Proteome Profiling of PMJ2-R and Primary Peritoneal Macrophages

Genotype-driven sensitivity of mice to tick-borne encephalitis virus correlates with differential host responses in peripheral macrophages and brain

BACKGROUND

Tick-borne encephalitis (TBE) is the most common tick-borne viral infection in Eurasia. Outcomes range from asymptomatic infection to fatal encephalitis, with host genetics likely playing a role. BALB/c mice have intermediate susceptibility to TBE virus (TBEV) and STS mice are highly resistant, whereas the recombinant congenic strain CcS-11, which carries 12.5% of the STS genome on the BALB/c background, is more susceptible than BALB/c mice. In the present study, we employed these genetically distinct mouse models to investigate the host response to TBEV infection in both peripheral macrophages, one of the initial target cell populations, and the brain, the terminal target organ of the virus.

METHODS

TBEV growth and the production of key cytokines and chemokines were measured and compared in macrophages derived from BALB/c, CcS-11, and STS mice. In addition, brains from these TBEV-infected mouse strains underwent in-depth transcriptomic analysis.

RESULTS

Virus production in BALB/c and CcS-11 macrophages exhibited similar kinetics 24 and 48 h post-infection (hpi), but CcS-11 macrophages yielded significantly higher titers 72 hpi. Macrophages from both sensitive strains demonstrated elevated chemokine and proinflammatory cytokine production upon infection, whereas the resistant strain, STS, showed no cytokine/chemokine activation. Transcriptomic analysis of brain tissue demonstrated that the genetic background of the mouse strains dictated their transcriptional response to infection. The resistant strain exhibited a more robust cell-mediated immune response, whereas both sensitive strains showed a less effective cell-mediated response but increased cytokine signaling and signs of demyelination, with loss of oligodendrocytes.

CONCLUSIONS

Our findings suggest that variations in susceptibility linked to host genetic background correspond with distinct host responses, both in the periphery upon virus entry into the organism and in the brain, the target organ of the virus. These results provide insights into the influence of host genetics on the clinical trajectory of TBE.

Preconditioning of Mesenchymal Stem Cells Enhances the Neuroprotective Effects of Their Conditioned Medium in an Alzheimer's Disease In Vitro Model

BACKGROUND

Alzheimer's disease (AD) develops as a result of oxidative damage to neurons and chronic inflammation of microglia. These processes can be influenced by the use of a conditioned medium (CM) derived from mesenchymal stem cells (MSCs). The CM contains a wide range of factors that have neurotrophic, antioxidant, and anti-inflammatory effects. In addition, the therapeutic potential of the CM can be further enhanced by pretreating the MSCs to increase their paracrine activity. The current study aimed to investigate the neuroprotective effects of CM derived from MSCs, which were either activated by a TLR3 ligand or exposed to CoCl2, a hypoxia mimetic (pCM or hCM, respectively), in an in vitro model of AD.

METHODS

We have developed a novel in vitro model of AD that allows us to investigate the neuroprotective and anti-inflammatory effects of MSCs on induced neurodegeneration in the PC12 cell line and the activation of microglia using THP-1 cells.

RESULTS

This study demonstrates for the first time that pCM and hCM exhibit more pronounced immunosuppressive effects on proinflammatory M1 macrophages compared to CM derived from untreated MSCs (cCM). This may help prevent the development of neuroinflammation by balancing the M1 and M2 microglial phenotypes via the decreased secretion of proinflammatory cytokines (IL-1β, IL-6, and TNF-α) and increased secretion of IL-4, as well as the expression of IL-10 and TGF-β by macrophages. Moreover, a previously unknown increase in the neurotrophic properties of hCM was discovered, which led to an increase in the viability of neuron-like PC12 cells under H2O2-induced oxidative-stress conditions. These results are likely associated with an increase in the production of growth factors, including vascular endothelial growth factor (VEGF). In addition, the neuroprotective effects of CM from preconditioned MSCs are also mediated by the activation of the Nrf2/ARE pathway in PC12 cells.

CONCLUSIONS

TLR3 activation in MSCs leads to more potent immunosuppressive effects of the CM against pro-inflammatory M1 macrophages, while the use of hCM led to increased neurotrophic effects after H2O2-induced damage to neuronal cells. These results are of interest for the potential treatment of AD with CM from preactivated MSCs.

Endothelial deubiquinatase YOD1 mediates Ang II-induced vascular endothelial-mesenchymal transition and remodeling by regulating β-catenin

Hypertension is a prominent contributor to vascular injury. Deubiquinatase has been implicated in the regulation of hypertension-induced vascular injury. In the present study we investigated the specific role of deubiquinatase YOD1 in hypertension-induced vascular injury. Vascular endothelial endothelial-mesenchymal transition (EndMT) was induced in male WT and YOD1-/- mice by administration of Ang II (1 μg/kg per minute) via osmotic pump for four weeks. We showed a significantly increased expression of YOD1 in mouse vascular endothelial cells upon Ang II stimulation. Knockout of YOD1 resulted in a notable reduction in EndMT in vascular endothelial cells of Ang II-treated mouse; a similar result was observed in Ang II-treated human umbilical vein endothelial cells (HUVECs). We then conducted LC-MS/MS and co-immunoprecipitation (Co-IP) analyses to verify the binding between YOD1 and EndMT-related proteins, and found that YOD1 directly bound to β-catenin in HUVECs via its ovarian tumor-associated protease (OTU) domain, and histidine at 262 performing deubiquitination to maintain β-catenin protein stability by removing the K48 ubiquitin chain from β-catenin and preventing its proteasome degradation, thereby promoting EndMT of vascular endothelial cells. Oral administration of β-catenin inhibitor MSAB (20 mg/kg, every other day for four weeks) eliminated the protective effect of YOD1 deletion on vascular endothelial injury. In conclusion, we demonstrate a new YOD1-β-catenin axis in regulating Ang II-induced vascular endothelial injury and reveal YOD1 as a deubiquitinating enzyme for β-catenin, suggesting that targeting YOD1 holds promise as a potential therapeutic strategy for treating β-catenin-mediated vascular diseases.

Mesenchymal Stem Cells Attenuates Hirschsprung diseases - Associated Enterocolitis by Reducing M1 Macrophages Infiltration via COX-2 Dependent Mechanism

OBJECTIVE AND DESIGN

Hirschsprung disease-associated enterocolitis (HAEC) is a common life-threatening complication of Hirschsprung disease (HSCR). We aimed to investigate the effectiveness, long-term safety and the underlying mechanisms of Mesenchymal stem cells (MSCs) based therapy for HAEC.

MATERIAL OR SUBJECTS

Specimens from HSCR and HAEC patients were used to assess the inflammatory condition. Ednrb knock-out mice was used as HAEC model. MSCs was intraperitoneally transplanted into HAEC mice. The therapy effects, long-term outcome, safety and toxicity and the mechanism of MSCs on the treatment of HAEC were explored in vivo and in vitro.

RESULTS

Intestinal M1 macrophages infiltration and severe inflammation condition were observed in HAEC. After the injection of MSCs, HAEC mice showed significant amelioration of the inflammatory injury and inhibition of M1 macrophages infiltration. The expression levels of pro-inflammatory cytokines (TNF-α and IFN-γ) were decreased and anti-inflammatory cytokines (IL-10 and TGF-β) were increased. In addition, we found that effective MSCs homing to the inflamed colon tissue occurred without long-term toxicity response. However, COX-2 inhibitor could diminish the therapeutic effects of MSCs. Using MSCs and macrophages co-culture system, we identified that MSCs could alleviate HAEC by inhibiting M1 macrophages activation through COX-2-dependent MAPK/ERK signaling pathway.

CONCLUSIONS

MSCs ameliorate HAEC by reducing M1 macrophages polarization via COX-2 mediated MAPK/ERK signaling pathway, thus providing novel insights and potentially promising strategy for the treatment or prevention of HAEC.

Pickering emulsions as an effective route for the preparation of bioactive composites: A study of nanocellulose/polyaniline particles with immunomodulatory effect

Several studies have reported on application of cellulose particles for stabilizing Pickering emulsions (PE). Here we employ an original approach that involves using these particles as a part of advanced composite colloids made of conducting polymer polyaniline (PANI) and cellulose nanocrystals (CNC) or nanofibrils (CNF). PANI/cellulose particles were prepared using oxidative polymerization of aniline in situ in the presence of CNC or CNF. The type and amount of celluloses (CNC vs CNF) and concentration of precursors (aniline monomer and oxidant) used in the reaction determined properties of the colloidal particles, such as size, morphology and content of PANI. The particles demonstrated intriguing biological characteristics, including no cytotoxicity, antibacterial activity against Staphylococcus aureus and Escherichia coli, antioxidant activity and related immunomodulatory activity. For the first time, such composites were used to successfully stabilize oil-in-water PE with undecane or capric/caprylic triglyceride oils. The properties of the emulsions were determined by the PANI/cellulose particles and oil used. The key finding of the study is the demonstrated ability of PANI/cellulose particles to stabilize PE, as well as the excellent antioxidant activity and ROS scavenging action originating from PANI presence, indicating potential of such systems for use in biomedicine, particularly for wound healing.

Differential Expression of Proteins Associated with Bipolar Disorder as Identified Using the PeptideShaker Software

The prevalence of bipolar disorder (BD) in modern society is growing rapidly, but due to the lack of paraclinical criteria, its differential diagnosis with other mental disorders is somewhat challenging. In this regard, the relevance of proteomic studies is increasing due to the development of methods for processing large data arrays; this contributes to the discovery of protein patterns of pathological processes and the creation of new methods of diagnosis and treatment. It seems promising to search for proteins involved in the pathogenesis of BD in an easily accessible material-blood serum. Sera from BD patients and healthy individuals were purified via affinity chromatography to isolate 14 major proteins and separated using 1D SDS-PAGE. After trypsinolysis, the proteins in the samples were identified via HPLC/mass spectrometry. Mass spectrometric data were processed using the OMSSA and X!Tandem search algorithms using the UniProtKB database, and the results were analyzed using PeptideShaker. Differences in proteomes were assessed via an unlabeled NSAF-based analysis using a two-tailed Bonferroni-adjusted t-test. When comparing the blood serum proteomes of BD patients and healthy individuals, 10 proteins showed significant differences in NSAF values. Of these, four proteins were predominantly present in BD patients with the maximum NSAF value: 14-3-3 protein zeta/delta; ectonucleoside triphosphate diphosphohydrolase 7; transforming growth factor-beta-induced protein ig-h3; and B-cell CLL/lymphoma 9 protein. Further exploration of the role of these proteins in BD is warranted; conducting such studies will help develop new paraclinical criteria and discover new targets for BD drug therapy.

Some structural features of the peptide profile of myelin basic protein-hydrolyzing antibodies in schizophrenic patients

The antibodies of schizophrenic patients that hydrolyze myelin basic protein (MBP) have been actively studied recently, but the mechanism of the catalytic properties of immunoglobulin molecules remains unknown. Determination of specific immunoglobulin sequences associated with the high activity of MBP proteolysis will help to understand the mechanisms of abzyme catalysis. In the course of comparative mass spectrometric analysis of IgG peptides from the blood serum of patients with acute schizophrenia and healthy people, 12 sequences were identified, which were found only in antibodies that hydrolyze MBP. These sequences belong to IgG heavy chains and κ- and λ-type light chains, with eight of them belonging to variable domains. The content of peptides from the variable regions of the light chains does not correlate with the proteolytic activity of IgG to MBP in patients with schizophrenia, whereas for two sequences from the variable regions of the heavy chains (FQ(+0.98)GWVTMTR and *LYLQMN(+0.98)SLR), an increase in activity with increasing their concentration. The results suggest that these sequences may be involved in one way or another in MBP hydrolysis.