Publications by authors named "Gorka O"

Article Synopsis
  • Mitochondria play complex roles in two different cell death pathways: apoptosis and pyroptosis, particularly regarding NLRP3 inflammasome activation, but their exact mechanisms are not well understood.
  • The study found that activating NLRP3 while inhibiting apoptosis occurs when cells are under stress from various stimuli like nigericin and viruses, as these activators affect mitochondrial function rather than just triggering inflammasome activation.
  • NLRP3 activation needs a combination of signals—one from disrupted mitochondrial processes and another from specific NLRP3 activators—suggesting that both oxidative phosphorylation inhibition and apoptosis suppression influence cell fate.
View Article and Find Full Text PDF

Photoimmunotherapy (PIT) combines the specificity of antibodies with the cytotoxicity of light activatable photosensitizers (PS) and is a promising new cancer therapy. We designed and synthesized, in a highly convergent manner, the silicon phthalocyanine dye WB692-CB2, which is novel for being the first light-activatable PS that can be directly conjugated via a maleimide linker to cysteines. In the present study we conjugated WB692-CB2 to a humanized antibody with engineered cysteines in the heavy chains that specifically targets the prostate-specific membrane antigen (PSMA).

View Article and Find Full Text PDF

3' untranslated regions (3' UTRs) are critical elements of messenger RNAs, as they contain binding sites for RNA-binding proteins (RBPs) and microRNAs that affect various aspects of the RNA life cycle including transcript stability and cellular localization. In response to T cell receptor activation, T cells undergo massive expansion during the effector phase of the immune response and dynamically modify their 3' UTRs. Whether this serves to directly regulate the abundance of specific mRNAs or is a secondary effect of proliferation remains unclear.

View Article and Find Full Text PDF
Article Synopsis
  • Differentiated podocytes are sensitive to oxidative stress and cellular waste, with their loss indicating renal disease progression and aging.
  • The study identifies ARFIP2 as a crucial regulator of autophagy and mitophagy in podocytes, utilizing both in vitro (human cell lines) and in vivo (mouse models) methods to investigate its role.
  • Findings reveal that ARFIP2 deficiency hampers autophagy, disrupts mitochondrial function, and exacerbates kidney damage in diabetic mice, highlighting its importance in podocyte health and renal maintenance.
View Article and Find Full Text PDF
Article Synopsis
  • Exposure to fine particulate matter (PM) from air pollution leads to respiratory and cardiovascular issues by activating the NLRP3 inflammasome, which triggers inflammation and release of IL-1β, a key inflammatory cytokine.
  • The activation of the inflammasome is dependent on the amount and type of PM, with Residual Oil Fly Ash (ROFA) being particularly effective in inducing IL-1β release, while other PM types were less effective.
  • The study reveals that mechanisms like lysosomal rupture and mitochondrial dysfunction contribute to IL-1β release, highlighting the complex interplay of cellular damage and immune response to specific air pollutants like ROFA.
View Article and Find Full Text PDF

Inositol pyrophosphates (PP-InsPs) are energetic signaling molecules with important functions in mammals. As their biosynthesis depends on ATP concentration, PP-InsPs are tightly connected to cellular energy homeostasis. Consequently, an increasing number of studies involve PP-InsPs in metabolic disorders, such as type 2 diabetes, aspects of tumorigenesis, and hyperphosphatemia.

View Article and Find Full Text PDF

The skin needs to balance tolerance of colonizing microflora with rapid detection of potential pathogens. Flexible response mechanisms would seem most suitable to accommodate the dynamic challenges of effective antimicrobial defense and restoration of tissue homeostasis. Here, we dissected macrophage-intrinsic mechanisms and microenvironmental cues that tune macrophage signaling in localized skin infection with the colonizing and opportunistic pathogen Early in skin infection, the cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF) produced by γδ T cells and hypoxic conditions within the dermal microenvironment diverted macrophages away from a homeostatic M-CSF- and hypoxia-inducible factor 1α (HIF-1α)-dependent program.

View Article and Find Full Text PDF
Article Synopsis
  • Exhausted T cells, which are important for fighting viruses, are found in people with chronic hepatitis B and C infections.
  • Researchers studied how metabolism affects these T cells by looking at samples from infected patients and using a mouse model.
  • They found that different states of T cell exhaustion are linked to changes in their metabolism, and a protein called enolase plays a key role in regulating how well these T cells work.
View Article and Find Full Text PDF

Inflammasomes are intracellular protein complexes that promote an inflammatory host defense in response to pathogens and damaged or neoplastic tissues and are implicated in inflammatory disorders and therapeutic-induced toxicity. We investigated the mechanisms of activation for inflammasomes nucleated by NOD-like receptor (NLR) protiens. A screen of a small-molecule library revealed that several tyrosine kinase inhibitors (TKIs)-including those that are clinically approved (such as imatinib and crizotinib) or are in clinical trials (such as masitinib)-activated the NLRP3 inflammasome.

View Article and Find Full Text PDF

Aberrant angiogenesis is a hallmark of cardiovascular and retinal neovascular disease. The STAT3 signaling pathway represents a potential pharmacological target for these diseases due to its impact on angiogenesis. Surprisingly, some STAT3 activators, such as the IL-6 cytokine family member oncostatin M (OSM), enhance angiogenesis, whereas others, such as ciliary neurotropic factor (CNTF), reduce it.

View Article and Find Full Text PDF

Tissue-resident macrophages (TRMs) perform organ-specific functions that are dependent on factors such as hematopoietic origin, local environment, and biological influences. A diverse range of culture systems have been developed to decipher TRM functions, including bone marrow-derived macrophages (BMDMs), induced pluripotent stem cell (iPSC)-derived TRMs, or immortalized cell lines. However, despite the usefulness of such systems, there are notable limitations.

View Article and Find Full Text PDF

B-cell precursor acute lymphoblastic leukemias (B-ALL) are characterized by the activation of signaling pathways, which are involved in survival and proliferation of leukemia cells. Using an unbiased shRNA library screen enriched for targeting signaling pathways, we identified MTOR as the key gene on which human B-ALL E2A-PBX1 RCH-ACV cells are dependent. Using genetic and pharmacologic approaches, we investigated whether B-ALL cells depend on MTOR upstream signaling pathways including PI3K/AKT and the complexes MTORC1 or MTORC2 for proliferation and survival in vitro and in vivo.

View Article and Find Full Text PDF

MicroRNAs are key regulators of the cardiac response to injury. MiR-100 has recently been suggested to be involved in different forms of heart failure, but functional studies are lacking. In the present study, we examined the impact of transgenic miR-100 overexpression on cardiac structure and function during physiological aging and pathological pressure-overload-induced heart failure in mice after transverse aortic constriction surgery.

View Article and Find Full Text PDF

The NLRP3 inflammasome is an important player in innate immunity and pathogenic inflammation. Numerous studies have implicated it in sensing endogenous danger signals, yet the precise mechanisms remain unknown. Here, we review the current knowledge on the organismal and cellular metabolic triggers engaging NLRP3, and the mechanisms involved in integrating the diverse signals.

View Article and Find Full Text PDF

The mechanical environment of cardiac cells changes continuously and undergoes major alterations during diseases. Most cardiac diseases, including atrial fibrillation, are accompanied by fibrosis which can impair both electrical and mechanical function of the heart. A key characteristic of fibrotic tissue is excessive accumulation of extracellular matrix, leading to increased tissue stiffness.

View Article and Find Full Text PDF

Loss of lymphocytes, particularly T cell apoptosis, is a central pathological event after severe tissue injury that is associated with increased susceptibility for life-threatening infections. The precise immunological mechanisms leading to T cell death after acute injury are largely unknown. Here, we identified a monocyte-T cell interaction driving bystander cell death of T cells in ischemic stroke and burn injury.

View Article and Find Full Text PDF

Amino acids are integral components of cancer metabolism. The non-essential amino acid asparagine supports the growth and survival of various cancer cell types. Here, different mass spectrometry approaches were employed to identify lower aspartate levels, higher aspartate/glutamine ratios and lower tricarboxylic acid (TCA) cycle metabolite levels in asparagine-deprived sarcoma cells.

View Article and Find Full Text PDF

Diversity-oriented synthesis (DOS) has become a powerful synthetic tool that facilitates the construction of nature-inspired and privileged chemical space, particularly for sp -rich non-flat scaffolds, which are needed for phenotypic screening campaigns. These diverse compound collections led to the discovery of novel chemotypes that can modulate the protein function in underrepresented biological space. In this context, starting material-driven DOS is one of the most important tools used to build diverse compound libraries with rich stereochemical and scaffold diversity.

View Article and Find Full Text PDF

Nutrient uptake is essential for survival of organisms, and carbohydrates serve as a crucial carbon and energy source for most microorganisms. Given the importance of mycobacteria as human pathogens a detailed knowledge of carbohydrate uptake transporters is highly desirable, but currently available information is severely limited and mainly based on in silico analyses. Moreover, there is only very little data available on the in vitro characterization of carbohydrate transporters from mycobacterial species.

View Article and Find Full Text PDF

The transcription factor Foxp1 is critical for early B cell development. Despite frequent deregulation of Foxp1 in B cell lymphoma, the physiological functions of Foxp1 in mature B cells remain unknown. Here, we used conditional gene targeting in the B cell lineage and report that Foxp1 disruption in developing and mature B cells results in reduced numbers and frequencies of follicular and B-1 B cells and in impaired antibody production upon T cell-independent immunization in vivo.

View Article and Find Full Text PDF

Inflammasomes activate the protease caspase-1, which cleaves interleukin-1β and interleukin-18 to generate the mature cytokines and controls their secretion and a form of inflammatory cell death called pyroptosis. By generating mice expressing enzymatically inactive caspase-1, we provide genetic evidence that caspase-1 protease activity is required for canonical IL-1 secretion, pyroptosis, and inflammasome-mediated immunity. In caspase-1-deficient cells, caspase-8 can be activated at the inflammasome.

View Article and Find Full Text PDF

The impact of epigenetics on the differentiation of memory T (Tmem) cells is poorly defined. We generated deep epigenomes comprising genome-wide profiles of DNA methylation, histone modifications, DNA accessibility, and coding and non-coding RNA expression in naive, central-, effector-, and terminally differentiated CD45RA CD4 Tmem cells from blood and CD69 Tmem cells from bone marrow (BM-Tmem). We observed a progressive and proliferation-associated global loss of DNA methylation in heterochromatic parts of the genome during Tmem cell differentiation.

View Article and Find Full Text PDF

Imiquimod is a small-molecule ligand of Toll-like receptor-7 (TLR7) that is licensed for the treatment of viral infections and cancers of the skin. Imiquimod has TLR7-independent activities that are mechanistically unexplained, including NLRP3 inflammasome activation in myeloid cells and apoptosis induction in cancer cells. We investigated the mechanism of inflammasome activation by imiquimod and the related molecule CL097 and determined that K efflux was dispensable for NLRP3 activation by these compounds.

View Article and Find Full Text PDF

The design and development of novel biological drugs are among the most exciting new areas of biotechnology which are gaining the attention of scientists. In the last few decades several fabrication processes have been proposed and developed for the production of recombinant growth factors. However, traditional production processes have several limitations in terms of scale- up, cost-efficiency and purity grade of the proteins.

View Article and Find Full Text PDF