Search bioRxiv⌕ Search

bioRxiv · 10.1101/2025.02.13.637856

Mesenchymal Stem Cell-Derived Extracellular Vesicles Mitigate Immune Cell Activation in an In Vitro Model of Post-Resuscitation Inflammation

Abstract

BackgroundSystemic inflammation is a well-established component of post-cardiac arrest syndrome (PCAS), a condition responsible for significant morbidity and mortality in patients who are initially resuscitated from sudden cardiac arrest. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have emerged as promising immunomodulatory agents in various inflammatory conditions, including after ischemia-reperfusion injury (IRI). Here, we investigated the therapeutic potential of MSC-EVs in porcine peripheral blood mononuclear cells (PBMCs) stimulated with lipopolysaccharide (LPS) or mitochondrial DNA (mtDNA) to mimic immune cell activation in PCAS. MethodsPBMCs were isolated from healthy pigs (Sus scrofa), cultured in vitro, stimulated with LPS or mtDNA, and treated with a range of MSC-EV concentrations. Flow cytometry, quantitative PCR, ELISA, and ROS/RNS measurements were performed to assess PBMC activation. ResultsMSC-EV treatment reduced LPS-induced inflammatory granulocyte activation and selectively modulated cytokine transcripts, including IFN, IL-1{beta}, and TNF-, in a concentration-dependent manner. Similar immunosuppressive effects were observed in mtDNA-stimulated PBMCs, where MSC-EVs attenuated dendritic cell activation and inflammatory cytokine release. Furthermore, higher concentrations of MSC-EVs significantly decreased ROS/RNS production in both LPS- and mtDNA-challenged PBMCs. ConclusionsMSC-EVs exhibit potent immunomodulatory properties against LPS- and mtDNA-induced activation of porcine PBMCs, highlighting their broad capacity to modulate immune responses and mitigate oxidative stress induced by pro-inflammatory stimuli that are relevant to PCAS. These findings provide further support for the administration of MSCs, or MSC-EVs themselves, as a potential therapeutic intervention to target immune activation in PCAS and other disorders characterized by an acute systemic inflammatory state.

Source connections

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Rolland, T. J., Zahra, S., Cucinotta, D., Young, R., Weil, B. R.. 2025-02-17. Mesenchymal Stem Cell-Derived Extracellular Vesicles Mitigate Immune Cell Activation in an In Vitro Model of Post-Resuscitation Inflammation. https://doi.org/10.1101/2025.02.13.637856

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

TFAM Dependent Mitochondrial Fitness Limits CD8⁺ T Cell Immunopathology and Sustains Protective Immunity during Viral Pneumonia

During respiratory virus infection, CD8 T cells kill infected cells and establish antigen-specific memory, but mechanisms regulating these functions remain incompletely understood. Here, we identify mitochondrial transcription factor A (TFAM)-dependent mitochondrial fitness as a regulator of CD8 T cell function during influenza infection. Human CD8 T cells exhibited an age-associated decline in TFAM expression and mitochondrial function. To model this physiologically relevant decline and determine its consequences for antiviral immunity, we generated CD8 T cell-specific TFAM-haploinsufficient mice. TFAM insufficiency disrupted mitochondrial integrity and bioenergetics and increased mitochondrial DNA and oxidative stress. During influenza infection, TFAM-insufficient CD8 T cells exhibited increased cytotoxic and inflammatory activity associated with lung immunopathology without improved viral control. This early phenotype was followed by loss of effector function, diminished antigen-specific responses, reduced protection following adoptive transfer, and impaired heterosubtypic recall immunity. Thus, TFAM-dependent mitochondrial fitness is a cell-intrinsic regulator that limits immunopathology while sustaining recall immunity.

immunology↗

Gasdermin E couples mitochondrial stress to STING-driven neuronal pyroptosis during Chandipura virus encephalitis

Neurotropic RNA viruses are major causes of fatal encephalitis worldwide, yet how infected neurons transition from antiviral defense to inflammatory cell death is not well characterized. Chandipura virus (CHPV), an emerging neurotropic rhabdovirus, causes acute, rapidly progressive encephalitis with high case fatality in children, but the mechanisms underlying its neuropathogenesis remain poorly defined. Here, we demonstrate that CHPV suppresses canonical RNA virus sensing early but subsequently switches to a mitochondria-driven innate immune program that culminates in inflammatory cell death. Early infection of neuronal cells with CHPV was marked by reduced levels of the mitochondrial antiviral adaptor protein, MAVS and attenuation of type I and III interferon responses. As infection progressed, mitochondrial dysfunction promoted accumulation of mtROS, mitochondrial accumulation of cleaved GSDME and cytosolic mtDNA release, triggering STING activation, which coincided with robust neuroinflammation and pyroptotic cell death. Pharmacological inhibition or genetic silencing of STING markedly attenuated inflammatory signaling, prevented pyroptotic membrane rupture and protected neurons from cell death without significantly affecting viral replication. In contrast, GSDME depletion reduced both viral replication and neuronal death. Notably, GSDME depletion markedly attenuated STING phosphorylation, while STING depletion also reduced GSDME activation, revealing functional coupling between these pathways during CHPV-induced neuronal injury. Collectively, our findings identify a mitochondria-GSDME-STING axis linking early immune evasion to neuroinflammation during CHPV infection, revealing a previously unrecognized mechanism of inflammatory neuronal death in viral encephalitis and highlighting STING as a potential therapeutic target in certain CNS viral infections.

immunology↗

Mutanome-guided immunopeptidomics of blood plasma for neoepitope detection in solid tumors is constrained by cfDNA variant calling sensitivity and MS detection limits

Introduction: Neoepitopes form the basis of tumor-specific immune responses. Tissue biopsy, the primary source for neoepitope detection, is limited and invasive. Therefore, we aimed to identify neoepitopes by mutanome-guided immunopeptidomics from plasma of cancer patients. Methods: Mass spectrometry (MS) data analysis of HLA ligands from plasma (n = 4) was guided by patient-specific mutanomes of cell-free DNA (cfDNA) from plasma or tumor genomic DNA (tgDNA) from tissue. Matched tumor tissue and healthy donor plasma served as controls. Neoepitopes were validated with synthetic peptides, and immunogenicity was assessed using IFN-gamma ELISpot and intracellular cytokine staining. Results: Wild-type immunopeptidomes from tissue and plasma overlapped by 58%, with 91% of plasma HLA ligands rediscovered in tissue. 13 out of 15 tumor-associated HLA ligands detected in plasma were rediscovered in the matching tissue. However, no neoepitopes in plasma were identified by immunopeptidomics guided by cfDNA mutanomes, likely reflecting the limited overlap between cfDNA and tgDNA mutanomes (15%). Using the tgDNA mutanome as a complementary reference, two neoepitopes were detected in one patient's plasma, albeit at the MS detection limit. Both neoepitopes were also discovered in tissue, along with three tissue-exclusive neoepitopes. Two tissue-exclusive neoepitopes induced antigen-specific T cell responses in healthy donor PBMCs. Conclusion: In summary, plasma immunopeptidomics enables profiling of HLA ligands from wild-type proteins, including TAAs. In principle, neoepitope detection from plasma at the peptide level is feasible, but tissue remains the gold standard for variant calling and neoepitope identification. Improved detection methods may enable minimally invasive approaches in the future.

immunology↗