Plexin-A4 is a receptor for sema6A and sema6B and associates with neuropilins to transduce signals of class-3 semaphorins. We observed that plexin-A1 and plexin-A4 are required simultaneously for ...transduction of inhibitory sema3A signals and that they form complexes. Unexpectedly, inhibition of plexin-A1 or plexin-A4 expression in endothelial cells using specific shRNAs resulted in prominent plexin type specific rearrangements of the actin cytoskeleton that were accompanied by inhibition of bFGF and VEGF-induced cell proliferation. The two responses were not interdependent since silencing plexin-A4 in U87MG glioblastoma cells inhibited cell proliferation and strongly inhibited the formation of tumors from these cells without affecting cytoskeletal organization. Plexin-A4 formed stable complexes with the FGFR1 and VEGFR-2 tyrosine-kinase receptors and enhanced VEGF-induced VEGFR-2 phosphorylation in endothelial cells as well as bFGF-induced cell proliferation. We also obtained evidence suggesting that some of the pro-proliferative effects of plexin-A4 are due to transduction of autocrine sema6B-induced pro-proliferative signals, since silencing sema6B expression in endothelial cells and in U87MG cells mimicked the effects of plexin-A4 silencing and also inhibited tumor formation from the U87MG cells. Our results suggest that plexin-A4 may represent a target for the development of novel anti-angiogenic and anti-tumorigenic drugs.
The STIL protein is essential for centriole replication and for the non-templated, de novo centriole biogenesis that is required for mammalian embryogenesis. Here we performed quantitative ...biophysical and structural analysis of the central short coiled coil domain (CCD) of STIL that is critical for its function. Using biophysical, biochemical and cell biology approaches, we identified the specific residues in the CCD that mediate the oligomerization, centrosomal localization and protein interactions of STIL. We characterized the structural properties of the coiled coil peptide using circular dichroism spectroscopy and size exclusion chromatography. We identified two regions in this domain, containing eight hydrophobic residues, which mediate the coiled coil oligomerization. Mutations in these residues destabilized the coiled coil thermodynamically but in most cases did not affect its secondary structure. Reconstituting mouse embryonic fibroblasts lacking endogenous Stil, we show that STIL oligomerization mediated by these residues is not only important for the centrosomal functions of STIL during the canonical duplication process but also for de-novo formation of centrosomes.
Fibrodysplasia ossificans progressiva (FOP) is the most catastrophic form of heterotopic ossification, due to ongoing intracellular signaling through the bone morphogenic protein pathway. The ...paroxysmal appearance of inflammatory lumps and elevated inflammatory markers during flares, suggest that FOP is an auto-inflammatory disease. Based on evidence, demonstrating a role for interleukin-1β (IL-1β) in other forms of heterotopic ossification, we hypothesized that treating FOP patients with anti-IL-1 agents could help lower the rate of FOP paroxysms and/or limit the symptoms and residual lesions.
A 13.5-year-old Arab boy was diagnosed with FOP. Treatment with anti-inflammatory drugs did not change the disease course. New lumps appeared in a rate of approximately one every 8 days. Treatment with the anti-IL-1 agents anakinra and canakinumab resulted in significantly lower rate of paroxysms (every 22-25 days, of which almost all involved only 2 existing lumps), as well as shorter duration. High levels of IL-1β were found in the patient's plasma samples, collected during a paroxysm that appeared 8 weeks after the last canakinumab dose. In contrast, IL-1β plasma levels were undetectable in the previous three plasma samples, obtained while he was treated with anti-IL-1 agents.
Our data demonstrate the efficacy of anti-IL-1 agents in the treatment of a patient with FOP. Results showing the marked increase in IL-1β plasma levels during a paroxysm support a role for IL-1β in the pathogenesis of FOP and further provide the rationale for the use of anti-IL-1 agents in FOP treatment.
Background and Aims:
Idiopathic pulmonary fibrosis (IPF) is a common and severe form of pulmonary fibrosis. Nintedanib, a triple angiokinase inhibitor, is approved for treating IPF. Galectin 3 ...(Gal-3) activates a variety of profibrotic processes. Currently, the Gal-3 inhibitor TD139 is being tested in phase II clinical trials. Since this treatment is given ‘on top’ of nintedanib, it is important to estimate its effect on Gal-3 levels. Therefore, we evaluated the impact of nintedanib on Gal-3 expression using both in vitro and in vivo models, in addition to serum samples from patients with IPF.
Methods:
Gal-3 levels were evaluated in IPF and control tissue samples, primary human lung fibroblasts (HLFs) following nintedanib treatment (10–100 nM, quantitative polymerase chain reaction), and in a silica-induced fibrosis mouse model with/without nintedanib (0.021–0.21 mg/kg) by immunohistochemistry. In addition, Gal-3 levels were analyzed in serum samples from 41 patients with interstitial lung disease patients with/without nintedanib treatment by ELISA.
Results:
Nintedanib addition to HLFs resulted in significant elevations in Gal-3, phospho-signal transducer and activator of transcription 3 (pSTAT3), as well as IL-8 mRNA levels (p < 0.05). Gal-3 expression was higher in samples from IPF patients compared with non-IPF controls at the protein and mRNA levels (p < 0.05). In the in vivo mouse model, Gal-3 levels were increased following fibrosis induction and even further increased with the addition of nintedanib, mostly in macrophages (p < 0.05). Patients receiving nintedanib presented with higher Gal-3 serum levels compared with those who did not receive nintedanib (p < 0.05).
Conclusion:
Nintedanib elevates Gal-3 levels in both experimental models, along with patient samples. These findings highlight the possibility of using combined inhibition therapy for patients with IPF.
This study examined whether the comic book Neta and the Medikidz Explain JIA would improve disease-related knowledge and treatment adherence among patients with juvenile idiopathic arthritis (JIA).
...In this prospective cohort study, JIA patients answered 20 multiple-choice knowledge questions about their disease, before and after reading the comic book. Demographic, clinical, health-related quality of life and adherence data were recorded and correlated to the responses.
We studied 61 patients with a mean age of 14 ± 3.3 (range 8-18) years, 67% female, 83% Jewish and 17% non-Jewish. Thirty-nine percent had oligoarthritis, 13% systemic, 32% polyarthritis 11% psoriatic and 5% enthesitis-related type JIA. The disease was active in 46%, 40% were treated with biologics/disease modifying anti-rheumatic drugs, and 34% were in remission on medication. Among the 53 patients who completed before and after quizzes, average score increased from 63 to 80% (P < 0.001). Non-Jewish patients initially scored lower than Jewish patients (48%), but their score increased to 79% after reading the comic book. Twenty-seven patients who also completed the quiz 1 year after the first reading retained their knowledge (79%). We did not find a statistically significant correlation between knowledge and age, sex, disease subtype, or Child Health Questionnaire quality of life scores. Adherence to medication use, physical therapy and rheumatology clinic visits were high at baseline; thus, these did not change after reading the comic.
The comic booklet Neta and the Medikidz Explain JIA is a good educational tool for increasing disease-related knowledge in children with JIA.
Pulmonary arterial hypertension (PAH) is a major cause of death in systemic sclerosis (SSc). Early detection may improve patient outcomes.
We searched for circulating miRNAs that would constitute ...biomarkers in SSc patients with PAH (SSc-PAH). We compared miRNA levels and laboratory parameters while evaluating miRNA levels in white blood cells (WBCs) and myofibroblasts.
Our study found: 1) miR-26 and miR-let-7d levels were significantly lower in SSc-PAH (
= 12) versus SSc without PAH (SSc-noPAH) patients (
= 25); 2) a positive correlation between miR-26 and miR-let-7d and complement-C3; 3) GO-annotations of genes that are miR-26/miR-let-7d targets and that are expressed in myofibroblast cells, suggesting that these miRNAs regulate the TGF-β-pathway; 4) reduced levels of both miRNAs accompanied fibroblast differentiation to myofibroblasts, while macitentan (endothelin receptor-antagonist) increased the levels. WBCs of SSc-noPAH and SSc-PAH patients contained equal amounts of miR-26/miR-let-7d. During the study, an echocardiograph that predicted PAH development, showed increased pulmonary artery pressure in three SSc-noPAH patients. At study initiation, those patients and an additional SSc-noPAH patient, who eventually developed PAH, had miR-let-7d/miR-26 levels similar to those of SSc-PAH patients. This implies that reduced miR-let-7d/miR-26 levels might be an early indication of PAH.
miR-26 and miR-let-7d may be serological markers for SSc-PAH. The results of our study suggest their involvement in myofibroblast differentiation and complement pathway activation, both of which are active in PAH development.
Neuropilin-1 (NRP1) is a coreceptor for multiple extracellular ligands. NRP1 is widely expressed in cancer cells and in advanced human tumors; however, its functional relevance and signaling ...mechanisms are unclear. Here, we show that NRP1 expression controls viability and proliferation of different cancer cells, independent of its short intracellular tail. We found that the extracellular domain of NRP1 interacts with the EGF receptor (EGFR) and promotes its signaling cascade elicited upon EGF or TGF-α stimulation. Upon NRP1 silencing, the ability of ligand-bound EGFR to cluster on the cell surface, internalize, and activate the downstream AKT pathway is severely impaired. EGFR is frequently activated in human tumors due to overexpression, mutation, or sustained autocrine/paracrine stimulation. Here we show that NRP1-blocking antibodies and NRP1 silencing can counteract ligand-induced EGFR activation in cancer cells. Thus our findings unveil a novel molecular mechanism by which NRP1 can control EGFR signaling and tumor growth.
Fibrodysplasia ossificans progressiva (FOP) is one of the most catastrophic forms of genetic heterotopic ossification (HO). FOP is characterized by severe, progressive inflammatory flare-ups, that ...often lead to HO. The flare-ups are associated with increased inflammatory cytokine production, suggesting auto-inflammatory features driven by interleukin-1β (IL-1β). This study describes the short- and long-term responses of FOP patients to anti-IL-1 therapy.
Previously, we reported that a patient with FOP treated with anti-IL-1 agents showed dramatically lower rates of flare-ups, improved flare-up symptoms, decreased use of glucocorticoids, and apparently decreased size of residual lesions. Plasma analyses also showed marked elevation in IL-1β levels during a FOP flare, further supporting a role of IL-1β in the pathogenesis of FOP flares. Here, we report results from long-term therapy with IL-1 inhibitors in that patient, and describe 3 additional patients, from two medical centers.
All 4 patients showed persistent improvement in flare activity during treatment with IL-1 inhibitors, with minimal formation of new HO sites. Two patients who stopped therapy experienced resurgence of flare activity that was re-suppressed upon re-initiation. These patients had IL-1β levels comparable to those in IL-1β-driven diseases. Child Health Assessment Questionnaires confirmed extensive subjective improvements in the pain and general health visual analogue scales.
This case series demonstrates significant benefits from IL-1 inhibitors for reducing flare activity and improving the general health of patients with FOP. These data provide strong support for additional studies to better understand the function of IL-1 inhibition, primarily in reducing formation new HO.
RH received support from the International FOP Association ACT grant; ECH received support from NIH/NIAMS R01AR073015 and the UCSF Robert Kroc Chair in Connective Tissue and Rheumatic Diseases III.
To report the temporal association between a series of thromboembolic events and intravenous immunoglobulin infusion in patients with rheumatic diseases, and to review the literature on the subject. ...The clinical presentation, course, and outcome of thromboembolic events occurring post-immunoglobulin infusion in nine patients is described. A web-based literature review using the PubMed database from 1996 to 2017 was performed, searching for the keywords: thrombosis, thromboembolism, intravenous immunoglobulin, pulmonary embolism, deep vein thrombosis, cerebrovascular event, and acute myocardial infarction. Nine patients who had suffered a thromboembolic event within a week after receiving an intravenous immunoglobulin infusion (Omr-IgG-am™, OMRIX) were identified among our joint cohort. All patients except one were female ranging in age from 22 to 69 years. Five had progressive systemic sclerosis (one of them had progressive systemic sclerosis with antiphospholipid syndrome, and another had an overlap of progressive systemic sclerosis with systemic lupus erythematosus), the sixth had monoclonal IgM autoimmune neuropathy, the seventh had systemic lupus erythematosus with antiphospholipid syndrome, the eighth had granulomatosis with polyangiitis (GPA) and the ninth had overlap autoimmune syndrome. Six of the patients had an arterial thrombosis: an acute myocardial infarction in four, a brachial artery thrombosis in the fifth, and a cerebrovascular attack in the sixth. Three patients sustained a venous thrombosis and/or an acute pulmonary embolism (one of them had a DVT with the PE). Two events occurred during the IVIG infusion, three within an hour after the last infusion of the 5-day course, one occurred a few hours after the initiation of the IVIG therapy, another occurred 3 days after receiving the final infusion of the 10th course, and two events occurred a week after the treatment course has ended. Fifty-five percent of the patients had no thrombogenic risk factors other than their rheumatic condition, and most of them had received numerous, uneventful IVIG treatment courses before sustaining the thromboembolic event. No immediate deaths occurred among this cohort. Thromboembolic events after IVIG infusions, although infrequent, may occur in rheumatic patients, even in the absence of other recognizable risk factors for thromboembolism. The reported events had occurred despite complying with recommended guidelines for IVIG administration, which include a lengthy 8-h infusion and division of the total dose. No correlation was found between the number and frequency of the infusions to the thromboembolic events. Heightened awareness of possible thromboembolic events in rheumatic patients is encouraged for at least a week following IVIG administration.
To assess the effect of hypotensive drugs on light absorbance, discoloration, opacification and precipitate formation of IOLs.
In this laboratory study, four types of IOLs (two hydrophilic-acrylic-L1 ...and L2, and two hydrophobic-acrylic-B1 and B2) were soaked in solutions containing Timolol-maleate 0.5%, Dorzolamide 2%, Brimonidine-tartrate 0.2%, Latanoprost 0.005%, Brimonidine-tartrate/Timolol-maleate 0.2%/0.5% and Dorzolamide/Timolol-maleate 2%/0.5%. Non-treated IOLs and IOLs soaked in balanced salt solution (BSS) served as controls. All Treated lenses were sealed in containers and placed in an oven at 82 degrees Celsius for 120 days. Each IOL was examined using four different techniques: light microscopy imaging, light absorbance measurements at 550 nanometers through the optic's center, assessment of by a scanning electron microscope (SEM), and energy dispersive Xray spectrometry (EDX).
Ninety-eight IOLs were included. All BSS-soaked IOLs appeared clear with no significant discoloration or precipitate-formation. Light absorbance in these lenses was comparable to that of non-soaked, non-heated IOLs. No calcium or phosphate were detected in either of these groups. Light absorbance differed significantly between the four treated IOL types. The drops most affecting light absorbance differed between IOLs. Gross examination revealed brown and yellow discoloration of all IOLs soaked in Dorzolamide and Brimonidine-tartrate solutions, respectively. SEM demonstrated precipitates that differed in size, morphology and distribution, between different IOL-solution combinations. EDX's demonstrated the presence calcium and phosphor in the majority of precipitates and the presence of sulfur in brown discolored IOLs.
In vitro, interactions between hypotensive drugs and IOLs induce changes in light absorbance, discoloration and precipitate formation.
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