Fig 2: MUG1 downregulated neutrophil degranulation and pro-inflammatory cytokine release. (A) Experimental design. (B) Neutrophils treated with IL-1ß induced MMP-9 release, a surrogate marker of neutrophil degranulation. IL-1ß stimulated release of MMP-9 was attenuated by supplementation of MUG1. (C) Heatmap ranking of the 13 IL-1ß stimulated neutrophil proteins decreased by MUG1. (D) By enrichment analysis, IL-17 signaling was the most enriched pathway for the MUG1 downregulated proteins (top). By volcano plotting, MMP-9, MPO, and NGAL were the IL-1ß induced neutrophil proteins most downregulated by MUG1 (bottom). Sample sizes were n = 8, 4M/4F per paired group; analysis done by one way ANOVA with Student Newman–Keuls post-hoc test, paired Students t-test, and Enrichr pathway analysis.

Fig 3: MI D1 Macrophage secretome analysis revealed MUG1 as the highest upregulated protein and USP48 as the highest downregulated protein. (A) Heat map ranking of proteins by p value and fold-change at MI D1 vs. D0. (B) By Volcano plot, MUG1 was the most upregulated and USP-48 the most downregulated protein. (C) PLS-DA 2D scores plot shows a significant shift in proteome of D0 vs. D1 macrophage secretome. (D) Enrichment analysis shows that for MI D1 upregulated proteins (top), IL-17 signaling was the most enriched pathway. Of the downregulated proteins (bottom), PPAR signaling was the most enriched pathway. Sample sizes were n = 4 pooled M sets; analysis by unpaired Students t-test and Enrichr pathway analysis.

Fig 4: Macrophage coordination of neutrophil physiology. Macrophages inhibit neutrophil degranulation by secretion of MUG1 and induce neutrophil degranulation by secretion of Lgals3 to coordinate LV wall thinning and early MI wound healing. Release of MMP-9 provides an additional feedback to proteolyze and activate Lgals3.

Fig 5: D1 MI macrophage secretome reduced neutrophil degranulation through MUG1. (A) Experimental design. (B) Neutrophils treated with phorbol 12-myristate-13-acetate (PMA) induced MMP-9 release, a surrogate marker of degranulation. Treatment with MI D1 macrophage secretome (10%, by volume) significantly reduced MMP-9 release, an effect reversed by addition of a MUG1 blocking antibody. (C) Heatmap of the top 25 proteins ranked by p value for the comparison of PMA + MI D1 macrophage secretome + MUG1 Ab vs. PMA + MI D1 macrophage secretome. (D) For the proteins downregulated by the D1 MI macrophage secretome, cytokine-cytokine receptor interaction signaling was most enriched (top). For the proteins upregulated by addition of a MUG1 blocking Ab to PMA+ MI D1 macrophage secretome, cytokine-cytokine receptor interaction was most enriched (bottom). Sample sizes were n = 4M per paired group; analysis by one way ANOVA with Student Newman–Keuls post-hoc test, paired Students t-test, and Enrichr pathway analysis.