Integrative Analyses\nof Single-Cell RNA-Sequencing\nand Bulk RNA-Sequencing Reveal Prognostic Markers of Peripheral Blood\nMononuclear Cells in Patients with Cardiogenic Shock Receiving Venous-Arterial\nExtracorporeal Membrane Oxygenation Support Co

The impact of changes in peripheral blood mononuclear\ncells (PBMCs)\non the prognosis of patients with cardiogenic shock (CS) receiving\nvenous-arterial extracorporeal membrane oxygenation (VA-ECMO) remains\nunclear. A single-cell RNA-sequencing (scRNA-seq) and a bulk RNA-sequencing\n(bulk RNA-seq) data sets of pre-ECMO PBMCs of CS patients were obtained\nfrom the gene expression omnibus database, which were analyzed using\nthe “Seurat” and “limma” packages, respectively.\nThe counts of different PMBC cell types, differential expression genes\n(DEGs), pathway enrichment analysis, cell–cell communication\nanalysis, pseudotime analysis, and immune cell infiltration analysis\nwere compared between VA-ECMO groups with different prognoses. The\nintersectional DEGs of the two data sets were screened. PBMCs were\ncollected from VA-ECMO patients for experimental verification. For\nscRNA-seq analysis, ten kinds of PBMCs were identified, and B and\nNK/NKT cells which had significant differences in cell counts across\ngroups were further divided into four subsets. The counts of B and\nNK/NKT cells with high expression levels of HSPA1B were higher in\nthe poor-prognosis group, which was consistent with the bulk RNA-seq\nanalysis. Pseudotime analysis also indicated that B-HSPA1B cells gradually\nincreased in the poor-prognosis group. HSPA1B was found to be the\nintersectional upregulated DEG in both data sets, which was consistent\nwith the experimental verification using clinical samples. The increased\ncounts of B and NK/NKT cells as well as high expression levels of\nHSPA1B in these cell types or in the total pre-ECMO PBMCs were predictors\nof poor prognosis.