Ex vivo pretreatment of human vessels with siRNA nanoparticles provides protein silencing in endothelial cells

Abstract

Human endothelial cells are initiators and targets of the rejection response. Pre-operative modification of endothelial cells by small interfering RNA transfection could shape the nature of the host response post-transplantation. Ablation of endothelial cell class II major histocompatibility complex molecules by small interfering RNA targeting of class II transactivator can reduce the capacity of human endothelial cells to recruit and activate alloreactive T cells. Here, we report the development of small interfering RNA-releasing poly(amine-co-ester) nanoparticles, distinguished by their high content of a hydrophobic lactone. We show that a single transfection of small interfering RNA targeting class II transactivator attenuates major histocompatibility complex class II expression on endothelial cells for at least 4 to 6 weeks after transplantation into immunodeficient mouse hosts. Furthermore, silencing of major histocompatibility complex class II reduces allogeneic T-cell responses in vitro and in vivo. These data suggest that poly(amine-co-ester) nanoparticles, potentially administered during ex vivo normothermic machine perfusion of human organs, could be used to modify endothelial cells with a sustained effect after transplantation.

Organ preservation with targeted rapamycin nanoparticles: a pre-treatment strategy preventing chronic rejection in vivo

“…In addition, these studies also established that rapamycin significantly reduces the secretion of IL-6 3. The ability of nano-based targeting of small interfering RNA (siRNA) to disrupt EC MHC expression and thereby reduce recruitment and activation in T cells in the setting of transplantation has also been successfully explored and bolsters the idea that pre-treatment in this setting may prevent long term dysfunction 2. Taken together, these data support the use of rapamycin encapsulated as a targeted nanotherapeutic micelle to abrogate transplant fibrosis and vasculopathy when used as a donor organ preservation pre-treatment strategy.…”

Emerging technologies in organ preservation, tissue engineering and regenerative medicine: a blessing or curse for transplantation?

“…Not only is machine perfusion beneficial to allograft preservation, storage and transportation, this technology also offers the perfect platform for ex vivo treatment of organs in order to minimize injury or even facilitate regeneration and tissue repair . This is especially beneficial in the context of ECD and DCD donation, as these grafts are most susceptible to ischemic injury and would profit the most from reparative attempts.…”

“…The potential of small interfering RNA (siRNA) has further been shown by Cui et al . . The group was able to mitigate major histocompatibility complex class II expression on endothelial cells using siRNA targeting class II transactivator in human vessels and murine systems.…”

The future of marginal kidney repair in the context of normothermic machine perfusion

“…One of the primary benefits of NPs is their modularity. The polymer type can be varied to enable encapsulation of various classes of therapeutics from small molecules to nucleic acid–based drugs 35, 36. In addition, NPs can be formulated to provide sustained therapeutic release with the rate of release controlled by polymer molecular weight.…”

“…Polymeric nanoparticles (NPs) have a long history of safe use in humans as drug delivery vehicles for the treatment of a wide variety of diseases. [33][34][35] One of the primary benefits of NPs is their modularity.…”