Biology subjects

Petrenko, O.

Publications and source records attributed to Petrenko, O..

5 recordsLinked to original sources

bioRxiv2025

Crosstalk between CD8+ T cells and systemic bile acid metabolism controls LCMV-induced immunopathology

Antiviral immunity has a profound effect on host metabolism, which can, in turn, modulate immune responses and influences disease pathology. Among its many functions, the liver orchestrates systemic bile acid (BA) metabolism, a pathway disrupted in chronic liver diseases such as viral hepatitis. BAs have become increasingly recognized for their immunomodulatory properties, and multiple BA species are being explored as therapeutic agents in liver diseases. Understanding the interplay between immune responses and BA metabolism could unlock new therapeutic opportunities based on BA modulation. Using lymphocytic choriomeningitis virus (LCMV) as a model, we investigated the interplay between chronic hepatotropic virus infection, BA metabolism and immunity. Our findings reveal that chronic LCMV infection increases BA levels and shifts circulating and liver BA composition towards host-derived, conjugated BAs. At the same time, hepatic BA transport and synthesis genes are broadly downregulated, which is at least partially dependent on CD8+ T cells. Additionally, we found that sustained high BA levels impact CD8+ T cell responses to chronic LCMV infection. Mice with elevated circulating BAs due to the lack of BA transporters OATP1a and OATP1b, showed impaired T cell expansion and reduced liver immunopathology. These findings reveal a reciprocal interplay between CD8+ T cells and BA metabolism, expanding our understanding of adaptive immunity against viral hepatitis. Moreover, it highlights how immuno-metabolic changes in liver disease may affect the bodys ability to fight infections and cancer. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=170 SRC="FIGDIR/small/670599v1_ufig1.gif" ALT="Figure 1"> View larger version (49K): org.highwire.dtl.DTLVardef@7d4bcorg.highwire.dtl.DTLVardef@1f84b5org.highwire.dtl.DTLVardef@1419686org.highwire.dtl.DTLVardef@1014b8c_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

bioRxiv2025

Spatial single-cell interactome and niche-specific molecular signatures in alcohol-related liver disease

Alcohol-related liver disease (ALD) remains a major global health burden with limited therapeutic options due to an incomplete understanding of its underlying molecular mechanisms and cellular crosstalk. Here, we applied ultra-high resolution (on 2 {micro}m spots) spatial transcriptomics to a cirrhotic liver tissue obtained from an end-stage ALD patient, analyzing >265,000 spatially resolved cells with further validation on single-cell and single-nuclei datasets from patients with ALD cirrhosis. Our analysis delineated distinct cellular sub-populations and molecular landscapes across fibrotic, vascular, and parenchymal niches of ALD cirrhosis. We identified robust zonation of hepatocytes, hepatic stellate cells, and diverse immune subpopulations, including enrichment of pro-inflammatory T cells and dendritic cells in the fibrotic niche and MARCO+ tissue-resident macrophages localizing mostly in parenchymal areas. Analysis of spatial metrics assigned expression of WNT4, RCAN3, PPIAL4G, PLA2G5, and SLC6A9 to the fibrotic environment in ALD. Differential expression and ligand-receptor interactome analyses revealed niche-specific signaling, with marked CCL19-CCR7 activity in fibrotic regions and DLL4-NOTCH3 crosstalk in vascular compartments. Notably, WNT4+ fibroblasts emerged as key mediators of extracellular matrix remodeling and chemoattraction, particularly via CCL19-mediated signaling towards CD8+ T cells, which was validated on single-cell resolution within the ALD cirrhotic liver in external datasets. These spatial and single-cell findings highlight novel potential therapeutic targets for patients with ALD cirrhosis.

systems biology↗

bioRxiv2023

STAT3 is a genetic modifier of TGF-beta induced EMT in KRAS mutant pancreatic cancer

Oncogenic mutations in KRAS are among the most common in cancer. Classical models suggest that loss of epithelial characteristics and the acquisition of mesenchymal traits are associated with cancer aggressiveness and therapy resistance. However, the mechanistic link between these phenotypes and mutant KRAS biology remains to be established. Here we identify STAT3 as a genetic modifier of TGF-beta-induced epithelial to mesenchymal transition. Gene expression profiling of pancreatic cancer cells identifies more than 200 genes commonly regulated by STAT3 and oncogenic KRAS. Functional classification of STAT3 responsive program reveals its major role in tumor maintenance and epithelial homeostasis. The signatures of STAT3-activated cell states can be projected onto human KRAS mutant tumors, suggesting that they faithfully reflect characteristics of human disease. These observations have implications for therapeutic intervention and tumor aggressiveness. SignificanceThe identification of the molecular and genetic characteristics of tumors is essential for understanding disease progression and aggressiveness. KRAS mutations are the most frequent oncogenic drivers in human cancer. In this study we demonstrate that the ubiquitously expressed transcription factor STAT3 is a genetic modifier of TGF-beta-induced EMT, and thereby oncogenic KRAS dependency. Both in vitro and in vivo studies demonstrate that STAT3 responsive program is an inherent part of oncogenic KRAS outcome.

cancer biology↗

bioRxiv2023

Transcriptomic signatures of progressive and regressive liver fibrosis and portal hypertension

Persistent liver injury triggers a fibrogenic program that causes pathologic remodelling of the hepatic microenvironment (i.e., liver fibrosis) and portal hypertension. The dynamics of gene regulation during liver disease progression and regression remain understudied. Here, we generated hepatic transcriptome profiles in two well-established liver disease models at peak fibrosis and during spontaneous regression after the removal of the inducing agents. We linked the dynamics of key liver disease readouts, such as portal pressure, collagen proportionate area, and transaminase serum levels, to most differentially expressed genes, enabling the identification of transcriptomic signatures of progressive vs. regressive liver fibrosis and portal hypertension. These candidate biomarkers (e.g., Scube1, Tcf4, Src, Hmga1, Trem2, Mafk, Mmp7) were also validated in RNA-seq datasets of patients with cirrhosis and portal hypertension. Finally, deconvolution analysis identified major cell types and suggested an association of macrophage and portal hepatocyte signatures with portal hypertension and fibrosis area in both models.

systems biology↗

bioRxiv2019

PIK3CA in KrasG12D/Trp53R172H Tumor Cells Promotes Immune Evasion by Limiting Infiltration of T Cells in a Model of Pancreatic Cancer

The presence of tumor-infiltrating T cells is associated with favorable patient outcomes, yet most pancreatic cancers are immunologically silent and resistant to currently available immunotherapies. Here we show using a syngeneic orthotopic implantation model of pancreatic cancer that Pik3ca regulates tumor immunogenicity. Genetic silencing of Pik3ca in KrasG12D/Trp53R172H-driven pancreatic tumors leads to infiltration of T cells, complete tumor regression, and 100% survival of immunocompetent host mice. By contrast, Pik3ca-null tumors implanted in T cell-deficient mice progress and kill all of the animals. Adoptive transfer of tumor antigen-experienced T cells eliminates Pik3ca-null tumors in immunodeficient mice. Loss of PIK3CA or inhibition of its effector, AKT, increases the expression of MHC Class I and CD80 on tumor cells. These changes contribute to the increased susceptibility of Pik3ca-null tumors to T cell surveillance. These results indicate that tumor cell PIK3CA-AKT signaling limits T cell recognition and clearance of pancreatic cancer cells. Strategies that target this pathway may yield an effective immunotherapy for this cancer.\n\nSIGNIFICANCEPIK3CA-AKT signaling in pancreatic cancer cells limits T cell infiltration and clearance of tumors by suppressing the surface expression of MHC Class I and CD80. Targeting the PIK3CA-AKT pathway in tumor cells provides a new avenue for discovery of novel pancreatic cancer immunotherapies.

cancer biology↗