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Cell and Tissue Transplantation: Allo & Xeno

Saturday September 25, 2021 - 15:50 to 17:05

Room: General Session

310.1 Evaluating the immunomodulatory properties of human placenta amniotic epithelial cells as a therapeutic in ex vivo lung reconditioning

Chelsea Griffiths, United Kingdom

PhD Student/Research Assistant
Clinical and translational research institute
Newcastle University


Evaluating the immunomodulatory properties of human placenta amniotic epithelial cells as a therapeutic in ex vivo lung reconditioning

Chelsea Griffiths1,2, Lu Wang1,2, Lucy Bates1,2,3, Chong Yun Pang1, Marnie Brown1,2, John Dark1,2, Simi Ali1,2, Andrew Fisher1,2,3, William Scott III1,2.

1Translational and Clinical Research Institute, Newcastle University, Newcastle Upon Tyne, United Kingdom; 2NIHR Blood and Transplant Research Unit in Organ Donation and Transplantation, Newcastle upon Tyne, United Kingdom; 3Institute of Transplantation, Freeman Hospital, Newcastle upon Tyne, United Kingdom

Introduction: Ex Vivo Lung Perfusion (EVLP) provides a platform for the evaluation and reconditioning of donor lungs deemed unsuitable for transplant. EVLP offers a normothermic isolated environment which provides a unique opportunity to administer advanced therapeutics, including cell-based therapies such as human Amniotic Epithelial Cells (hAECs). hAECs have been demonstrated to have immunomodulatory properties that could minimize Ischemia Reperfusion Injury (IRI) and potentially recondition extended criteria donor lungs. We investigated hAECs administered during EVLP using lungs turned down for transplant.

Methods: hAECs were isolated from term placenta through enzymatic digestion then assessed for purity through flow cytometry. Phagocytosis of pHrodo BioParticles™ by THP-1 derived macrophages treated with hAECs for 6 hours was determined through flow cytometry (n=5). Neutrophils isolated from whole blood were migrated through an IL-1β activated human dermal microvascular endothelial cell (HMEC-1) monolayer with and without treatment of hAECs for 6 hours (n=3). Human lungs turned down for transplant were seperated into two single lungs, with 150 x 106 hAECs or the HTR cell line administered to each lung respectively then perfused concurrently for 4-6 hours (n=2). Serial samples of perfusate and tissue biopsies were collected for enzyme-linked immunosorbent assay (ELISA) and immunofluorescence (IF) staining respectively. 

Results: hAECs can be successfully isolated, yielding approximately 150 x 10cells from each placenta, with >95% purity and  >90% viability. An in vitro transendothelial migration model demonstrated hAECs can reduce neutrophil chemotaxis through IL-1β activated HMEC-1 cells. The hAEC-treated macrophages demonstrated an enhanced phagocytic ability in vitro. hAEC-treated lungs exhibited improved gaseous exchange, a reduction in CXCL8 and TNFα, and increased IL-10 expression in the perfusates compared to the HTR cell-treated lungs. IF staining of the biopsies exhibited reduced expression of CXCL8 and oxidative stress marker 3-nitrotyrosine in hAEC-treated lungs.

Conclusion: In vitro assays demonstrated the potential of hAECs to minimise neutrophil chemotaxis and increase macrophage phagocytosis, which are key players in IRI. hAEC-treated lungs led to a downregulation of key pro-inflammatory markers, an upregulation of anti-inflammatory marker expression and the lungs showed improved gas exchange.

NIHR Blood and Transplant Research Unit .