Contributions
Abstract: EP1592
Type: Poster Sessions
Abstract Category: Therapy - Immunomodulation/Immunosuppression
Background: The development of safer and more efficient immune therapies remains an important unmet medical need in patients with autoimmune diseases. Induction of antigen-specific immune tolerance can be achieved via injection of cells chemically coupled with target antigens. Preclinical studies with peptide-coupled splenocytes have suggested cross-tolerance“ as the main mechanism of action for inducing tolerance (1), whereby peptide-coupled cells undergo apoptosis and are processed by macrophages in the spleen to represent the antigens in a tolerogenic way. Much less is known using peptide-coupled red blood cells (RBCs) instead of peptide coupled splenocytes.
Goals: Objectives of this project are to analyze the effects of the coupling procedure on RBCs in vitro and investigate the biodistribution of peptide-coupled RBCs in vivo.
Methods and Results: Treatment with the cross-linker ethylcarbodiimide (EDC) led to a reduced deformability of peptide-coupled RBCs as observed by ektacytometry. Electron microscopy analysis revealed only minor morphological changes following treatment with EDC.
In addition, coupling of RBCs initiates physiological changes such as a rapid influx of cytosolic calcium and phosphatidylserine exposure, both hallmarks of programmed cell death in RBCs, called eryptosis.
Both deformability and morphological changes of peptide-coupled RBCs appear to influence the in vivo biodistribution and direct these cells to specific organs. To identify the cellular origin involved in the uptake of peptide-coupled RBCs, we injected fluorescently-labelled peptides coupled to RBCs intravenously in BALB/c mice and analysed the biodistribution, both in vivo and ex vivo. Bioluminiscence imaging data indicates the liver as one of the major organs involved in the uptake of peptide-coupled RBCs. Histological analysis confirmed the aforementioned findings, demonstrating uptake of peptide-coupled RBCs by liver macrophages/Kupffer cells.
Conclusion: RBCs exhibit hallmark characteristics of eryptosis following peptide coupling and these are efficiently taken up by macrophages/Kupffer cells in the liver following their intravenous administration.
1: Miller SD et al, Nat Rev Immunol 2007.
Disclosure: This work has been supported by the Wyss Zurich, a collaboration between the ETH Zurich and the University of Zurich and was made possible by a donation from Swiss entrepreneur philanthropist Dr. hc. mult. Hansjörg Wyss.
R. Martin
Received unrestricted grants from Biogen and Novartis. Received financial compensation for lectures and advisory tasks from Biogen, Merck, Novartis, Roche, Teva, Genzyme, Neuway and CellProtect. R. Martin is a co-founder/-owner of Cellerys. R. Martin has received royalties for a NIH-held patent on the use of daclizumab in MS.
A. Lutterotti
Received financial compensation and/or travel support for lectures and advice from Biogen, Merck, Novartis, Teva, Genzyme, Bayer. A Lutterotti is a co-founder of Cellerys and Co-inventor on a patent held by the University of Zurich on the use of peptide-coupled cells for treatment of MS.
M. Hohmann, T. H. Ludersdorfer, M.J. Docampo, C. Sellés-Moreno, P.C. Englezou, J. S. Goede, J. Deuel, F. Guffanti, M.Broggini, E. Scanziani and M. Sospedra
Nothing to disclose.
Abstract: EP1592
Type: Poster Sessions
Abstract Category: Therapy - Immunomodulation/Immunosuppression
Background: The development of safer and more efficient immune therapies remains an important unmet medical need in patients with autoimmune diseases. Induction of antigen-specific immune tolerance can be achieved via injection of cells chemically coupled with target antigens. Preclinical studies with peptide-coupled splenocytes have suggested cross-tolerance“ as the main mechanism of action for inducing tolerance (1), whereby peptide-coupled cells undergo apoptosis and are processed by macrophages in the spleen to represent the antigens in a tolerogenic way. Much less is known using peptide-coupled red blood cells (RBCs) instead of peptide coupled splenocytes.
Goals: Objectives of this project are to analyze the effects of the coupling procedure on RBCs in vitro and investigate the biodistribution of peptide-coupled RBCs in vivo.
Methods and Results: Treatment with the cross-linker ethylcarbodiimide (EDC) led to a reduced deformability of peptide-coupled RBCs as observed by ektacytometry. Electron microscopy analysis revealed only minor morphological changes following treatment with EDC.
In addition, coupling of RBCs initiates physiological changes such as a rapid influx of cytosolic calcium and phosphatidylserine exposure, both hallmarks of programmed cell death in RBCs, called eryptosis.
Both deformability and morphological changes of peptide-coupled RBCs appear to influence the in vivo biodistribution and direct these cells to specific organs. To identify the cellular origin involved in the uptake of peptide-coupled RBCs, we injected fluorescently-labelled peptides coupled to RBCs intravenously in BALB/c mice and analysed the biodistribution, both in vivo and ex vivo. Bioluminiscence imaging data indicates the liver as one of the major organs involved in the uptake of peptide-coupled RBCs. Histological analysis confirmed the aforementioned findings, demonstrating uptake of peptide-coupled RBCs by liver macrophages/Kupffer cells.
Conclusion: RBCs exhibit hallmark characteristics of eryptosis following peptide coupling and these are efficiently taken up by macrophages/Kupffer cells in the liver following their intravenous administration.
1: Miller SD et al, Nat Rev Immunol 2007.
Disclosure: This work has been supported by the Wyss Zurich, a collaboration between the ETH Zurich and the University of Zurich and was made possible by a donation from Swiss entrepreneur philanthropist Dr. hc. mult. Hansjörg Wyss.
R. Martin
Received unrestricted grants from Biogen and Novartis. Received financial compensation for lectures and advisory tasks from Biogen, Merck, Novartis, Roche, Teva, Genzyme, Neuway and CellProtect. R. Martin is a co-founder/-owner of Cellerys. R. Martin has received royalties for a NIH-held patent on the use of daclizumab in MS.
A. Lutterotti
Received financial compensation and/or travel support for lectures and advice from Biogen, Merck, Novartis, Teva, Genzyme, Bayer. A Lutterotti is a co-founder of Cellerys and Co-inventor on a patent held by the University of Zurich on the use of peptide-coupled cells for treatment of MS.
M. Hohmann, T. H. Ludersdorfer, M.J. Docampo, C. Sellés-Moreno, P.C. Englezou, J. S. Goede, J. Deuel, F. Guffanti, M.Broggini, E. Scanziani and M. Sospedra
Nothing to disclose.