Differential targeting of immune-cells by Pixantrone in experimental myasthenia gravis

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Innate immunity in myasthenia gravis thymus: Pathogenic effects of Toll-like receptor 4 signaling on autoimmunity

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TCTN2:a novel tumor marker with oncogenic properties

Tectonic family member 2 (TCTN2) encodes a transmembrane protein that belongs to the tectonic family, which is involved in ciliary functions. Previous studies have demonstrated the role of tectonics in regulating a variety of signaling pathways at the transition zone of cilia. However, the role of tectonics in cancer is still unclear. Here we identify that TCTN2 is overexpressed in colorectal, lung and ovary cancers. We show that different cancer cell lines express the protein that localizes at the plasma membrane, facing the intracellular milieu. TCTN2 over-expression in cancer cells resulted in an increased ability to form colonies in an anchorage independent way. On the other hand, downregulation of TCTN2 using targeted epigenetic editing in cancer cells significantly reduced colony formation, cell invasiveness, increased apoptosis and impaired assembly of primary cilia. Taken together, our results indicate that TCTN2 acts as an oncogene, making it an interesting cancer-associated protein and a potential candidate for therapeutic applications.</p

Nicotinic acid adenine dinucleotide phosphate-mediated calcium signalling in effector T cells regulates autoimmunity of the central nervous system

Nicotinic acid adenine dinucleotide phosphate represents a newly identified second messenger in T cells involved in antigen receptor-mediated calcium signalling. Its function in vivo is, however, unknown due to the lack of biocompatible inhibitors. Using a recently developed inhibitor, we explored the role of nicotinic acid adenine dinucleotide phosphate in autoreactive effector T cells during experimental autoimmune encephalomyelitis, the animal model for multiple sclerosis. We provide in vitro and in vivo evidence that calcium signalling controlled by nicotinic acid adenine dinucleotide phosphate is relevant for the pathogenic potential of autoimmune effector T cells. Live two photon imaging and molecular analyses revealed that nicotinic acid adenine dinucleotide phosphate signalling regulates T cell motility and re-activation upon arrival in the nervous tissues. Treatment with the nicotinic acid adenine dinucleotide phosphate inhibitor significantly reduced both the number of stable arrests of effector T cells and their invasive capacity. The levels of pro-inflammatory cytokines interferon-gamma and interleukin-17 were strongly diminished. Consecutively, the clinical symptoms of experimental autoimmune encephalomyelitis were ameliorated. In vitro, antigen-triggered T cell proliferation and cytokine production were evenly suppressed. These inhibitory effects were reversible: after wash-out of the nicotinic acid adenine dinucleotide phosphate antagonist, the effector T cells fully regained their functions. The nicotinic acid derivative BZ194 induced this transient state of non-responsiveness specifically in post-activated effector T cells. Naïve and long-lived memory T cells, which express lower levels of the putative nicotinic acid adenine dinucleotide phosphate receptor, type 1 ryanodine receptor, were not targeted. T cell priming and recall responses in vivo were not reduced. These data indicate that the nicotinic acid adenine dinucleotide phosphate/calcium signalling pathway is essential for the recruitment and the activation of autoaggressive effector T cells within their target organ. Interference with this signalling pathway suppresses the formation of autoimmune inflammatory lesions and thus might qualify as a novel strategy for the treatment of T cell mediated autoimmune diseases

Tollip Is a Mediator of Protein Sumoylation

Tollip is an interactor of the interleukin-1 receptor involved in its activation. The endosomal turnover of ubiquitylated IL-1RI is also controlled by Tollip. Furthermore, together with Tom1, Tollip has a general role in endosomal protein traffic. This work shows that Tollip is involved in the sumoylation process. Using the yeast two-hybrid technique, we have isolated new Tollip partners including two sumoylation enzymes, SUMO-1 and the transcriptional repressor Daxx. The interactions were confirmed by GST-pull down experiments and immunoprecipitation of the co-expressed recombinants. More specifically, we show that the TIR domain of the cytoplasmic region of IL-1RI is a sumoylation target of Tollip. The sumoylated and unsumoylated RanGAP-1 protein also interacts with Tollip, suggesting a possible role in RanGAP-1 modification and nuclear-cytoplasmic protein translocation. In fact, Tollip is found in the nuclear bodies of SAOS-2/IL-1RI cells where it colocalizes with SUMO-1 and the Daxx repressor. We conclude that Tollip is involved in the control of both nuclear and cytoplasmic protein traffic, through two different and often contrasting processes: ubiquitylation and sumoylation

Differential targeting of immune-cells by Pixantrone in experimental myasthenia gravis

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Development of a Specific Monoclonal Antibody to Detect Male Cells Expressing the RPS4Y1 Protein

Hemophilia is an X-linked recessive bleeding disorder. In pregnant women carrier of hemophilia, the fetal sex can be determined by non-invasive analysis of fetal DNA circulating in the maternal blood. However, in case of a male fetus, conventional invasive procedures are required for the diagnosis of hemophilia. Fetal cells, circulating in the maternal bloodstream, are an ideal target for a safe non-invasive prenatal diagnosis. Nevertheless, the small number of cells and the lack of specific fetal markers have been the most limiting factors for their isolation. We aimed to develop monoclonal antibodies (mAbs) against the ribosomal protein RPS4Y1 expressed in male cells. By Western blotting, immunoprecipitation and immunofluorescence analyses performed on cell lysates from male human hepatoma (HepG2) and female human embryonic kidney (HEK293) we developed and characterized a specific monoclonal antibody against the native form of the male RPS4Y1 protein that can distinguish male from female cells. The availability of the RPS4Y1-targeting monoclonal antibody should facilitate the development of novel methods for the reliable isolation of male fetal cells from the maternal blood and their future use for non-invasive prenatal diagnosis of X-linked inherited disease such as hemophilia

Unusual Association of NF-κB Components in Tumor-Associated Macrophages (TAMs) Promotes HSPG2-Mediated Immune-Escaping Mechanism in Breast Cancer

The cellular heterogeneity of the tumor environment of breast cancer (BC) is extremely complex and includes different actors such as neoplastic, stromal, and immunosuppressive cells, which contribute to the chemical and mechanical modification of the environment surrounding the tumor-exasperating immune-escaping mechanisms. In addition to molecular signals that make the tumor microenvironment (TME) unacceptable for the penetrance of the immune system, the physical properties of tumoral extracellular matrix (tECM) also have carved out a fundamental role in the processes of the protection of the tumor niche. Tumor-associated macrophages (TAMs), with an M2 immunosuppressive phenotype, are important determinants for the establishment of a tumor phenotype excluded from T cells. NF-κB transcription factors orchestrate innate immunity and represent the common thread between inflammation and cancer. Many studies have focused on canonical activation of NF-κB; however, activation of non-canonical signaling predicts poor survival and resistance to therapy. In this scenario, we demonstrated the existence of an unusual association of NF-κB components in TAMs that determines the deposition of HSPG2 that affects the stiffness of tECM. These results highlight a new mechanism counterbalanced between physical factors and a new perspective of mechano-pathology to be targeted to counteract immune evasion in BC

Reconstitution of the Human Nigro-striatal Pathway on-a-Chip Reveals OPA1-Dependent Mitochondrial Defects and Loss of Dopaminergic Synapses

Stem cell-derived neurons are generally obtained in mass cultures that lack both spatial organization and any meaningful connectivity. We implement a microfluidic system for long-term culture of human neurons with patterned projections and synaptic ter- minals. Co-culture of human midbrain dopaminergic and striatal medium spiny neurons on the microchip establishes an orchestrated nigro-striatal circuitry with functional dopaminergic synapses. We use this platform to dissect the mitochondrial dysfunc- tions associated with a genetic form of Parkinson’s disease (PD) with OPA1 mutations. Remarkably, we find that axons of OPA1 mutant dopaminergic neu- rons exhibit a significant reduction of mitochondrial mass. This defect causes a significant loss of dopa- minergic synapses, which worsens in long-term cultures. Therefore, PD-associated depletion of mitochondria at synapses might precede loss of neuronal connectivity and neurodegeneration. In vitro reconstitution of human circuitries by micro- fluidic technology offers a powerful system to study brain networks by establishing ordered neuronal compartments and correct synapse identity