Integrated transcriptomic profiling of programmed cell death patterns unveils macrophage-hepatocyte crosstalk via THBS1-CD47 axis in hepatic ischemia-reperfusion injury.

BACKGROUND

Hepatic ischemia-reperfusion injury (HIRI) is clinically linked to post-transplant complications, yet the pathogenic role of programmed cell death (PCD) patterns in this process remains poorly delineated. This study aimed to investigate the diversity of programmed cell death (PCD) patterns underlying HIRI, with a focus on mechanistically dissecting macrophage-hepatocyte crosstalk mediated by the THBS1-CD47 axis.

METHODS

GSE151648, GSE14951, GSE12720 and GSE171539 were retrieved from the Gene Expression Omnibus (GEO) database. Based on bulk transcriptomic data, we identified differentially expressed PCD-related genes (DE-PCDRGs) in HIRI samples and performed functional annotation of these genes. Furthermore, machine learning algorithms were used to select hub DE-PCDRGs closely related to HIRI, and a robust risk assessment prediction model for HIRI was constructed. Additionally, using single-cell transcriptomic data, we further elucidated 19 diverse patterns of PCD in HIRI samples at the single-cell level and validated the hub DE-PCDRGs. Crucially, we mechanistically linked the THBS1-CD47 axis to apoptosis-exacerbated liver injury via in vivo and in vitro experiments.

RESULTS

Bulk transcriptomic analysis identified 25 DE-PCDRGs consistently upregulated in HIRI samples. Machine learning algorithms further screened 5 hub DE-PCDRGs (THBS1, MAP1LC3B, PPP1R15A, CXCL8, ZC3H12A), which formed a risk prediction model that effectively classified patients into high-risk and low-risk groups. These hub genes showed elevated expression in high-risk groups, accompanied by pronounced enrichment of 5 PCD patterns (anoikis, immunogenic cell death, NETosis, Netotic cell death, pyroptosis). Single-cell analysis further uncovered 12 distinct PCD patterns within the HIRI sample microenvironment, with spatial validation confirming the 5 hub DE-PCDRGs. The HIRI animal model confirmed the occurrence of apoptosis in liver tissue and upregulation of THBS1 in macrophages. Subsequent in vitro co-culture experiments demonstrated that macrophage-derived THBS1 directly engaged hepatocyte CD47, thereby suppressing the PI3K-AKT-NF-κB signaling pathway and promoting apoptosis.

CONCLUSIONS

Our study delineated heterogeneous PCD patterns as pathological process of HIRI, demonstrating that the THBS1-CD47 axis drives macrophage-hepatocyte crosstalk to exacerbate apoptosis by inhibiting PI3K-AKT-NF-κB signaling. These results extend the current understanding of HIRI pathogenesis and nominate THBS1-CD47 as a promising candidate target.