Postdoctoral Fellow Centre for Translational Stem Cell Biology, Hong Kong
Abstract: African Swine Fever (ASF) is highly contagious and lethal disease in domestic pigs. Pulmonary alveolar macrophages (PAMs), which have long been adopted for host-pathogen interaction studies, are known typical host cells for virus infection and propagation, particularly for African Swine Fever virus (ASFV). However, limited lifespan and batch-to-batch variation of PAMs hinder experimental reproducibility and scalability, highlighting alternative models are needed. In this study, we utilized porcine expanded potential stem cells (pEPSCs) to establish a renewable in vitro supply of functional and experimentally tractable monocyte-macrophages that share similar phenotypes and features with ex vivo PAMs. This culture system is a serum- and feeder-free system involving the generation of embryoid bodies (EBs) from porcine EPSCs, followed by the formation of mesoderm and hematopoietic specification. Transcriptional profile revealed mesoderm fate transition for porcine EPSC differentiation under bone morphogenetic protein (BMP), WNT, transforming growth factor-beta (TGF-β), and VEGF signalling, enabling the acquisition of hemogenic-like signatures. The derived hemogenic intermediate allowed for the directed differentiation of hematopoietic progenitor cells (HPCs), which can be further differentiated into the myeloid lineage. The efficient and robust gene editing capacity of porcine EPSCs offers new opportunities to investigate the functional genetics and molecular dynamics of host-pathogen interactions. Overall, our newly identified culture system supports the derivation of cells closely resembling ex vivo porcine primary macrophages, providing a valuable and renewable cell source for viral studies and informing potential therapeutic strategies against porcine viruses.
Funding Source: This project is supported by Health@InnoHK, Innovation Technology Commission, HKSAR
