PI3Kγ inhibition circumvents inflammation and vascular leak in SARS-CoV-2 and other infections.

Virulent infectious agents such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and methicillin-resistant Staphylococcus aureus (MRSA) induce tissue damage that recruits neutrophils, monocyte, and macrophages, leading to T cell exhaustion, fibrosis, vascular leak, epithelial cell depletion, and fatal organ damage. Neutrophils, monocytes, and macrophages recruited to pathogen-infected lungs, including SARS-CoV-2-infected lungs, express phosphatidylinositol 3-kinase gamma (PI3Kγ), a signaling protein that coordinates both granulocyte and monocyte trafficking to diseased tissues and immune-suppressive, profibrotic transcription in myeloid cells. PI3Kγ deletion and inhibition with the clinical PI3Kγ inhibitor eganelisib promoted survival in models of infectious diseases, including SARS-CoV-2 and MRSA, by suppressing inflammation, vascular leak, organ damage, and cytokine storm. These results demonstrate essential roles for PI3Kγ in inflammatory lung disease and support the potential use of PI3Kγ inhibitors to suppress inflammation in severe infectious diseases.

JAK inhibition enhances checkpoint blockade immunotherapy in patients with Hodgkin lymphoma.

Unleashing antitumor T cell activity by checkpoint inhibitor immunotherapy is effective in cancer patients, but clinical responses are limited. Cytokine signaling through the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway correlates with checkpoint immunotherapy resistance. We report a phase I clinical trial of the JAK inhibitor ruxolitinib with anti-PD-1 antibody nivolumab in Hodgkin lymphoma patients relapsed or refractory following checkpoint inhibitor immunotherapy. The combination yielded a best overall response rate of 53% (10/19). Ruxolitinib significantly reduced neutrophil-to-lymphocyte ratios and percentages of myeloid suppressor cells but increased numbers of cytokine-producing T cells. Ruxolitinib rescued the function of exhausted T cells and enhanced the efficacy of immune checkpoint blockade in preclinical solid tumor and lymphoma models. This synergy was characterized by a switch from suppressive to immunostimulatory myeloid cells, which enhanced T cell division.

Targeted desialylation and cytolysis of tumour cells by fusing a sialidase to a bispecific T-cell engager.

Bispecific T-cell engagers (BiTEs) bring together tumour cells and cytotoxic T cells by binding to specific cell-surface tumour antigens and T-cell receptors, and have been clinically successful for the treatment of B-cell malignancies. Here we show that a BiTE-sialidase fusion protein enhances the susceptibility of solid tumours to BiTE-mediated cytolysis of tumour cells via targeted desialylation-that is, the removal of terminal sialic acid residues on glycans-at the BiTE-induced T-cell-tumour-cell interface. In xenograft and syngeneic mouse models of leukaemia and of melanoma and breast cancer, and compared with the parental BiTE molecules, targeted desialylation via the BiTE-sialidase fusion proteins enhanced the formation of immunological synapses, T-cell activation and T-cell-mediated tumour-cell cytolysis in the presence of the target antigen. The targeted desialylation of tumour cells may enhance the potency of therapies relying on T-cell engagers.

Transient EZH2 suppression by Tazemetostat during in vitro expansion maintains T cell stemness and improves adoptive T cell therapy.

The histone methyltransferase enhancer of zeste homolog 2 (EZH2)-mediated epigenetic regulation of T cell differentiation in acute infection has been extensively investigated. However, the role of EZH2 in T cell exhaustion remains under-explored. Here, using in vitro exhaustion models, we demonstrated that transient inhibition of EZH2 in T cells before the phenotypic onset of exhaustion with a clinically approved inhibitor, Tazemetastat, delayed their dysfunctional progression and maintained T cell stemness and polyfunctionality while having no negative impact on cell proliferation. Tazemetestat induced T cell epigenetic reprogramming and increased the expression of the self-renewing T cell transcription factor TCF1 by reducing its promoter H3K27 methylation preferentially in rapidly dividing T cells. In a murine melanoma model, T cells pre-treated with tazemetastat exhibited a superior response to anti-PD-1 blockade therapy after adoptive transfer. Collectively, these data unveil the potential of transient epigenetic reprogramming as a potential intervention to be combined with checkpoint blockade for immune therapy.

B cell-derived IL-27 promotes control of persistent LCMV infection.

Recent studies have identified a critical role for B cell-produced cytokines in regulating both humoral and cellular immunity. Here, we show that B cells are an essential source of interleukin-27 (IL-27) during persistent lymphocytic choriomeningitis virus (LCMV) clone 13 (Cl-13) infection. By using conditional knockout mouse models with specific IL-27p28 deletion in B cells, we observed that B cell-derived IL-27 promotes survival of virus-specific CD4 T cells and supports functions of T follicular helper (Tfh) cells. Mechanistically, B cell-derived IL-27 promotes CD4 T cell function, antibody class switch, and the ability to control persistent LCMV infection. Deletion of IL-27ra in T cells demonstrated that T cell-intrinsic IL-27R signaling is essential for viral control, optimal CD4 T cell responses, and antibody class switch during persistent LCMV infection. Collectively, our findings identify a cellular mechanism whereby B cell-derived IL-27 drives antiviral immunity and antibody responses through IL-27 signaling on T cells to promote control of LCMV Cl-13 infection.

Lightweight Concretes with Improved Water and Water Vapor Transport for Remediation of Damp Induced Buildings.

Most of the historical and old building stock in Europe are constructed from masonry, when brick, stones, or their combination are bound with traditional mortars. Rising damp, due to accompanying effects, is the main factor influencing the quality of indoor climate as well as having an important impact on the durability of masonry structures. In this study, new types of lightweight concrete with waste aggregate content as a suitable material for remediation of damp damaged masonries were designed and tested. Alternative aggregate served as silica sand substitution in the range of 0-100 vol.%. Basic structural properties, mechanical resistance, water, and water vapor transport properties were measured after 28 days of water curing and were compared with dense reference concrete and with traditional masonry materials as well. Moreover, the porous structure of produced concretes and changes caused by usage of alternative aggregate usage were evaluated with the mercury intrusion porosimetry (MIP) technique. Obtained experimental data showed the suitability of modified concretes with 25-50 vol.% of waste aggregate content to ensure acceptable strength and hydric properties, and these properties were found to be comparable with masonry structures and materials used in the past.

IFNAR1 signaling in NK cells promotes persistent virus infection.

Inhibition of type 1 interferon (IFN-I) signaling promotes the control of persistent virus infection, but the underlying mechanisms remain poorly understood. Here, we report that genetic ablation of Ifnar1 specifically in natural killer (NK) cells led to elevated numbers of T follicular helper cells, germinal center B cells, and plasma cells and improved antiviral T cell function, resulting in hastened virus clearance that was comparable to IFNAR1 neutralizing antibody treatment. Antigen-specific B cells and antiviral antibodies were essential for the accelerated control of LCMV Cl13 infection following IFNAR1 blockade. IFNAR1 signaling in NK cells promoted NK cell function and general killing of antigen-specific CD4 and CD8 T cells. Therefore, inhibition of IFN-I signaling in NK cells enhances CD4 and CD8 T cell responses, promotes humoral immune responses, and thereby facilitates the control of persistent virus infection.

Discovery of Small Molecules for the Reversal of T Cell Exhaustion.

Inhibitory receptors (IRs) function as critical regulators of immune responses by tempering T cell activity. In humans, several persisting viruses as well as cancers exploit IR signaling by upregulating IR ligands, resulting in suppression of T cell function (i.e., exhaustion). This allows escape from immune surveillance and continuation of disease. Here, we report the design, implementation, and results of a phenotypic high-throughput screen for molecules that modulate CD8+ T cell activity. We identify 19 compounds from the ReFRAME drug-repurposing collection that restore cytokine production and enhance the proliferation of exhausted T cells. Analysis of our top hit, ingenol mebutate, a protein kinase C (PKC) inducing diterpene ester, reveals a role for this molecule in overriding the suppressive signaling cascade mediated by IR signaling on T cells. Collectively, these results demonstrate a disease-relevant methodology for identifying modulators of T cell function and reveal new targets for immunotherapy.

IL-27 promotes the expansion of self-renewing CD8+ T cells in persistent viral infection.

Chronic infection and cancer are associated with suppressed T cell responses in the presence of cognate antigen. Recent work identified memory-like CXCR5+ TCF1+ CD8+ T cells that sustain T cell responses during persistent infection and proliferate upon anti-PD1 treatment. Approaches to expand these cells are sought. We show that blockade of interferon type 1 (IFN-I) receptor leads to CXCR5+ CD8+ T cell expansion in an IL-27- and STAT1-dependent manner. IFNAR1 blockade promoted accelerated cell division and retention of TCF1 in virus-specific CD8+ T cells. We found that CD8+ T cell-intrinsic IL-27 signaling safeguards the ability of TCF1hi cells to maintain proliferation and avoid terminal differentiation or programmed cell death. Mechanistically, IL-27 endowed rapidly dividing cells with IRF1, a transcription factor that was required for sustained division in a cell-intrinsic manner. These findings reveal that IL-27 opposes IFN-I to uncouple effector differentiation from cell division and suggest that IL-27 signaling could be exploited to augment self-renewing T cells in chronic infections and cancer.

Progression of type 1 diabetes from the prediabetic stage is controlled by interferon-α signaling.

Blockade of IFN-α but not IFN-ß signaling using either an antibody or a selective S1PR1 agonist, CYM-5442, prevented type 1 diabetes (T1D) in the mouse Rip-LCMV T1D model. First, treatment with antibody or CYM-5442 limited the migration of autoimmune "antiself" T cells to the external boundaries around the islets and prevented their entry into the islets so they could not be positioned to engage, kill, and thus remove insulin-producing ß cells. Second, CYM-5442 induced an exhaustion signature in antiself T cells by up-regulating the negative immune regulator receptor genes Pdcd1, Lag3, Ctla4, Tigit, and Btla, thereby limiting their killing ability. By such means, insulin production was preserved and glucose regulation maintained, and a mechanism for S1PR1 immunomodulation described.

Polemics on Ethical Aspects in the Compost Business.

This paper focuses on compost use in overpasses and underpasses for wild animals over roads and other similar linear structures. In this context, good quality of compost may result in faster and more resistant vegetation cover during the year. Inter alia, this can be interpreted also as reduction of damage and saving lives. There are millions of tones of plant residue produced every day worldwide. These represent prospective business for manufacturers of compost additives called "accelerators". The opinions of the sale representatives' with regards to other alternatives of biowaste utilization and their own products were reviewed. The robust analyzes of several "accelerated" composts revealed that the quality was generally low. Only two accelerated composts were somewhat similar in quality to the blank sample that was produced according to the traditional procedure. Overlaps between the interests of decision makers on future soil fertility were weighed against the preferences on short-term profit. Possible causes that allowed the boom of these underperforming products and the possible consequences are also discussed. Conclusions regarding the ethical concerns on how to run businesses with products whose profitability depends on weaknesses in the legal system and customer unawareness are to follow.

Aspp1: A Guardian of Hematopoietic Stem Cell Integrity.

Eliminating hematopoietic stem cells (HSCs) with DNA damage is necessary to maintain the homeostasis of HSCs, but the mechanisms underlying this apoptotic elimination are unclear. Now in Cell Stem Cell, Yamashita et al. (2015) show that Aspp1 coordinates with p53 to protect HSC pool integrity, guarding against hematological malignancies.

ASPP2 links the apical lateral polarity complex to the regulation of YAP activity in epithelial cells.

The Hippo pathway, by tightly controlling the phosphorylation state and activity of the transcription cofactors YAP and TAZ is essential during development and tissue homeostasis whereas its deregulation may lead to cancer. Recent studies have linked the apicobasal polarity machinery in epithelial cells to components of the Hippo pathway and YAP and TAZ themselves. However the molecular mechanism by which the junctional pool of YAP proteins is released and activated in epithelial cells remains unknown. Here we report that the tumour suppressor ASPP2 forms an apical-lateral polarity complex at the level of tight junctions in polarised epithelial cells, acting as a scaffold for protein phosphatase 1 (PP1) and junctional YAP via dedicated binding domains. ASPP2 thereby directly induces the dephosphorylation and activation of junctional YAP. Collectively, this study unearths a novel mechanistic paradigm revealing the critical role of the apical-lateral polarity complex in activating this localised pool of YAP in vitro, in epithelial cells, and in vivo, in the murine colonic epithelium. We propose that this mechanism may commonly control YAP functions in epithelial tissues.

ASPP2 controls epithelial plasticity and inhibits metastasis through ß-catenin-dependent regulation of ZEB1.

Epithelial to mesenchymal transition (EMT), and the reverse mesenchymal to epithelial transition (MET), are known examples of epithelial plasticity that are important in kidney development and cancer metastasis. Here we identify ASPP2, a haploinsufficient tumour suppressor, p53 activator and PAR3 binding partner, as a molecular switch of MET and EMT. ASPP2 contributes to MET in mouse kidney in vivo. Mechanistically, ASPP2 induces MET through its PAR3-binding amino-terminus, independently of p53 binding. ASPP2 prevents ß-catenin from transactivating ZEB1, directly by forming an ASPP2-ß-catenin-E-cadherin ternary complex and indirectly by inhibiting ß-catenin's N-terminal phosphorylation to stabilize the ß-catenin-E-cadherin complex. ASPP2 limits the pro-invasive property of oncogenic RAS and inhibits tumour metastasis in vivo. Reduced ASPP2 expression results in EMT, and is associated with poor survival in hepatocellular carcinoma and breast cancer patients. Hence, ASPP2 is a key regulator of epithelial plasticity that connects cell polarity to the suppression of WNT signalling, EMT and tumour metastasis.

A code for RanGDP binding in ankyrin repeats defines a nuclear import pathway.

Regulation of nuclear import is fundamental to eukaryotic biology. The majority of nuclear import pathways are mediated by importin-cargo interactions. Yet not all nuclear proteins interact with importins, necessitating the identification of a general importin-independent nuclear import pathway. Here, we identify a code that determines importin-independent nuclear import of ankyrin repeats (ARs), a structural motif found in over 250 human proteins with diverse functions. AR-containing proteins (ARPs) with a hydrophobic residue at the 13th position of two consecutive ARs bind RanGDP efficiently, and consequently enter the nucleus. This code, experimentally tested in 17 ARPs, predicts the nuclear-cytoplasmic localization of over 150 annotated human ARPs with high accuracy and is acquired by the most common familial melanoma-associated CDKN2A mutation, leading to nuclear accumulation of mutant p16ink4a. The RaDAR (RanGDP/AR) pathway represents a general importin-independent nuclear import pathway and is frequently used by AR-containing transcriptional regulators, especially those regulating NF-κB/p53.

Chronic Obstructive Pulmonary Disease: official diagnosis and treatment guidelines of the Czech Pneumological and Phthisiological Society; a novel phenotypic approach to COPD with patient-oriented care.

BACKGROUND: COPD is a global concern. Currently, several sets of guidelines, statements and strategies to managing COPD exist around the world. METHODS: The Czech Pneumological and Phthisiological Society (CPPS) has commissioned an Expert group to draft recommended guidelines for the management of stable COPD. Subsequent revisions were further discussed at the National Consensus Conference (NCC). Reviewers' comments contributed to the establishment of the document's final version. DIAGNOSIS: The hallmark of the novel approach to COPD is the integrated evaluation of the patient's lung functions, symptoms, exacerbations and identifications of clinical phenotype(s). The CPPS defines 6 clinically relevant phenotypes: frequent exacerbator, COPD-asthma overlap, COPD-bronchiectasis overlap, emphysematic phenotype, bronchitic phenotype and pulmonary cachexia phenotype. TREATMENT: Treatment recommendations can be divided into four steps. 1(st) step = Risk exposure elimination: reduction of smoking and environmental tobacco smoke (ETS), decrease of home and occupational exposure risks. 2(nd) step = Standard treatment: inhaled bronchodilators, regular physical activity, pulmonary rehabilitation, education, inhalation training, comorbidity treatment, vaccination. 3(rd) step = Phenotype-specific therapy: PDE4i, ICS+LABA, LVRS, BVR, AAT augmentation, physiotherapy, mucolytic, ABT. 4(th) step = Care for respiratory insufficiency and terminal COPD: LTOT, lung transplantation, high intensity-NIV and palliative care. CONCLUSION: Optimal treatment of COPD patients requires an individualised, multidisciplinary approach to the patient's symptoms, clinical phenotypes, needs and wishes. The new Czech COPD guideline reflects and covers these requirements.

Establishing a flow process to coumarin-8-carbaldehydes as important synthetic scaffolds.

Despite their usefulness as fluorophores and synthetic precursors, efficient and reliable routes to coumarin-8-carbaldehydes are lacking. We describe here a high-yielding continuous flow synthesis that requires no manual intermediate purification or work-up, giving access to multigram quantities of the aldehyde product.

The molecular basis for selective inhibition of unconventional mRNA splicing by an IRE1-binding small molecule.

IRE1 couples endoplasmic reticulum unfolded protein load to RNA cleavage events that culminate in the sequence-specific splicing of the Xbp1 mRNA and in the regulated degradation of diverse membrane-bound mRNAs. We report on the identification of a small molecule inhibitor that attains its selectivity by forming an unusually stable Schiff base with lysine 907 in the IRE1 endonuclease domain, explained by solvent inaccessibility of the imine bond in the enzyme-inhibitor complex. The inhibitor (abbreviated 4µ8C) blocks substrate access to the active site of IRE1 and selectively inactivates both Xbp1 splicing and IRE1-mediated mRNA degradation. Surprisingly, inhibition of IRE1 endonuclease activity does not sensitize cells to the consequences of acute endoplasmic reticulum stress, but rather interferes with the expansion of secretory capacity. Thus, the chemical reactivity and sterics of a unique residue in the endonuclease active site of IRE1 can be exploited by selective inhibitors to interfere with protein secretion in pathological settings.

Envenoming by the viperid snake Proatheris superciliaris: a case report.

Snake bites caused by viperid snakes of Atheris genus are extremely rare, envenoming of a bite of related viper Proatheris superciliaris was described only once in the literature. The present case study depicts the envenoming of a 57 years old Czech man, a private herpetologist, who was bitten to his finger. He developed painful local reaction, nausea, hematuria, hypertension, chest and lumbar pain. Coagulopathy and thrombocytopenia subsequently developed as well as acute renal failure, hepatic and lung lesion. Intensive care therapy was purely symptomatic and supportive as no antisera exists. Treatment included haemodialysis, substitution of fresh frozen plasma and platelets. Patient completely recovered during 1 month.