Chronic hepatitis B (CHB) remains a major public health problem worldwide, with limited treatment options, but inducing an antiviral response by innate immunity activation may provide a therapeutic alternative. We assessed the cytokine-mediated anti-hepatitis B virus (HBV) potential for stimulating the cyclic GMP-AMP synthase-stimulator of interferon genes (STING) pathway using STING agonists in primary human hepatocytes (PHH) and nonparenchymal liver cells (NPCs). The natural STING agonist, 2',3'-cyclic GMP-AMP, the synthetic analogue 3',3'-c-di(2'F,2'dAMP), and its bis(pivaloyloxymethyl) prodrug had strong indirect cytokine-mediated anti-HBV effects in PHH regardless of HBV genotype.
View Article and Find Full Text PDFThe liver is a complex organ that governs many types of metabolisms, including energy metabolism and other cellular processes. The liver also plays a crucial role in important functions in immunity, and the activity of liver tissue-associated immunity affects the outcome of many liver pathologies. A thorough characterization of the liver immune microenvironment may contribute to a better understanding of immune signaling, the mechanisms of specific immune responses, and even to improved predictions about therapy outcomes.
View Article and Find Full Text PDFStimulator of interferon genes (STING) is an adaptor protein of the cGAS-STING signaling pathway involved in the sensing of cytosolic DNA. It functions as a receptor for cyclic dinucleotides (CDNs) and, upon their binding, mediates cytokine expression and host immunity. Besides naturally occurring CDNs, various synthetic CDNs, such as ADU-S100, have been reported to effectively activate STING and are being evaluated in clinical trials for the treatment of cancer.
View Article and Find Full Text PDFThe cGAS-STING (cyclic GMP-AMP synthase-stimulator of interferon genes) pathway plays a crucial role in inducing an antiviral and antitumor immune response. We studied the effects of synthetic STING agonists on several immune populations and related cytokine production. In comparison with the toll-like receptor 7 (TLR7) agonist, STING agonists induced secretion of a broader proinflammatory cytokine spectrum.
View Article and Find Full Text PDFCyclic dinucleotides (CDNs) are second messengers that bind to the stimulator of interferon genes (STING) and trigger the expression of type I interferons and proinflammatory cytokines. Here we evaluate the activity of 3',3'-c-di(2'F,2'dAMP) and its phosphorothioate analogues against five STING allelic forms in reporter-cell-based assays and rationalize our findings with X-ray crystallography and quantum mechanics/molecular mechanics calculations. We show that the presence of fluorine in the 2' position of 3',3'-c-di(2'F,2'dAMP) improves its activity not only against the wild type (WT) but also against REF and Q STING.
View Article and Find Full Text PDFBackground: Immunosuppressive cell-based therapy is a recent strategy for controlling Graft--Host Disease (GvHD). Such cells ought to maintain their suppressive function in inflammatory conditions and in the presence of immunosuppressive agents currently used in allogeneic hematopoietic cell transplantation (allo-HCT). Moreover, these therapies should not diminish the benefits of allo-HCT, the Graft--Leukemia (GvL) effect.
View Article and Find Full Text PDFProstate cancer is one of the most prominent cancers diagnosed in males. Contrasting with other cancer types, glucose utilization is not increased in prostate carcinoma cells as they employ different metabolic adaptations involving mitochondria as a source of energy and intermediates required for rapid cell growth. In this regard, prostate cancer cells were associated with higher activity of mitochondrial glycerol-3-phosphate dehydrogenase (mGPDH), the key rate limiting component of the glycerophosphate shuttle, which connects mitochondrial and cytosolic processes and plays significant role in cellular bioenergetics.
View Article and Find Full Text PDFCyclic dinucleotides are second messengers in the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway, which plays an important role in recognizing tumor cells and viral or bacterial infections. They bind to the STING adaptor protein and trigger expression of cytokines via TANK binding kinase 1 (TBK1)/interferon regulatory factor 3 (IRF3) and inhibitor of nuclear factor-κB (IκB) kinase (IKK)/nuclear factor-κB (NFκB) signaling cascades. In this work, we describe an enzymatic preparation of 2'-5',3'-5'-cyclic dinucleotides (2'3'CDNs) with use of cyclic GMP-AMP synthases (cGAS) from human, mouse, and chicken.
View Article and Find Full Text PDFBiogenesis of FF ATP synthase, the key enzyme of mitochondrial energy provision, depends on transmembrane protein 70 (TMEM70), localized in the inner mitochondrial membrane of higher eukaryotes. TMEM70 absence causes severe ATP-synthase deficiency and leads to a neonatal mitochondrial encephalocardiomyopathy in humans. However, the exact biochemical function of TMEM70 remains unknown.
View Article and Find Full Text PDFMetformin is the most widely prescribed treatment of hyperglycemia and type II diabetes since 1970s. During the last 15 years, its popularity increased due to epidemiological evidence, that metformin administration reduces incidence of cancer. However, despite the ongoing effort of many researchers, the molecular mechanisms underlying antihyperglycemic or antineoplastic action of metformin remain elusive.
View Article and Find Full Text PDFAnn Allergy Asthma Immunol
November 2016
Background: The most emblematic members of Urticaceae at allergic risk level are wall pellitories (Parietaria), whereas nettle (Urtica) pollen is considered as poorly allergenic. No allergen from nettle pollen has yet been characterized, whereas 4 are listed for Parietaria pollen by the International Union of Immunological Societies. Clinical and biological profiles of 2 adult men who developed symptoms against nettle pollen and/or leaves were studied.
View Article and Find Full Text PDFImmune infertility, in terms of reproductive failure, has become a serious health issue involving approximately 1 out of 5 couples at reproductive age. Semen that is defined as a complex fluid containing sperm, cellular vesicles and other cells and components, could sensitize the female genital tract. The immune rejection of male semen in the female reproductive tract is explained as the failure of natural tolerance leading to local and/or systemic immune response.
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