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

• Published in: Cytotherapy (Oxford, England) Vol. 21; no. 5; pp. S49 - S50
• Main Authors: Griffiths, C, Charlton, C, Scott, W, Ali, S, Fisher, A.J
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.05.2019
• Subjects: Advanced Basic Science; Other
• ISSN: 1465-3249; 1477-2566
• DOI: 10.1016/j.jcyt.2019.03.405

Background & AimEx Vivo Lung Perfusion (EVLP) provides a platform for the evaluation and reconditioning of donor lungs deemed unsuitable for transplant. Elevated expression of pro-inflammatory cytokines leading to activation of pulmonary endothelium is associated with poor outcomes after lung transplantation. EVLP offers a platform to administer advanced therapeutics, including cell-based therapies such as human Amniotic Epithelial Cells (hAECs). This study aims to evaluate the immunomodulatory properties of hAECs against macrophage and endothelial activation. Methods, Results & ConclusionhAECs were isolated from term-placenta through enzymatic digest and cultured for 4 days to generate conditioned media. Isolated cells were characterised using immunocytochemistry and flow cytometry for surface markers. The THP-1 monocytic cell line was differentiated into macrophages using phorbol 12-myristate 13-acetate (PMA) then treated with IFNγ and LPS to generate pro-inflammatory macrophages. ELISA and qPCR were used to detect any decrease in IL-8 and TNFα expression upon subsequent treatment with hAEC conditioned media. hAECs were co-cultured alongside IL-1β activated Human Pulmonary Microvascular Endothelial Cells (HPMEC), activation markers ICAM-1 and VCAM were assessed through flow cytometry.Three term-placenta were used to harvest hAECs through a serum-free process, generating large yields of viable cells. Isolated hAECs strongly expressed epithelial cell marker EpCAM (>90%) but not markers of endothelial or mesenchymal cells (≤ 2%). A significant decrease was observed for IL-8 (p=0.0001) and TNFα (p=0.004, p=0.0001) protein expression upon hAEC treatment of pro-inflammatory macrophages at 6 and 24 hours compared to the LPS control. Conditioned media treatment also leads to a 1.2-fold decrease in IL-8 gene expression compared to the LPS control at 6 hours. Mean fluorescence intensity decreased by 1.3 and 1.4-fold for ICAM-1 and VCAM respectively on hAEC treated HPMEC compared to the IL-1β control, with percentage cell expression being lowered. Correspondingly, IL-8 protein expression was significantly decreased.In this study, we demonstrated the potential for hAECs to reduce the production of key inflammatory cytokines (IL-8 and TNFα) from pro-inflammatory macrophages and activated pulmonary endothelium, alongside lowering expression of key endothelium activation markers. Future studies plan to assess the therapeutic potential of hAECs within the EVLP platform.