Publications by authors named "Pozdeev V"

Modeling tumor metabolism in vitro remains challenging. Here, we used galactose as an in vitro tool compound to mimic glycolytic limitation. In contrast to the established idea that high glycolytic flux reduces pyruvate kinase isozyme M2 (PKM2) activity to support anabolic processes, we have discovered that glycolytic limitation also affects PKM2 activity.

View Article and Find Full Text PDF

Metabolic rewiring is essential for cancer onset and progression. We previously showed that one-carbon metabolism-dependent formate production often exceeds the anabolic demand of cancer cells, resulting in formate overflow. Furthermore, we showed that increased extracellular formate concentrations promote the in vitro invasiveness of glioblastoma cells.

View Article and Find Full Text PDF

Fibroblasts have a considerable functional and molecular heterogeneity and can play various roles in the tumor microenvironment. Here we identify a pro-tumorigenic IL1R1, IL-1-high-signaling subtype of fibroblasts, using multiple colorectal cancer (CRC) patient single cell sequencing datasets. This subtype of fibroblasts is linked to T cell and macrophage suppression and leads to increased cancer cell growth in 3D co-culture assays.

View Article and Find Full Text PDF

Metastasis is the most common cause of death in cancer patients. Canonical drugs target mainly the proliferative capacity of cancer cells, which leaves slow-proliferating, persistent cancer cells unaffected. Metabolic determinants that contribute to growth-independent functions are still poorly understood.

View Article and Find Full Text PDF

The gut microbiome is a key player in the immunomodulatory and protumorigenic microenvironment during colorectal cancer (CRC), as different gut-derived bacteria can induce tumour growth. However, the crosstalk between the gut microbiome and the host in relation to tumour cell metabolism remains largely unexplored. Here we show that formate, a metabolite produced by the CRC-associated bacterium Fusobacterium nucleatum, promotes CRC development.

View Article and Find Full Text PDF

Elucidating key factors that regulate immune-mediated pathology is critical for developing improved strategies to treat autoimmune disease and cancer. NK cells can exhibit regulatory functions against CD8 T cells following viral infection. Here we show that while low doses of lymphocytic choriomeningitis virus (LCMV-WE) can readily induce strong CD8 T cell responses and diabetes in mice expressing the LCMV glycoprotein on β-islet cells (RIP-GP mice), hyperglycemia does not occur after infection with higher doses of LCMV.

View Article and Find Full Text PDF

Unlabelled: In solid tumors, cancer stem cells (CSCs) or tumor-initiating cells (TICs) are often found in hypoxic niches. Nevertheless, the influence of hypoxia on TICs is poorly understood. Using previously established, TIC-enrichedpatient-derived colorectal cancer (CRC) cultures, we show that hypoxia increases the self-renewal capacity of TICs while inducing proliferation arrest in their more differentiated counterpart cultures.

View Article and Find Full Text PDF

Objective: To study the causes of recurrent postoperative ventral hernias and methods for their prevention.

Material And Methods: There were 58 patients with recurrent postoperative ventral hernias after various methods of abdominal wall repair for the period 2005-2017.

Results: The main causes of recurrent postoperative ventral hernias were identified.

View Article and Find Full Text PDF

Cancer cells utilize multiple mechanisms to evade and suppress anticancer immune responses creating a "cold" immunosuppressive tumor microenvironment. Oncolytic virotherapy is emerging as a promising approach to revert tumor immunosuppression and enhance the efficacy of other forms of immunotherapy. Growing evidence indicates that oncolytic viruses (OVs) act in a multimodal fashion, inducing immunogenic cell death and thereby eliciting robust anticancer immune responses.

View Article and Find Full Text PDF

Immune responses are critical for defense against pathogens. However, prolonged viral infection can result in defective T cell immunity, leading to chronic viral infection. We studied immune activation in response to arenavirus infection during cholestasis using bile duct ligation (BDL).

View Article and Find Full Text PDF

Innate immune activation is essential to mount an effective antiviral response and to prime adaptive immunity. Although a crucial role of CD169 cells during vesicular stomatitis virus (VSV) infections is increasingly recognized, factors regulating CD169 cells during viral infections remain unclear. Here, we show that tumor necrosis factor is produced by CD11b Ly6C Ly6G cells following infection with VSV.

View Article and Find Full Text PDF

The devastating consequences of hepatic failure include hepatic encephalopathy, a severe, life threatening impairment of neuronal function. Hepatic encephalopathy is caused by impaired hepatic clearance of NH. Cellular NH uptake is accomplished mainly by the Na,K,2Cl cotransporter.

View Article and Find Full Text PDF

Background/aims: Viral infections represent a global health problem with the need for new viral therapies and better understanding of the immune response during infection. The most immediate and potent anti-viral defense mechanism is the production of type I interferon (IFN-I) which are activated rapidly following recognition of viral infection by host pathogen recognition receptors (PRR). The mechanisms of innate cellular signaling downstream of PRR activation remain to be fully understood.

View Article and Find Full Text PDF

Urea cycle defects and acute or chronic liver failure are linked to systemic hyperammonemia and often result in cerebral dysfunction and encephalopathy. Although an important role of the liver in ammonia metabolism is widely accepted, the role of ammonia metabolizing pathways in the liver for maintenance of whole-body ammonia homeostasis in vivo remains ill-defined. Here, we show by generation of liver-specific Gln synthetase (GS)-deficient mice that GS in the liver is critically involved in systemic ammonia homeostasis in vivo.

View Article and Find Full Text PDF

B cells are essential for antiviral immune defence because they produce neutralizing antibodies, present antigen and maintain the lymphoid architecture. Here we show that intrinsic signalling of CEACAM1 is essential for generating efficient B-cell responses. Although CEACAM1 exerts limited influence on the proliferation of B cells, expression of CEACAM1 induces survival of proliferating B cells via the BTK/Syk/NF-κB-axis.

View Article and Find Full Text PDF

STAT3 is a critical transcription factor activated downstream of cytokine signaling and is integral for the function of multiple immune cell types. Human mutations in STAT3 cause primary immunodeficiency resulting in impaired control of a variety of infections, including reactivation of latent viruses. In this study, we investigate how T-cell functions of STAT3 contribute to responses to viral infection by inducing chronic lymphocytic choriomeningitis virus (LCMV) infection in mice lacking STAT3 specifically in T cells.

View Article and Find Full Text PDF

CD8(+) T-cell functions are critical for preventing chronic viral infections by eliminating infected cells. For healthy immune responses, beneficial destruction of infected cells must be balanced against immunopathology resulting from collateral damage to tissues. These processes are regulated by factors controlling CD8(+) T-cell function, which are still incompletely understood.

View Article and Find Full Text PDF

Background And Study Aims: In 38-80% patients with suspicion to choledocholithiasis were no stones in common bile duct (CBD) after endoscopic retrograde cholangiopancreatography (ERCP). ERCP is not safe procedure and has a risk of complications ranging 4-15%. The aim of our study was to estimate the diagnostic value and safety of endoscopic ultrasound (EUS) in CBD stones diagnosis.

View Article and Find Full Text PDF

Rapid activation of immune responses is necessary for antibacterial defense, but excessive immune activation can result in life-threatening septic shock. Understanding how these processes are balanced may provide novel therapeutic potential in treating inflammatory disease. Fc receptors are crucial for innate immune activation.

View Article and Find Full Text PDF

Cluster of differentiation (CD)8(+) T cells are like a double edged sword during chronic viral infections because they not only promote virus elimination but also induce virus-mediated immunopathology. Elevated levels of reactive oxygen species (ROS) have been reported during virus infections. However, the role of ROS in T-cell-mediated immunopathology remains unclear.

View Article and Find Full Text PDF

The vaporization enthalpies of a series of heterocyclic compounds some suspected of showing evidence of a higher degree of self-association in comparison to many other nitrogen heterocycles have been measured both by correlation gas chromatography (CGC) and for comparison by transpiration. The compounds share some structural similarities. They include 2- and 4-(N,N-dimethylamino)pyridine, 1,5-diazabicyclo[4.

View Article and Find Full Text PDF