Identification of the biological processes, immune cell landscape, and hub genes shared by acute anaphylaxis and ST-segment elevation myocardial infarction

Abstract

Background: Patients with anaphylaxis are at risk for ST-segment elevation myocardial infarction (STEMI). However, the pathological links between anaphylaxis and STEMI remain unclear. Here, we aimed to explore shared biological processes, immune effector cells, and hub genes of anaphylaxis and STEMI. Methods: Gene expression data for anaphylactic (GSE69063) and STEMI (GSE60993) patients with corresponding healthy controls were pooled from the Gene Expression Omnibus database. Differential expression analysis, enrichment analysis, and CIBERSORT were used to reveal transcriptomic signatures and immune infiltration profiles of anaphylaxis and STEMI, respectively. Based on common differentially expressed genes (DEGs), Gene Ontology analysis, cytoHubba algorithms, and correlation analyses were performed to identify biological processes, hub genes, and hub gene-related immune cells shared by anaphylaxis and STEMI. The robustness of hub genes was assessed in external anaphylactic (GSE47655) and STEMI (GSE61144) datasets. Furthermore, a murine model of anaphylaxis complicated STEMI was established to verify hub gene expressions. The logistic regression analysis was used to evaluate the diagnostic efficiency of hub genes. Results: 265 anaphylaxis-related DEGs were identified, which were associated with immune-inflammatory responses. 237 STEMI-related DEGs were screened, which were involved in innate immune response and myeloid leukocyte activation. M0 macrophages and dendritic cells were markedly higher in both anaphylactic and STEMI samples compared with healthy controls, while CD4⁺ naïve T cells and CD8⁺ T cells were significantly lower. Enrichment analysis of 33 common DEGs illustrated shared biological processes of anaphylaxis and STEMI, including cytokine-mediated signaling pathway, response to reactive oxygen species, and positive regulation of defense response. Six hub genes were identified, and their expression levels were positively correlated with M0 macrophage abundance and negatively correlated with CD4⁺ naïve T cell abundance. In external anaphylactic and STEMI samples, five hub genes (IL1R2, FOS, MMP9, DUSP1, CLEC4D) were confirmed to be markedly upregulated. Moreover, experimentally induced anaphylactic mice developed impaired heart function featuring STEMI and significantly increased expression of the five hub genes. DUSP1 and CLEC4D were screened as blood diagnostic biomarkers of anaphylaxis and STEMI based on the logistic regression analysis. Conclusion: Anaphylaxis and STEMI share the biological processes of inflammation and defense responses. Macrophages, dendritic cells, CD8⁺ T cells, and CD4⁺ naïve T cells constitute an immune cell population that acts in both anaphylaxis and STEMI. Hub genes (DUSP1 and CLEC4D) identified here provide candidate genes for diagnosis, prognosis, and therapeutic targeting of STEMI in anaphylactic patients.

Keywords: STEMI; anaphylaxis; hub gene; immune response; inflammation.

FIGURE 1

Transcriptomic signature of acute anaphylaxis. (A), Volcano plot of transcripts from GSE69063 (anaphylaxis dataset), where blue indicates downregulated DEGs, red represents upregulated DEGs, and gray indicates genes without significant differences. (B), Heatmap of DEGs from GSE69063. Blue indicates downregulated DEGs and red represents upregulated DEGs. (C) GO analysis of DEGs from GSE69063. The color indicates the -log10(qvalue) of the biological process (BP) terms, and the count represents the number of genes enriched in a BP term. (D), KEGG analysis of DEGs.

FIGURE 2

Immune cell characterization of acute anaphylaxis. (A), Histogram of the distribution of 22 immune cell subtypes in GSE69063 (anaphylaxis dataset). (B), Boxplot of the fraction of 22 immune cell subtypes in control and anaphylactic specimens.

FIGURE 3

Transcriptomic signature of STEMI. (A), Volcano plot of transcripts from GSE60993 (STEMI dataset), where green indicates downregulated DEGs, orange represents upregulated DEGs, and gray indicates genes without significant differences. (B), Heatmap of DEGs from GSE60993. Green indicates downregulated DEGs and orange represents upregulated DEGs. (C) GO enrichment analysis of DEGs from GSE60993. The color indicates -log10(qvalue) of the BP terms, and the count represents the number of genes enriched in a BP term. (D), KEGG analysis of DEGs from GSE60993.

FIGURE 4

Immune cell characterization of STEMI. (A), Histogram of the composition and distribution of 22 immune cell subtypes in GSE60993 (STEMI dataset). (B), Boxplot of the fraction of 22 immune cell subtypes in control and STEMI specimens.

FIGURE 5

Key transcripts shared by anaphylaxis and STEMI. (A), Venn diagram of anaphylaxis-related DEGs and STEMI-related DEGs. (B), The PPI network of 33 common DEGs. (C), GO analysis of 33 common DEGs from three perspectives: biological process (BP), cellular component (CC), and molecular function (MF). (D), The Venn diagram showing six hub genes at the intersection of six algorithms (DMNC, Stress, MCC, Degree, Closeness, Radiality). (E), Interactions of six hub genes exhibited by cytoHubba. (F), Co-expression and co-localization network of hub genes constructed by GeneMANIA.

FIGURE 6

Pearson’s correlation analysis between hub genes and immune effector cells. (A), Venn diagram of anaphylaxis-related cell subsets and STEMI-related cell subsets. (B), Scatter diagrams of the correlations between hub gene expression and M0 macrophage abundance in anaphylactic samples (blue) and STEMI samples (black). (C), Scatter diagrams of the correlations between hub gene expression and CD4⁺ naïve T cell abundance in anaphylactic samples (blue) and STEMI samples (black). R > 0 indicates positively correlated and R < 0 indicates negatively correlated. p < 0.05 was considered statistically significant.

FIGURE 7

Validation of hub gene expression in GSE47655 (anaphylaxis) and GSE61144 (STEMI) datasets. (A), Validation of hub gene expression (IL1R2, S100A12, FOS, MMP9, DUSP1, CLEC4D) in GSE47655 (anaphylaxis dataset). (B), Validation of hub gene expression (IL1R2, S100A12, FOS, MMP9, DUSP1, CLEC4D) in GSE61144 (STEMI dataset).

FIGURE 8

Verification of hub gene expression in a murine model of anaphylaxis complicated with STEMI. (A), Schematic diagram of the experimental protocol for establishing the murine model. 6-week-old female mice were subcutaneously sensitized on day 0 with 50 μg BSA in CFA and boosted subcutaneously on day 7 and day 14 with 50 μg BSA in IFA. On day 21, mice were intravenously injected with 15 μg BSA to induce systemic anaphylaxis. After the BSA challenge, the anaphylactic mice showed acute and transient ST-segment elevations on electrocardiograms. (B), Severity of anaphylactic response was scored on a scale of 0–4 (n = 6 per group). Score 0: normal; score 1: slow motions; score 2: impaired mobility, still reacting to touch; score 3: immobilized and does not react to touch; score 4: death. (C), Representative electrocardiograms of naïve mice and model mice. (D) through (F), Heart function was measured with echocardiography 10 min after BSA challenge. Representative echocardiogram (D), ejection fraction (EF%) (E), and fractional shortening (FS%) (F) of naïve mice and model mice (n = 6 per group). (G) through (K), qRT-PCR analysis of IL1R2 (G), FOS (H), MMP9 (I), DUSP1 (J), and CLEC4D (K) in peripheral whole blood (n = 6 per group). (L) through (Q), qRT-PCR analysis of FOS (L), STAT3 (M), STAT6 (N), SP1 (O), SRF (P), and CREM (Q) in peripheral whole blood (n = 8 per group). Naïve indicates untreated control mice. IC indicates BSA-treated model mice. *p < 0.05, **p < 0.01, ***p < 0.001. Statistical analysis: unpaired Student’s t-test (E, F, K, P), Kolmogorov-Smirnov test (G, I, J, N, O), Unpaired t-test with Welch’s correction (H), Mann Whitney test (L).

FIGURE 9

Identification of diagnostic efficiency of hub genes based on logistic regression models. (A), Receiver operating characteristic (ROC) curves of five hub genes in the anaphylactic dataset (GSE69063). (B), ROC curves of DUSP1+CLEC4D in the anaphylactic dataset (GSE69063). (C), Validation of the diagnostic efficiency of DUSP1+CLEC4D in the independent anaphylactic dataset (GSE47655). (D), ROC curves of five hub genes in the STEMI datasets (GSE60993 and GSE61144). (E), Validation of the diagnostic efficiency of DUSP1+CLEC4D in the STEMI datasets (GSE60993 and GSE61144).