Transcriptional effects of SARS-CoV-2 and their VLPs (virus-like particles) on human GM-CSF-derived macrophages

Analysis of the transcriptional signature of VLPs and SARS-CoV-2-infected human GM-CSF-dependent monocyte-derived macrophages. Methods: Human Peripheral Blood Mononuclear Cells (PBMC) were isolated from buffy coats from donors over a Lymphoprep gradient according to standard procedures. Monocytes were purified from PBMC by magnetic cell sorting using anti-CD14 microbeads (>95% CD14+ cells). Monocytes from three independent donors (0.5 x 106 cells/ml, >95% CD14+ cells) were cultured in RPMI 1640 supplemented with 10% fetal bovine serum (FBS) at 37°C in a humidified atmosphere with 5% CO2 and 21% O2 for 7 days in the presence of 1000 U/ml GM-CSF, with cytokine addition every two days. Then, monocyte-derived macrophages were exposed SARS-CoV-2 (SARS-CoV-2 clinical isolate Gisaid EPI_ISL_1120962, corresponding to ancestral S D614G, at an MOI=1), SARS-CoV-2-derived VLPs (MOCK) or nothing (UNT). After 4,12 and 36 hours, cells were lysed and RNA isolated for transcriptional analysis. We performed gene expression profiling analysis using data obtained from RNA-seq of 4 different donors. Comparative gene expression profiling analysis of RNA-seq data for GM-CSF-derived macrophages infected with SARS-CoV-2 or SARS-CoV-2-derived VLPs