TY - JOUR
T1 - Proteins Linked to a Protein Transduction Domain Efficiently Transduce Pancreatic Islets
AU - Embury, Jennifer
AU - Klein, Dagmar
AU - Pileggi, Antonello
AU - Ribeiro, Melina
AU - Jayaraman, Sundararajan
AU - Molano, R. Damaris
AU - Fraker, Christopher
AU - Kenyon, Norma
AU - Ricordi, Camillo
AU - Inverardi, Luca
AU - Pastori, Ricardo L.
PY - 2001/8
Y1 - 2001/8
N2 - The resounding success of a new immunosuppressive regimen known as the Edmonton protocol demonstrates that islet cell transplantation is becoming a therapeutic reality for diabetes. However, under the Edmonton protocol, a single donor does not provide enough islets to attain the insulin independence of a transplant recipient. This limitation is mainly caused by islet apoptosis triggered during isolation. In this study, we describe a highly efficient system of transiently transferring anti-apoptotic proteins into pancreatic islets, thus opening an exciting new therapeutic opportunity to improve the viability of transplantable islets. We fused β-galactosidase to the 11-amino acid residues that constitute the protein transduction domain (PTD) of the HIV/TAT protein and transduced pancreatic islets ex vivo with this fusion protein in a dose-dependent manner with >80% efficiency. We observed that transduction of the anti-apoptotic proteins Bcl-XL and PEA-15 fused to TAT/PTD prevented apoptosis induced by tumor necrosis factor-a in a pancreatic β-cell line, indicating that TAT/PTD anti-apoptotic proteins retained their biological activity. Finally, we demonstrated that TAT-fusion proteins did not affect the insulin secretion capability of islets, as determined by glucose static incubation and by reversion of hyperglycemia in diabetic immunodeficient mice.
AB - The resounding success of a new immunosuppressive regimen known as the Edmonton protocol demonstrates that islet cell transplantation is becoming a therapeutic reality for diabetes. However, under the Edmonton protocol, a single donor does not provide enough islets to attain the insulin independence of a transplant recipient. This limitation is mainly caused by islet apoptosis triggered during isolation. In this study, we describe a highly efficient system of transiently transferring anti-apoptotic proteins into pancreatic islets, thus opening an exciting new therapeutic opportunity to improve the viability of transplantable islets. We fused β-galactosidase to the 11-amino acid residues that constitute the protein transduction domain (PTD) of the HIV/TAT protein and transduced pancreatic islets ex vivo with this fusion protein in a dose-dependent manner with >80% efficiency. We observed that transduction of the anti-apoptotic proteins Bcl-XL and PEA-15 fused to TAT/PTD prevented apoptosis induced by tumor necrosis factor-a in a pancreatic β-cell line, indicating that TAT/PTD anti-apoptotic proteins retained their biological activity. Finally, we demonstrated that TAT-fusion proteins did not affect the insulin secretion capability of islets, as determined by glucose static incubation and by reversion of hyperglycemia in diabetic immunodeficient mice.
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U2 - 10.2337/diabetes.50.8.1706
DO - 10.2337/diabetes.50.8.1706
M3 - Article
C2 - 11473028
AN - SCOPUS:0035432970
VL - 50
SP - 1706
EP - 1713
JO - Diabetes
JF - Diabetes
SN - 0012-1797
IS - 8
ER -