GENE THERAPY DURING EX-VIVO LUNG PERFUSION FOR TREATMENT OF PRIMARY GRAFT DYSFUNCTION AFTER LUNG TRANSPLANTATION

Lung transplantation (LTx) is the ultimate therapy for patients with
end-stage lung disease. However, survival is poor (56% at 5 years)
compared to other solid organ transplants. Primary Graft Dysfunction
(PGD) is an important risk factor for poor survival. Severe PGD
occurs in 30% of patients after LTx and presents as lung edema,
impaired gas exchange and decreased compliance. Treatment
options for PGD however are limited. Normothermic ex-vivo lung
perfusion (EVLP) maintains the isolated lung grafts in a physiologic
and metabolic state before implantation and offers a unique platform
for treatment. With gene therapy (CRISPR) we aim to silence PGDrelated
genes during EVLP. Therefore, we will administer an adenoassociated
viral (AAV) vector that can safely introduce CRISPR-Cas9
in the cells of the lung. Firstly, we will validate a model of rat PGD
after sequential EVLP and LTx where we can quantify PGD by invivo
CT imaging and pulmonary function (compliance, gas
exchange). Secondly, we aim to observe transgene expression
during rat EVLP and after LTx with the use of a luciferase encoding
AAV vector. Thirdly, we aim to investigate if a CRISPR-Cas9
encoding AAV vector – targeted against a PGD-gene of interest (e.g.
IL-6) – can reduce the severity of PGD after rat EVLP and LTx.
Combining CRISPR-Cas9 gene silencing and AAV vector delivery
during EVLP is an innovative concept that enables us to explore new
strategies for PGD and lung treatment in general.