve these ends, major immunologic and other barriers have to be overcome. Considerable progress has been made in this respect by the genetic modification of pigs to protect their tissues from the primate immune response and to correct several molecular incompatibilities that exist between pig and primate. These have included knockout of genes responsible for the expression of major antigenic targets for primate natural anti-pig antibodies, insertion of human complement- and coagulation-regulatory transgenes, and knockdown of swine leukocyte antigens that stimulate the primate＇s adaptive immune response. As a result of these manipulations, the administration of novel immunosuppressive agents, and other innovations, pig hearts have now functioned in baboons for 6-8 months, pig islets have maintained normoglycemia in diabetic monkeys for 〉 1 year, and pig corneas have maintained transparency for several months. Clinical trials of pig islet trans- plantation are already in progress. Future developments will involve further genetic manipulations of the organ- source pig, with most of the genes that are likely to be beneficial already identified.展开更多
Over the past several decades,significant scientific progress in xenotransplantation has brought the field to the threshold of clinical trials.In the past 3 years in the United States,experimental pig kidney and heart...Over the past several decades,significant scientific progress in xenotransplantation has brought the field to the threshold of clinical trials.In the past 3 years in the United States,experimental pig kidney and heart xenotransplantation have been performed on human subjects recently declared dead by neurological criteria(decedents).In addition,two pig heart transplants have been carried out in living patients under the United States Food and Drug Administration's expanded access guidelines.However,though there has been a flurry of activity there remain unanswered questions regarding how the public views xenotransplantation,what concerns may exist,and how to address these concerns in a meaningful way.This paper aims to underscore the importance of public engagement in xenotransplantation,emphasizing the ongoing need for studies to assess public opinions.The current evidence on public engagement studies is reviewed and gaps in our understanding are identified.We propose practical steps to advance this field.Additional studies to determine the extent of racial/ethnic differences in attitudes to xenotransplantation should be conducted.Empirical and descriptive analysis of certain religious viewpoints—especially minority faiths—would be valuable.As public engagement is an important aspect of public acceptance of novel research that is accompanied by risk,we suggest that xenotransplantation biotechnology companies might consider leading the way in funding this research.展开更多
There has been a continuing inadequate number of human organs for the treatment of patients with terminal organ failure worldwide.The transplantation of organs from genetically engineered pigs may prove an alternative...There has been a continuing inadequate number of human organs for the treatment of patients with terminal organ failure worldwide.The transplantation of organs from genetically engineered pigs may prove an alternative solution[1].In recent years,great progress has been made in pig-to-nonhuman primate(NHP)organ transplantation models(Table S1 online).展开更多
基金Supported in part by NIH Grants#1RO3A 1096296-01 (HH), #IU19A1090959-01 (DKCC), #U01A 1066331 (DKCC), and #5P01 HL107152-02 (DKCC)Ocular Tissue Engineering and Regenerative Ophthalmology (OTERO) Postdoctoral Fellowship (WL)Sponsored Research Agreements Between the University of Pittsburgh and Revivicor, Blacksburg, VA
文摘·AIM: To investigate whether decellularization using different techniques can reduce immunogenicity of the cornea, and to explore the decellularized cornea as a scaffold for cultured corneal endothelial cells(CECs).Transplantation of decellularized porcine corneas increases graft transparency and survival for longer periods compared with fresh grafts.·METHODS: Six-month-old wild-type pig corneas were cut into 100-200 μm thickness, and then decellularized by three different methods: 1) 0.1% sodium dodecyl sulfate(SDS); 2) hypoxic nitrogen(N2); and 3) hypertonic NaCl. Thickness and transparency were assessed visually. Fresh and decellularized corneas were stained with hematoxylin/eosin(H&E), and for the presence of galactose-α1,3-galactose(Gal) and N-glycolylneuraminic acid(NeuGc, a nonGal antigen). Also, a human IgM/IgG binding assay was performed. Cultured porcine CECs were seeded on the surface of the decellularized cornea and examined after H&E staining.· RESULTS: All three methods of decellularization reduced the number of keratocytes in the stromal tissue by 】80% while the collagen structure remained preserved. No remaining nuclei stained positive for Gal or NeuGc, and expression of these oligosaccharides on collagen was also greatly decreased compared to expression on fresh corneas. Human IgM/IgG binding to decellularized corneal tissue was considerably reduced compared to fresh corneal tissue. The cultured CECs formed a confluent monolayer on the surface of decellularized tissue.· CONCLUSION: Though incomplete, the significant reduction in the cellular component of the decellularized cornea should be associated with a significantly reduced in vivo immune response compared to fresh corneas.
文摘There is a critical shortage of organs, cells, and corneas from deceased human donors worldwide. There are also shortages of human blood for transfusion. A potential solution to all of these problems is the transplantation of organs, cells, and corneas from a readily available animal species, such as the pig, and the transfusion of red blood cells from pigs into humans. However, to achieve these ends, major immunologic and other barriers have to be overcome. Considerable progress has been made in this respect by the genetic modification of pigs to protect their tissues from the primate immune response and to correct several molecular incompatibilities that exist between pig and primate. These have included knockout of genes responsible for the expression of major antigenic targets for primate natural anti-pig antibodies, insertion of human complement- and coagulation-regulatory transgenes, and knockdown of swine leukocyte antigens that stimulate the primate＇s adaptive immune response. As a result of these manipulations, the administration of novel immunosuppressive agents, and other innovations, pig hearts have now functioned in baboons for 6-8 months, pig islets have maintained normoglycemia in diabetic monkeys for 〉 1 year, and pig corneas have maintained transparency for several months. Clinical trials of pig islet trans- plantation are already in progress. Future developments will involve further genetic manipulations of the organ- source pig, with most of the genes that are likely to be beneficial already identified.
文摘Over the past several decades,significant scientific progress in xenotransplantation has brought the field to the threshold of clinical trials.In the past 3 years in the United States,experimental pig kidney and heart xenotransplantation have been performed on human subjects recently declared dead by neurological criteria(decedents).In addition,two pig heart transplants have been carried out in living patients under the United States Food and Drug Administration's expanded access guidelines.However,though there has been a flurry of activity there remain unanswered questions regarding how the public views xenotransplantation,what concerns may exist,and how to address these concerns in a meaningful way.This paper aims to underscore the importance of public engagement in xenotransplantation,emphasizing the ongoing need for studies to assess public opinions.The current evidence on public engagement studies is reviewed and gaps in our understanding are identified.We propose practical steps to advance this field.Additional studies to determine the extent of racial/ethnic differences in attitudes to xenotransplantation should be conducted.Empirical and descriptive analysis of certain religious viewpoints—especially minority faiths—would be valuable.As public engagement is an important aspect of public acceptance of novel research that is accompanied by risk,we suggest that xenotransplantation biotechnology companies might consider leading the way in funding this research.
基金supported by the National Natural Science Foundation of China(81900571,81870446,and 82070671)the National Institutes of Health/National Institute of Allergy and Infectious Diseases U19 of USA(AI090959)。
文摘There has been a continuing inadequate number of human organs for the treatment of patients with terminal organ failure worldwide.The transplantation of organs from genetically engineered pigs may prove an alternative solution[1].In recent years,great progress has been made in pig-to-nonhuman primate(NHP)organ transplantation models(Table S1 online).
