Fig. 3: Differential immune response in children and adults.
a, Heat maps depicting cell–cell communications between all identified cell types derived from linear-scaled ligand–receptor interaction counts in children (left, n = 18 SARS-CoV-2 negative, n = 11 SARS-CoV-2 positive early infection phase (dps ≤ 4), n = 11 SARS-CoV-2 positive late infection phase (dps 5–12)) and adults (right, n = 23 SARS-CoV-2 negative, n = 13 SARS-CoV-2 positive early infection phase, n = 8 SARS-CoV-2 positive late infection phase). b, Dot plots depicting expression of genes involved in antiviral and cytotoxic response of myeloid dendritic cells and different macrophage populations. Each significant increase comparing SARS-CoV-2-negative children (n = 18) with SARS-CoV-2-negative adults (n = 23) and SARS-CoV-2-positive children during the early (n = 11) or late (n = 11) infection phase with SARS-CoV-2-positive adults amid early (n = 13), or late (n = 8) infection phase, respectively, is marked by a red circle (Benjamini–Hochberg-adjusted two-tailed Wilcoxon, P < 0.05). Ave. exp., average gene expression; Pct. exp., percentage of cells expressing the gene. c, UMAP displaying the different T/NK cell subpopulations in the nose of children and adults. In comparison, scaled density plots are shown indicating the proportion of the different T/NK cells in children and adults separated by their SARS-CoV-2 infection status. Yellow represents high density; blue represents low density. d, Violin plots showing expression of representative immune mediators of the CTL2 subpopulation comparing SARS-CoV-2-negative children (n = 18) with SARS-CoV-2-negative adults (n = 23) and SARS-CoV-2-positive children during the early (n = 11) or late (n = 11) infection phase with SARS-CoV-2-positive adults amid the early (n = 13) or late (n = 8) infection phase, respectively. Each dot represents one cell. Plots show median, ***P < 0.001 (IFNG negative: 1.50 × 10−17, IFNG early phase: 1.14 × 10−47, IFNG late phase: 1.69 × 10−27, CCL5 negative: 5.97 × 10−30, CCL5 late phase: 6.32 × 10−73), derived from two-tailed Wilcoxon comparison.
