TNF-α and IFN-γ promote lymphocyte adhesion to endothelial junctional regions facilitating transendothelial migration

Mechanisms of HIV-mediated blood-brain barrier compromise and leukocyte transmigration under the current antiretroviral era

HIV-associated neurological compromise is observed in more than half of all people with HIV (PWH), even under antiretroviral therapy (ART). The mechanism has been associated with the early transmigration of HIV-infected monocytes across the BBB in a CCL2 and HIV replication-dependent manner. However, the mechanisms of chronic brain damage are unknown. We demonstrate that all PWH under ART have elevated circulating ATP levels that correlate with the onset of cognitive impairment even in the absence of a circulating virus. Serum ATP levels found in PWH with the most severe neurocognitive impairment trigger the transcellular migration of HIV-infected leukocytes across the BBB in a JAM-A and LFA-1-dependent manner. We propose that targeting transcellular leukocyte transmigration could reduce or prevent the devastating consequences of HIV within the brains of PWH under ART.

A Composite Biomarker Signature of Type 1 Diabetes Risk Identified via Augmentation of Parallel Multi-Omics Data from a Small Cohort

Background

Biomarkers of early pathogenesis of type 1 diabetes (T1D) are crucial to enable effective prevention measures in at-risk populations before significant damage occurs to their insulin producing beta-cell mass. We recently introduced the concept of integrated parallel multi-omics and employed a novel data augmentation approach which identified promising candidate biomarkers from a small cohort of high-risk T1D subjects. We now validate selected biomarkers to generate a potential composite signature of T1D risk.

Methods

Twelve candidate biomarkers, which were identified in the augmented data and selected based on their fold-change relative to healthy controls and cross-reference to proteomics data previously obtained in the expansive TEDDY and DAISY cohorts, were measured in the original samples by ELISA.

Results

All 12 biomarkers had established connections with lipid/lipoprotein metabolism, immune function, inflammation, and diabetes, but only 7 were found to be markedly changed in the high-risk subjects compared to the healthy controls: ApoC1 and PON1 were reduced while CETP, CD36, FGFR1, IGHM, PCSK9, SOD1, and VCAM1 were elevated.

Conclusions

Results further highlight the promise of our data augmentation approach in unmasking important patterns and pathologically significant features in parallel multi-omics datasets obtained from small sample cohorts to facilitate the identification of promising candidate T1D biomarkers for downstream validation. They also support the potential utility of a composite biomarker signature of T1D risk characterized by the changes in the above markers.

Protective effect of phosphorylated Athyrium multidentatum (Doll.) Ching polysaccharide on vascular endothelial cells in vitro and in vivo

The purpose of this study was to prepare phosphorylated Athyrium multidentatum (Doll.) Ching polysaccharide (PPS) and investigate its protective effect on vascular endothelial cells (VECs) in vitro and in vivo and the underlying mechanisms. Sodium tripolyphosphate (STPP) and sodium trimetaphosphate (STMP) were used as phosphorylation reagents and PPS was characterized by Fourier transform infrared (FT-IR), 13 C nuclear magnetic resonance (13 C NMR) and 31 P nuclear magnetic resonance (31 P NMR) spectra. Chemical analysis demonstrated that PPS was composed of mannose, glucosamine, rhamnose, glucuronic acid, galacturonic acid, galactosamine, glucose, galactose, xylose, arabinose, and fucose with a molar ratio of 11.36:0.42:4.03:1.12:1.81:0.26:33.25:24.12:6.85:14.46:2.32 and a molecular weight of 28,837 Da. Results from in vitro and in vivo assays revealed that PPS protected human umbilical vein endothelial cells (HUVECs) against H2 O2 -induced oxidative injury and attenuated D-galactose-induced VECs damage in mice. RNA sequencing (RNA-seq) analysis identified 18 differentially expressed genes (DEGs) between D-galactose-treated and PPS-pretreated mice abdominal aorta. A deep analysis of these DEGs disclosed that PPS regulated the expression of genes involved in the functions of vascular endothelium repairment, cell growth and proliferation, cell survival and apoptosis, inflammation, angiogenesis and antioxidant, indicating that these biological processes might play crucial roles in the protective actions of PPS on VECs.

Triple negative breast cancer metastasis is hindered by a peptide antagonist of F11R/JAM‑A protein

BACKGROUND

The F11R/JAM-A cell adhesion protein was examined as the therapeutic target in triple negative breast cancer (TNBC) with the use of the peptide antagonist to F11R/JAM-A, that previously inhibited the early stages of breast cancer metastasis in vitro.

METHODS

The online in silico analysis was performed by TNMPlot, UALCAN, and KM plotter. The in vitro experiments were performed to verify the effect of peptide 4D (P4D) on human endothelial cell lines EA.hy926 and HMEC-1 as well as on human TNBC cell line MDA-MB-231. The cell morphology upon P4D treatment was verified by light microscopy, while the cell functions were assessed by colony forming assay, MTT cell viability assay, BrdU cell proliferation assay, and Transepithelial/Endothelial Electrical Resistance measurements. The in vivo experiments on 4T1 murine breast cancer model were followed by histopathological analysis and a series of quantitative analyses of murine tissues.

RESULTS

By in silico analysis we have found the elevated gene expression in breast cancer with particular emphasis on TNBC. The elevated F11R expression in TNBC was related with poorer survival prognosis. Peptide 4D has altered the morphology and increased the permeability of endothelial monolayers. The colony formation, viability, and proliferation of MDA-MB-231 cells were decreased. P4D inhibited the metastasis in 4T1 breast cancer murine model in a statistically significant manner that was demonstrated by the resampling bootstrap technique.

CONCLUSIONS

The P4D peptide antagonist to F11R/JAM-A is able to hinder the metastasis in TNBC. This assumption needs to be confirmed by additional 4T1 mouse model study performed on larger group size, before making the decision on human clinical trials.

Cell-substratum and cell-cell adhesion forces and single-cell mechanical properties in mono- and multilayer assemblies from robotic fluidic force microscopy

The epithelium covers, protects, and actively regulates various formations and cavities of the human body. During embryonic development the assembly of the epithelium is crucial to the organoid formation, and the invasion of the epithelium is an essential step in cancer metastasis. Live cell mechanical properties and associated forces presumably play an important role in these biological processes. However, the direct measurement of cellular forces in a precise and high-throughput manner is still challenging. We studied the cellular adhesion maturation of epithelial Vero monolayers by measuring single-cell force-spectra with high-throughput fluidic force microscopy (robotic FluidFM). Vero cells were grown on gelatin-covered plates in different seeding concentrations, and cell detachment forces were recorded from the single-cell state, through clustered island formation, to their complete assembly into a sparse and then into a tight monolayer. A methodology was proposed to separate cell-substratum and cell-cell adhesion force and energy (work of adhesion) contributions based on the recorded force-distance curves. For comparison, cancerous HeLa cells were also measured in the same settings. During Vero monolayer formation, a significantly strengthening adhesive tendency was found, showing the development of cell-cell contacts. Interestingly, this type of step-by-step maturation was absent in HeLa cells. The attachment of cancerous HeLa cells to the assembled epithelial monolayers was also measured, proposing a new high-throughput method to investigate the biomechanics of cancer cell invasion. We found that HeLa cells adhere significantly stronger to the tight Vero monolayer than cells of the same origin. Moreover, the mechanical characteristics of Vero monolayers upon cancerous HeLa cell influence were recorded and analyzed. All these results provide insight into the qualitative assessment of cell-substratum and cell-cell mechanical contacts in mono- and multilayered assemblies and demonstrate the robustness and speed of the robotic FluidFM technology to reveal biomechanical properties of live cell assemblies with statistical significances.

Combinations of Toll-like receptor 8 agonist TL8-506 activate human tumor-derived dendritic cells

BACKGROUND

Dendritic cells (DCs) are professional antigen presenting cells that initiate immune defense to pathogens and tumor cells. Human tumors contain only few DCs that mostly display a non-activated phenotype. Hence, activation of tumor-associated DCs may improve efficacy of cancer immunotherapies. Toll-like receptor (TLR) agonists and interferons are known to promote DC maturation. However, it is unclear if DCs in human tumors respond to activation signals and which stimuli induce the optimal activation of human tumor DCs.

METHODS

We first screened combinations of TLR agonists, a STING agonist and interferons (IFNs) for their ability to activate human conventional DCs (cDCs). Two combinations: TL8-506 (a TLR8 agonist)+IFN-γ and TL8-506+Poly(I:C) (a TLR3 agonist) were studied in more detail. cDC1s and cDC2s derived from cord blood stem cells, blood or patient tumor samples were stimulated with either TL8-506+IFN-γ or TL8-506+Poly(I:C). Different activation markers were analyzed by ELISA, flow cytometry, NanoString nCounter Technology or single-cell RNA-sequencing. T cell activation and migration assays were performed to assess functional consequences of cDC activation.

RESULTS

We show that TL8-506 synergized with IFN-γ or Poly(I:C) to induce high expression of different chemokines and cytokines including interleukin (IL)-12p70 in human cord blood and blood cDC subsets in a combination-specific manner. Importantly, both combinations induced the activation of cDC subsets in patient tumor samples ex vivo. The expression of immunostimulatory genes important for anticancer responses including CD40, IFNB1, IFNL1, IL12A and IL12B were upregulated on stimulation. Furthermore, chemokines associated with CD8⁺ T cell recruitment were induced in tumor-derived cDCs in response to TL8-506 combinations. In vitro activation and migration assays confirmed that stimulated cDCs induce T cell activation and migration.

CONCLUSIONS

Our data suggest that cord blood-derived and blood-derived cDCs are a good surrogate to study treatment responses in human tumor cDCs. While most cDCs in human tumors display a non-activated phenotype, TL8-506 combinations drive human tumor cDCs towards an immunostimulatory phenotype associated with Th1 responses on stimulation. Hence, TL8-506-based combinations may be promising candidates to initiate or boost antitumor responses in patients with cancer.

Rac1 regulates lipid droplets formation, nanomechanical, and nanostructural changes induced by TNF in vascular endothelium in the isolated murine aorta

Endothelial inflammation is recognized as a critical condition in the development of cardiovascular diseases. TNF-induced inflammation of endothelial cells is linked to the formation of lipid droplets, augmented cortical stiffness, and nanostructural endothelial plasma membrane remodelling, but the insight into the mechanism linking these responses is missing. In the present work, we determined the formation of lipid droplets (LDs), nanomechanical, and nanostructural responses in the model of TNF-activated vascular inflammation in the isolated murine aorta using Raman spectroscopy, fluorescence imaging, atomic force microscopy (AFM), and scanning electron microscopy (SEM). We analysed the possible role of Rac1, a major regulator of cytoskeletal organization, in TNF-induced vascular inflammation. We demonstrated that the formation of LDs, polymerization of F-actin, alterations in cortical stiffness, and nanostructural protuberances in endothelial plasma membrane were mediated by the Rac1. In particular, we revealed a significant role for Rac1 in the regulation of the formation of highly unsaturated LDs formed in response to TNF. Inhibition of Rac1 also downregulated the overexpression of ICAM-1 induced by TNF, supporting the role of Rac1 in vascular inflammation. Altogether, our results demonstrate that LDs formation, an integral component of vascular inflammation, is activated by Rac1 that also regulates nanomechanical and nanostructural alterations linked to vascular inflammation.

The Role of Cytokines in Maintaining the Dynamics of Cell-Cell Interaction between Natural Killer Cells and Trophoblast Cells

We analyzed the effect of individual cytokines that are secretory products of placenta typical of the uteroplacental bed. The proinflammatory cytokines IL-6, IFNγ, and IL-1β increased the expression of TGFβR2 molecule by trophoblast cells, while VEGF and PLGF increased the expression of CD45, CD29, and CD54 adhesion molecule by trophoblast cells. The antiinflammatory cytokine IL-4 increased LeptinR expression by trophoblast cells. PMA and TNFα also enhanced the adhesion of NK cells to trophoblast cells. Our findings suggest that NK cells involved CD11a, CD11b, and CD18 molecules during their transmigration through trophoblast, as well as during their transendothelial migration.

The Roles of Junctional Adhesion Molecules (JAMs) in Cell Migration

The review briefly summarizes the role of the family of adhesion molecules, JAMs (junctional adhesion molecules), in various cell migration, covering germ cells, epithelial cells, endothelial cells, several leukocytes, and different cancer cells. These functions affect multiple diseases, including reproductive diseases, inflammation-related diseases, cardiovascular diseases, and cancers. JAMs bind to both similar and dissimilar proteins and take both similar and dissimilar effects on different cells. Concluding relevant results provides a reference to further research.

Pharmacogenomics of Anti-TNF Treatment Response Marks a New Era of Tailored Rheumatoid Arthritis Therapy

Rheumatoid arthritis (RA) is the most commonly occurring chronic inflammatory arthritis, the exact mechanism of which is not fully understood. Tumor Necrosis Factor (TNF)-targeting drugs has been shown to exert high effectiveness for RA, which indicates the key importance of this cytokine in this disease. Nevertheless, the response to TNF inhibitors varies, and approximately one third of RA patients are non-responders, which is explained by the influence of genetic factors. Knowledge in the field of pharmacogenomics of anti-TNF drugs is growing, but has not been applied in the clinical practice so far. Different genome-wide association studies identified a few single nucleotide polymorphisms associated with anti-TNF treatment response, which largely map genes involved in T cell function. Studies of the gene expression profile of RA patients have also indicated specific gene signatures that may be useful to develop novel prognostic tools. In this article, we discuss the significance of TNF in RA and present the current knowledge in pharmacogenomics related to anti-TNF treatment response.

Targeting interferon-γ in hyperinflammation: opportunities and challenges

Interferon-γ (IFNγ) is a pleiotropic cytokine with multiple effects on the inflammatory response and on innate and adaptive immunity. Overproduction of IFNγ underlies several, potentially fatal, hyperinflammatory or immune-mediated diseases. Several data from animal models and/or from translational research in patients point to a role of IFNγ in hyperinflammatory diseases, such as primary haemophagocytic lymphohistiocytosis, various forms of secondary haemophagocytic lymphohistiocytosis, including macrophage activation syndrome, and cytokine release syndrome, all of which are often managed by rheumatologists or in consultation with rheumatologists. Given the effects of IFNγ on B cells and T follicular helper cells, a role for IFNγ in systemic lupus erythematosus pathogenesis is emerging. To improve our understanding of the role of IFNγ in human disease, IFNγ-related biomarkers that are relevant for the management of hyperinflammatory diseases are progressively being identified and studied, especially because circulating levels of IFNγ do not always reflect its overproduction in tissue. These biomarkers include STAT1 (specifically the phosphorylated form), neopterin and the chemokine CXCL9. IFNγ-neutralizing agents have shown efficacy in the treatment of primary haemophagocytic lymphohistiocytosis in clinical trials and initial promising results have been obtained in various forms of secondary haemophagocytic lymphohistiocytosis, including macrophage activation syndrome. In clinical practice, there is a growing body of evidence supporting the usefulness of circulating CXCL9 levels as a biomarker reflecting IFNγ production.

CRISPR-Based Activation of Endogenous Expression of TPM1 Inhibits Inflammatory Response of Primary Human Coronary Artery Endothelial and Smooth Muscle Cells Induced by Recombinant Human Tumor Necrosis Factor α

Tumor necrosis factor α (TNFα) is one of the most important proinflammatory cytokines, which affects many processes associated with the growth and characteristics of endothelial, smooth muscle, and immune system cells. However, there is no correlation between most in vivo and in vitro studies on its role in endothelial cell proliferation and migration. In this study, we examined the effect of recombinant human (rh) TNFα produced in HEK293 cells on primary human coronary artery endothelial cells (pHCAECs) in the context of F-actin organization and such processes as migration and adhesion. Furthermore, we evaluated the possibility of the inhibition of the endothelial inflammatory response by the CRISPR-based regulation of TPM1 gene expression. We showed that TNFα-induced activation of pHCAECs was related to the reorganization of the actin cytoskeleton into parallel-arranged stress fibers running along the longer axis of pHCAECs. It allowed for the directed and parallel motion of the cells during coordinated migration. This change in F-actin organization promoted strong but discontinuous cell–cell contacts involved in signalization between migrating cells. Moreover, this form of intercellular connections together with locally increased adhesion was related to the formation of migrasomes and further migracytosis. Stabilization of the actin cytoskeleton through the CRISPR-based activation of endogenous expression of TPM1 resulted in the inhibition of the inflammatory response of pHCAECs following treatment with rh TNFα and stabilization of cell–cell junctions through reduced cleavage of vascular endothelial cadherin (VE-cadherin) and maintenance of the stable levels of α- and β-catenins. We also showed that CRISPR-based activation of TPM1 reduced inflammatory activation, proliferation, and migration of primary human coronary artery smooth muscle cells. Therefore, products of the TPM1 gene may be a potential therapeutic target for the treatment of proinflammatory vascular disorders.

The vascular niche in next generation microphysiological systems

In recent years, microphysiological system (MPS, also known as, organ-on-a-chip or tissue chip) platforms have emerged with great promise to improve the predictive capacity of preclinical modeling thereby reducing the high attrition rates when drugs move into trials. While their designs can vary quite significantly, in general MPS are bioengineered in vitro microenvironments that recapitulate key functional units of human organs, and that have broad applications in human physiology, pathophysiology, and clinical pharmacology. A critical next step in the evolution of MPS devices is the widespread incorporation of functional vasculature within tissues. The vasculature itself is a major organ that carries nutrients, immune cells, signaling molecules and therapeutics to all other organs. It also plays critical roles in inducing and maintaining tissue identity through expression of angiocrine factors, and in providing tissue-specific milieus (i.e., the vascular niche) that can support the survival and function of stem cells. Thus, organs are patterned, maintained and supported by the vasculature, which in turn receives signals that drive tissue specific gene expression. In this review, we will discuss published vascularized MPS platforms and present considerations for next-generation devices looking to incorporate this critical constituent. Finally, we will highlight the organ-patterning processes governed by the vasculature, and how the incorporation of a vascular niche within MPS platforms will establish a unique opportunity to study stem cell development.

Immune Responses in the Glaucomatous Retina: Regulation and Dynamics

Glaucoma is a multifactorial disease resulting in progressive vision loss due to retinal ganglion cell (RGC) dysfunction and death. Early events in the pathobiology of the disease include oxidative, metabolic, or mechanical stress that acts upon RGC, causing these to rapidly release danger signals, including extracellular ATP, resulting in micro- and macroglial activation and neuroinflammation. Danger signaling also leads to the formation of inflammasomes in the retina that enable maturation of proinflammatory cytokines such IL-1β and IL-18. Chronic neuroinflammation can have directly damaging effects on RGC, but it also creates a proinflammatory environment and compromises the immune privilege of the retina. In particular, continuous synthesis of proinflammatory mediators such as TNFα, IL-1β, and anaphylatoxins weakens the blood–retina barrier and recruits or activates T-cells. Recent data have demonstrated that adaptive immune responses strongly exacerbate RGC loss in animal models of the disease as T-cells appear to target heat shock proteins displayed on the surface of stressed RGC to cause their apoptotic death. It is possible that dysregulation of these immune responses contributes to the continued loss of RGC in some patients.

The involvement of TNF-α and TNF-β as proinflammatory cytokines in lymphocyte-mediated adaptive immunity of Nile tilapia by initiating apoptosis

Tumor necrosis factors (TNFs) are pleiotropic cytokines with important functions in homeostasis and disease pathogenesis. Recent advances have shown that TNFs are also involved in the regulation of adaptive immune responses. However, the knowledge about how TNF participates in and regulates adaptive immune response in early vertebrates is still limited. In present study, we identified two isoforms of TNF, TNF-α and TNF-β, from Nile tilapia Oreochromis niloticus (On-TNF-α and β). After analyzing the sequence characteristics, we investigated their regulatory roles in adaptive immune response of this fish species. On-TNF-α and β are evolutionarily conserved compare with their homologs from other vertebrates. Both TNFs were distributed in a wide range of tissues in O. niloticus, and with relative higher expression level in gill. After the animals were infected by Streptococcus agalactiae, mRNA levels of On-TNF-α and TNF-β in spleen lymphocytes were significantly upregulated during the primary response stage of adaptive immunity. Meanwhile, both TNF proteins in spleen lymphocytes were also dramatically elevated during the adaptive immune stage after bacterial infection. These results indicate the potential participation of On-TNF-α and TNF-β in adaptive immune response of Nile tilapia. Furthermore, On-TNF-α and β transcripts were obviously augmented, once spleen lymphocytes were activated by T cell-specific mitogen PHA. More importantly, both recombinant On-TNF-α and β could induce the apoptosis of head-kidney leukocytes of Nile tilapia. And On-TNF-β but not On-TNF-α promoted the apoptosis by activating caspase-8 in the target cells. Altogether, our study revealed that TNF-α and TNF-β participated in the lymphocyte-mediated adaptive immune response of Nile tilapia by initiating the apoptosis, and thus shed novel perspective for the regulatory mechanism of adaptive immunity in teleost.

Nano-scientific Application of Atomic Force Microscopy in Pathology: from Molecules to Tissues

The advantages of atomic force microscopy (AFM) in biological research are its high imaging resolution, sensitivity, and ability to operate in physiological conditions. Over the past decades, rigorous studies have been performed to determine the potential applications of AFM techniques in disease diagnosis and prognosis. Many pathological conditions are accompanied by alterations in the morphology, adhesion properties, mechanical compliances, and molecular composition of cells and tissues. The accurate determination of such alterations can be utilized as a diagnostic and prognostic marker. Alteration in cell morphology represents changes in cell structure and membrane proteins induced by pathologic progression of diseases. Mechanical compliances are also modulated by the active rearrangements of cytoskeleton or extracellular matrix triggered by disease pathogenesis. In addition, adhesion is a critical step in the progression of many diseases including infectious and neurodegenerative diseases. Recent advances in AFM techniques have demonstrated their ability to obtain molecular composition as well as topographic information. The quantitative characterization of molecular alteration in biological specimens in terms of disease progression provides a new avenue to understand the underlying mechanisms of disease onset and progression. In this review, we have highlighted the application of diverse AFM techniques in pathological investigations.

Functional inhibition of F11 receptor (F11R/junctional adhesion molecule-A/JAM-A) activity by a F11R-derived peptide in breast cancer and its microenvironment

Purpose

To examine the involvement of the F11R/JAM-A protein in breast cancer metastasis, we utilized the F11R/JAM-A antagonistic peptide 4D (P4D) in experiments of transendothelial migration (TEM) of breast cancer cells.

Methods

Experiments were conducted in the mouse 4T1 breast cancer model utilizing the human mammary epithelial cell and endothelial cell lines. The levels of soluble F11R/JAM-A (sJAM-A) in the murine plasmas were measured by ELISA. Levels of F11R/JAM-A mRNA and protein in cell lines were assessed by qRT-PCR and Western blot, respectively. Cell surface expression of F11R/JAM-A was demonstrated by flow cytometry. Functional tests included the TEM of breast cancer cells and adhesion of breast cancer cells to the endothelium. The endothelial permeability was studied by fluorescent tracer assay and by the Real-Time Cell Analysis (RTCA).

Results

The tumor inducers Tβ4 and TGF-β1 reduced the levels of sJAM-A in murine plasma, and reduced the F11R/JAM-A protein levels in the human microvascular endothelial cell line HMEC-1. The adhesion and TEM measured between breast cancer cells and inflamed or Tβ4-treated endothelium were inhibited by P4D. The presence of P4D did not destabilize the pre-existing tight junctions in the endothelial monolayer. The barrier-protecting effect of P4D was stronger than that of forskolin, when a booster dose of P4D was applied to the inflamed endothelium.

Conclusions

F11R/JAM-A protein can be considered as a novel target in the treatment of breast cancer metastasis. In vivo and clinical studies are needed to further investigate the effectiveness of F11R/JAM-A-derived peptide as a possible anti-metastatic drug.

Electronic supplementary material

The online version of this article (10.1007/s10549-019-05471-x) contains supplementary material, which is available to authorized users.

A gain of function paradox: Targeted therapy for glioblastoma associated with abnormal NHE9 expression

Glioblastoma (GBM) is the most frequent and inevitably lethal primary brain cancer in adults. It is recognized that the overexpression of the endosomal Na⁺ /H⁺ exchanger NHE9 is a potent driver of GBM progression. Patients with NHE9 overexpression have a threefold lower median survival relative to GBM patients with normal NHE9 expression, using available treatment options. New treatment strategies tailored for this GBM subset are much needed. According to the prevailing model, NHE9 overexpression leads to an increase in plasma membrane density of epidermal growth factor receptors (EGFRs) which consequently enhances GBM cell proliferation and migration. However, this increase is not specific to EGFRs. In fact, the hallmark of NHE9 overexpression is a pan-specific increase in plasma membrane receptors. Paradoxically, we report that this gain of function in NHE9 can be exploited to effectively target GBM cells for destruction. When exposed to gold nanoparticles, NHE9 overexpressing GBM cells accumulated drastically high amounts of gold via receptor-mediated endocytosis, relative to control. Irradiation of these cells with near-infrared light led to apoptotic tumour cell death. A major limitation for delivering therapeutics to GBM cells is the blood-brain barrier (BBB). Here, we demonstrate that macrophages loaded with gold nanoparticles can cross the BBB, deliver the gold nanoparticles and effect the demise of GBM cells. In combination with receptor tyrosine kinase inhibition, we show this approach holds great promise for a new GBM-targeted therapy.

Glioblastoma adhesion in a quick-fit hybrid microdevice

Translational research requires reliable biomedical microdevices (BMMD) to mimic physiological conditions and answer biological questions. In this work, we introduce a reversibly sealed quick-fit hybrid BMMD that is operator-friendly and bubble-free, requires low reagent and cell consumption, enables robust and high throughput performance for biomedical experiments. Specifically, we fabricate a quick-fit poly(methyl methacrylate) and poly(dimethyl siloxane) (PMMA/PDMS) prototype to illustrate its utilities by probing the adhesion of glioblastoma cells (T98G and U251MG) to primary endothelial cells. In static condition, we confirm that angiopoietin-Tie2 signaling increases the adhesion of glioblastoma cells to endothelial cells. Next, to mimic the physiological hemodynamic flow and investigate the effect of physiological electric field, the endothelial cells are pre-conditioned with concurrent shear flow (with fixed 1 Pa shear stress) and direct current electric field (dcEF) in the quick-fit PMMA/PDMS BMMD. With shear flow alone, endothelial cells exhibit classical parallel alignment; while under a concurrent dcEF, the cells align perpendicularly to the electric current when the dcEF is greater than 154 V m^− 1. Moreover, with fixed shear stress of 1 Pa, T98G glioblastoma cells demonstrate increased adhesion to endothelial cells conditioned in dcEF of 154 V m^− 1, while U251MG glioblastoma cells show no difference. The quick-fit hybrid BMMD provides a simple and flexible platform to create multiplex systems, making it possible to investigate complicated biological conditions for translational research.

Primary M1 macrophages as multifunctional carrier combined with PLGA nanoparticle delivering anticancer drug for efficient glioma therapy

Glioma remains difficult to treat because of the infiltrative growth of tumor cells and their resistance to standard therapy. Despite rapid development of targeted drug delivery system, the current therapeutic efficacy is still challenging. Based on our previous studies, macrophages have been proved to be promising drug carrier for active glioma delivery. To make full use of macrophage carrier, primary M1 macrophages were proposed to replace regular macrophage to deliver nanodrugs into glioma, because M1 macrophages not only have the natural ability to home into tumor tissues, but they also have stronger phagocytic capability than other types of macrophage, which can enable them to uptake enough drug-loaded nanoparticles for therapy. In addition, M1 macrophages are not easily affected by harsh tumor microenvironment and inhibit tumor growth themselves. In this study, M1 macrophage-loaded nanoparticles (M1-NPs) were prepared by incubating poly(lactide-co-glycolide) (PLGA) nanoparticles with primary M1 macrophages. In vitro cell assays demonstrated M1 macrophage still maintained good tumor tropism capability after particle loading, and could efficiently carry particles across endothelial barrier into tumor tissues. In vivo imaging verified that M1-NPs exhibited higher brain tumor distribution than free nanoparticles. DOX@M1-NPs (doxorubicin-loaded M1-NPs) presented significantly enhanced anti-glioma effect with prolonged survival median and increased cell apoptosis. In conclusion, the results provided a new strategy exploiting M1 macrophage as carrier for drug delivery, which improved targeting efficiency and therapeutic efficacy of chemodrugs for glioma therapy.

Modulation of T-cell responses by anti-tumor necrosis factor treatments in rheumatoid arthritis: a review

Tumor necrosis factor (TNF) is a pleiotropic cytokine involved in many aspects of immune regulation. Anti-TNF biological therapy has been considered a breakthrough in the treatment of chronic autoimmune diseases, such as rheumatoid arthritis (RA). In this review, because of the major involvement of T cells in RA pathogenesis, we discuss the effects of anti-TNF biotherapy on T-cell responses in RA patients. We also outline the potential fields for future research in the area of anti-TNF therapy in RA.This could be useful to better understand the therapeutic efficiency and the side effects that are encountered in RA patients. Better targeting of T cells in RA could help set more specific anti-TNF strategies and develop prediction tools for response.

Junctional adhesion molecules mediate transendothelial migration of dendritic cell vaccine in cancer immunotherapy

In vitro generated dendritic cells (DCs) have been studied in cancer immunotherapy for decades. However, the detailed molecular mechanism underlying transendothelial migration (TEM) of DC vaccine across the endothelial barrier to regional lymph nodes (LNs) remains largely unknown. Here, we found that junctional adhesion molecule (JAM)-Like (JAML) is involved in the TEM of mouse bone marrow-derived DCs (BMDCs). Treatment with an anti-JAML antibody or JAML knock-down significantly reduced the TEM activity of BMDCs, leading to impairment of DC-based cancer immunotherapy. We found that the interaction of JAML of BMDCs with the coxsackie and adenovirus receptor of endothelial cells plays a crucial role in the TEM of BMDCs. On the other hand, human monocyte-derived DCs (MoDCs) did not express the JAML protein but still showed normal TEM activity. We found that MoDCs express only JAM1 and that the homophilic interaction of JAM1 is essential for MoDC TEM across a HUVEC monolayer. Our findings suggest that specific JAM family members play an important role in the TEM of in vitro-generated mouse and human DCs from the inoculation site to regional LNs in DC-based cancer immunotherapy.

T cell acute lymphoblastic leukemia (T-ALL): New insights into the cellular origins and infiltration mechanisms common and unique among hematologic malignancies

T-cell acute lymphoblastic leukemia (T-ALL) accounts for 15% and 25% of total childhood and adult ALL cases, respectively. During T-ALL, patients are at risk of organ infiltration by leukemic T-cells. Infiltration is a major consequence of disease relapse and correlates with poor prognosis. Transendothelial migration of leukemic cells is required to exit the blood stream into target organs. While mechanisms of normal T-cell transmigration are well known, the mechanisms of leukemic T-cell extravasation remain elusive; but involvement of chemokines, integrins and Notch signaling play critical roles. Here, we summarize current knowledge about molecular mechanisms of leukemic T-cell infiltration with special emphasis on the newly identified subtype early T-cell-progenitor (ETP)-ALL. Furthermore, we compare the extravasation potential of T-ALL cells with that of other hematologic malignancies such as B-ALL and acute myeloid leukemia (AML).

Cortistatin reduces atherosclerosis in hyperlipidemic ApoE-deficient mice and the formation of foam cells

Atherosclerosis is a chronic inflammatory cardiovascular disease that is responsible of high mortality worldwide. Evidence indicates that maladaptive autoimmune responses in the arterial wall play critical roles in the process of atherosclerosis. Cortistatin is a neuropeptide expressed in the vascular system and atherosclerotic plaques that regulates vascular calcification and neointimal formation, and inhibits inflammation in different experimental models of autoimmune diseases. Its role in inflammatory cardiovascular disorders is largely unexplored. The aim of this study is to investigate the potential therapeutic effects of cortistatin in two well-established preclinical models of atherosclerosis, and the molecular and cellular mechanisms involved. Systemic treatment with cortistatin reduced the number and size of atherosclerotic plaques in carotid artery, heart, aortic arch and aorta in acute and chronic atherosclerosis induced in apolipoprotein E-deficient mice fed a high-lipid diet. This effect was exerted at multiple levels. Cortistatin reduced Th1/Th17-driven inflammatory responses and increased regulatory T cells in atherosclerotic arteries and lymphoid organs. Moreover, cortistatin reduced the capacity of endothelial cells to bind and recruit immune cells to the plaque and impaired the formation of foam cells by enhancing cholesterol efflux from macrophages. Cortistatin emerges as a new candidate for the treatment of the clinical manifestations of atherosclerosis.

Reinforcement of integrin-mediated T-Lymphocyte adhesion by TNF-induced Inside-out Signaling

Integrin-mediated leukocyte adhesion to endothelial cells is a crucial step in immunity against pathogens. Whereas the outside-in signaling pathway in response to the pro-inflammatory cytokine tumour necrosis factor (TNF) has already been studied in detail, little knowledge exists about a supposed TNF-mediated inside-out signaling pathway. In contrast to the outside-in signaling pathway, which relies on the TNF-induced upregulation of surface molecules on endothelium, inside-out signaling should also be present in an endothelium-free environment. Using single-cell force spectroscopy, we show here that stimulating Jurkat cells with TNF significantly reinforces their adhesion to fibronectin in a biomimetic in vitro assay for cell-surface contact times of about 1.5 seconds, whereas for larger contact times the effect disappears. Analysis of single-molecule ruptures further demonstrates that TNF strengthens sub-cellular single rupture events at short cell-surface contact times. Hence, our results provide quantitative evidence for the significant impact of TNF-induced inside-out signaling in the T-lymphocyte initial adhesion machinery.

Recombinant IL-7/HGFβ hybrid cytokine separates acute graft-versus-host-disease from graft-versus-tumour activity by altering donor T cell trafficking

Given that donor T cells from a transplant contribute both the desired graft-versus-tumour (GVT) effect and detrimental graft-versus-host disease (GVHD), strategies to separate GVHD and GVT activity are a major clinical goal. We have previously demonstrated that in vivo administration of a recombinant (r)IL-7/HGFβ hybrid cytokine, consisting of interleukin-7 (IL-7, IL7) and the β-chain of hepatocyte growth factor (HGFβ), significantly inhibits the growth of cancer cells in murine tumour models. The antit-umour effect of rIL-7/HGFβ is related to a marked infiltration T cells in the tumour tissues. We have also shown that GVHD was not induced in rIL-7/HGFβ-treated T cell-depleted allogeneic haematopoietic stem cell transplantation (HSCT) recipients. We show here that, in T cell-replete allogeneic HSCT murine models, rIL-7/HGFβ attenuated acute GVHD (aGVHD), while promoting GVT activity. This was related to an alteration of donor T cell trafficking, with an increased infiltration of donor T cells into tumour tissues and the lympho-haematopoietic system but decreased number of the T cells in the GVHD target organs. Therefore, rIL-7/HGFβ may offer a new tool to alleviate aGVHD while prompting GVT, and to study the molecular regulation of T cell trafficking.

Nanomechanics of Cells and Biomaterials Studied by Atomic Force Microscopy

The behavior and mechanical properties of cells are strongly dependent on the biochemical and biomechanical properties of their microenvironment. Thus, understanding the mechanical properties of cells, extracellular matrices, and biomaterials is key to understanding cell function and to develop new materials with tailored mechanical properties for tissue engineering and regenerative medicine applications. Atomic force microscopy (AFM) has emerged as an indispensable technique for measuring the mechanical properties of biomaterials and cells with high spatial resolution and force sensitivity within physiologically relevant environments and timescales in the kPa to GPa elastic modulus range. The growing interest in this field of bionanomechanics has been accompanied by an expanding array of models to describe the complexity of indentation of hierarchical biological samples. Furthermore, the integration of AFM with optical microscopy techniques has further opened the door to a wide range of mechanotransduction studies. In recent years, new multidimensional and multiharmonic AFM approaches for mapping mechanical properties have been developed, which allow the rapid determination of, for example, cell elasticity. This Progress Report provides an introduction and practical guide to making AFM-based nanomechanical measurements of cells and surfaces for tissue engineering applications.

CHRONOS: a time-varying method for microRNA-mediated subpathway enrichment analysis

MOTIVATION

In the era of network medicine and the rapid growth of paired time series mRNA/microRNA expression experiments, there is an urgent need for pathway enrichment analysis methods able to capture the time- and condition-specific 'active parts' of the biological circuitry as well as the microRNA impact. Current methods ignore the multiple dynamical 'themes'-in the form of enriched biologically relevant microRNA-mediated subpathways-that determine the functionality of signaling networks across time.

RESULTS

To address these challenges, we developed time-vaRying enriCHment integrOmics Subpathway aNalysis tOol (CHRONOS) by integrating time series mRNA/microRNA expression data with KEGG pathway maps and microRNA-target interactions. Specifically, microRNA-mediated subpathway topologies are extracted and evaluated based on the temporal transition and the fold change activity of the linked genes/microRNAs. Further, we provide measures that capture the structural and functional features of subpathways in relation to the complete organism pathway atlas. Our application to synthetic and real data shows that CHRONOS outperforms current subpathway-based methods into unraveling the inherent dynamic properties of pathways.

AVAILABILITY AND IMPLEMENTATION

CHRONOS is freely available at http://biosignal.med.upatras.gr/chronos/

CONTACT

tassos.bezerianos@nus.edu.sg

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Interferon Gamma Counteracts the Angiogenic Switch and Induces Vascular Permeability in Dextran Sulfate Sodium Colitis in Mice

BACKGROUND

Interferon (IFN)-γ is a central pathogenesis factor in inflammatory bowel disease (IBD) with pleiotropic effects on many different cell types. However, as yet, the immune modulatory functions of IFN-γ in IBD have been predominantly investigated. Based on previous studies showing that IFN-γ acts antiangiogenic in colorectal carcinoma, we investigated the effects of IFN-γ on the vascular system in IBD.

METHODS

Colon tissues of patients with IBD and dextran sulfate sodium-induced colitis in mice were subjected to immunohistochemistry, quantitative real-time polymerase chain reactions, and in situ hybridization to quantify cell activation, angiogenesis, and immune responses. Vascular structure and permeability in mice were analyzed by ultramicroscopy and in vivo confocal laser endomicroscopy.

RESULTS

We showed a significantly increased blood vessel density in IBD and dextran sulfate sodium colitis. In mice, this was associated with a disorganized blood vessel structure and profound vascular leakage. As compared with genes associated with angiogenesis, genes associated with inflammatory cell activation including IFN-γ were more strongly upregulated in colitis tissues. IFN-γ exerted direct effects on endothelial cells in IBD tissues in vivo, as indicated by the expression of IFN-γ-induced guanylate binding protein 1 (GBP-1). Neutralization of IFN-γ in the acute dextran sulfate sodium colitis model demonstrated that this cytokine exerts endogenous angiostatic activity in IBD and contributes to increased vascular permeability.

CONCLUSIONS

The dissection of the pleiotropic activities of IFN-γ in IBD provides new insights to the pathological functions of this cytokine and may be of high relevance for the optimization of combination therapy approaches.

HGAL localization to cell membrane regulates B-cell receptor signaling

Human germinal center-associated lymphoma (HGAL) is specifically expressed only in germinal center (GC) B lymphocytes and GC-derived lymphomas. HGAL protein decreases lymphocyte motility by inhibiting the ability of myosin to translocate actin via direct interaction with F-actin and myosin II and by activating RhoA signaling via direct interactions with RhoA-specific guanine nucleotide exchange factors. HGAL protein also regulates B-cell receptor (BCR) signaling by directly binding to and enhancing Syk kinase activity and activation of its downstream effectors. Herein we demonstrate that HGAL protein can be myristoylated and palmitoylated and that these modifications localize HGAL to cellular membrane raft microdomains with distinct consequences for BCR signaling and chemoattractant-induced cell mobility. In BCR signaling, raft localization of HGAL facilitates interaction with Syk and modulation of the BCR activation and signaling, which induces HGAL phosphorylation and redistribution from lipid raft to bulk membrane and cytoplasm, followed by degradation. In contrast, HGAL myristoylation and palmitoylation avert its inhibitory effects on chemoattractant-induced cell motility. These findings further elucidate the growing and complex role of HGAL in B-cell biology and suggest that membrane-bound and cytoplasmic HGAL protein differently regulates distinct biological processes.

Platelets and their chemokines in atherosclerosis-clinical applications

The concept of platelets as important players in the process of atherogenesis has become increasingly accepted due to accumulating experimental and clinical evidence. Despite the progress in understanding the molecular details of atherosclerosis, particularly by using animal models, the inflammatory and thrombotic roles of activated platelet s especially in the human system remain difficult to dissect, as often only the complications of atherosclerosis, i.e., stroke and myocardial infarction are definable but not the plaque burden. Platelet indices including platelet count and mean platelet volume (MPV) and soluble mediators released by activated platelets are associated with atherosclerosis. The chemokine CXCL4 has multiple atherogenic activities, e.g., altering the differentiation of T cells and macrophages by inhibiting neutrophil and monocyte apoptosis and by increasing the uptake of oxLDL and synergizing with CCL5. CCL5 is released and deposited on endothelium by activated platelets thereby triggering atherogenic monocyte recruitment, which can be attenuated by blocking the corresponding chemokine receptor CCR5. Atheroprotective and plaque stabilizing properties are attributed to CXCL12, which plays an important role in regenerative processes by attracting progenitor cells. Its release from luminal attached platelets accelerates endothelial healing after injury. Platelet surface molecules GPIIb/IIIa, GP1bα, P-selectin, JAM-A and the CD40/CD40L dyade are crucially involved in the interaction with endothelial cells, leukocytes and matrix molecules affecting atherogenesis. Beyond the effects on the arterial inflammatory infiltrate, platelets affect cholesterol metabolism by binding, modifying and endocytosing LDL particles via their scavenger receptors and contribute to the formation of lipid laden macrophages. Current medical therapies for the prevention of atherosclerotic therapies enable the elucidation of mechanisms linking platelets to inflammation and atherosclerosis.

Atherogenic mononuclear cell recruitment is facilitated by oxidized lipoprotein-induced endothelial junctional adhesion molecule-A redistribution

BACKGROUND

Junctional adhesion molecule (JAM-) A is a transmembrane protein expressed in many cell types and maintains junctional integrity in endothelial cells. Upon inflammatory stimulation, JAM-A relocates to the apical surface and might thereby facilitate the recruitment of leukocytes.

OBJECTIVE

Although inflammatory JAM-A redistribution is an established process, further effort is required to understand its exact role in the transmigration of mononuclear cells, particularly under atherogenic conditions.

METHODS

By the use of RNA interference and genetic deletion, the role of JAM-A in the transmigration of T cells and monocytes through aortic endothelial cells was investigated. JAM-A-localization and subsequent mononuclear cell rolling, adhesion and transmigration were explored during endothelial inflammation, induced by oxidized LDL or cytokines.

RESULTS

RNA interference or genetic deletion of JAM-A in aortic endothelial cells resulted in a decreased transmigration of mononuclear cells. Treatment of the endothelial cells with oxLDL resulted in an increase of both permeability and apical JAM-A presentation, as shown by bead adhesion and confocal microscopy experiments. Redistribution of JAM-A resulted in an increased leukocyte adhesion and transmigration, which could be inhibited with antibodies against JAM-A or by lovastatin-treatment, but not with the peroxisome proliferator activated receptor gamma-agonist pioglitazone.

CONCLUSIONS

This study demonstrates that redistribution of JAM-A in endothelial cells after stimulation with pro-atherogenic oxidized lipoproteins results in increased transmigration of mononuclear cells. This inflammatory dispersal of JAM-A could be counteracted with statins, revealing a novel aspect of their mechanism of action.