Fig. 6
Integrative analyses of a large-cohort COVID-19 single-cell transcriptomic dataset with our single-cell datasets reveal that NK2.1 cells from elderly COVID-19 patients are enriched for type I interferon signalling which correlates with increased disease severity in COVID-19. A Flowchart showing the integrative analysis of the scRNA-seq datasets of peripheral blood NK cells obtained from healthy controls (HC, n = 18) and COVID-19 patients (n = 56) [23, 25, 56]. B, C UMAP projections of the integrated single-cell transcriptomes of 34,388 NK cells, with 17,748 cells from healthy control individuals and 16,640 cells from COVID-19 patients. Cells are coloured by subset identity (B), and the NK cell subsets were defined as in Fig. 2B (C). Each dot represents a single cell. D Bar graph showing the proportion of each NK cell subset in all cells. E Bar graph showing the proportion of cells derived from young or elderly samples for each of the NK cell subsets. F Histograms showing the number of DEGs for each NK cell subset in the total individuals (top), the elderly individuals (middle), and the young individuals (bottom) between COVID-19 patients and healthy controls. G Dot plots of enriched GO terms of differentially expressed genes among NK2.1 cells between elderly COVID-19 patients and elderly healthy control individuals. The colour of the dot indicates -log10 (P-value) enrichment for each GO term, and the size of the dot indicates the number of differentially expressed genes contained within each enriched GO term. H Box plots of the average expression of genes involved in the signalling pathway “response to type I interferon” in NK2.1 cells from young healthy control individuals, from elderly healthy control individuals, from young COVID-19 patients, and from elderly COVID-19 patients