45 research outputs found
Recommended from our members
Evidence for Pro-angiogenic Functions of VEGF-Ax.
The VEGF-A isoforms play a crucial role in vascular development, and the VEGF signaling pathway is a clinically validated therapeutic target for several pathological conditions. Alternative mRNA splicing leads to the generation of multiple VEGF-A isoforms, including VEGF165. A recent study reported the presence of another isoform, VEGF-Ax, arising from programmed readthrough translation. Compared to VEGF165, VEGF-Ax has a 22-amino-acid extension in the COOH terminus and has been reported to function as a negative regulator of VEGF signaling in endothelial cells, with potent anti-angiogenic effects. Here, we show that, contrary to the earlier report, VEGF-Ax stimulates endothelial cell mitogenesis, angiogenesis, as well as vascular permeability. Accordingly, VEGF-Ax induces phosphorylation of key tyrosine residues in VEGFR-2. Notably, VEGF-Ax was less potent than VEGF165, consistent with its impaired binding to the VEGF co-receptor neuropilin-1
Recommended from our members
Evidence for Pro-angiogenic Functions of VEGF-Ax.
The VEGF-A isoforms play a crucial role in vascular development, and the VEGF signaling pathway is a clinically validated therapeutic target for several pathological conditions. Alternative mRNA splicing leads to the generation of multiple VEGF-A isoforms, including VEGF165. A recent study reported the presence of another isoform, VEGF-Ax, arising from programmed readthrough translation. Compared to VEGF165, VEGF-Ax has a 22-amino-acid extension in the COOH terminus and has been reported to function as a negative regulator of VEGF signaling in endothelial cells, with potent anti-angiogenic effects. Here, we show that, contrary to the earlier report, VEGF-Ax stimulates endothelial cell mitogenesis, angiogenesis, as well as vascular permeability. Accordingly, VEGF-Ax induces phosphorylation of key tyrosine residues in VEGFR-2. Notably, VEGF-Ax was less potent than VEGF165, consistent with its impaired binding to the VEGF co-receptor neuropilin-1
Recommended from our members
Interleukin-22 promotes tumor angiogenesis.
TH17 cells play important yet complex roles in cancer development and progression. We previously reported that TH17 cells and IL-17 mediate resistance to anti-VEGF therapy by inducing recruitment of immunosuppressive and proangiogenic myeloid cells to the tumor microenvironment. Here, we demonstrate that IL-22, a key effector cytokine expressed by TH17 cells, directly acts on endothelial cells to promote tumor angiogenesis. IL-22 induces endothelial cell proliferation, survival, and chemotaxis in vitro and neovascularization in an ex vivo mouse choroid explant model. Blockade of IL-22, with a neutralizing antibody, significantly inhibits tumor growth associated with reduced microvascular density. No synergistic effect of IL-22 with VEGF was observed. These results identify IL-22 as a potential therapeutic target for blocking tumor angiogenesis
Recommended from our members
Interleukin-22 promotes tumor angiogenesis.
TH17 cells play important yet complex roles in cancer development and progression. We previously reported that TH17 cells and IL-17 mediate resistance to anti-VEGF therapy by inducing recruitment of immunosuppressive and proangiogenic myeloid cells to the tumor microenvironment. Here, we demonstrate that IL-22, a key effector cytokine expressed by TH17 cells, directly acts on endothelial cells to promote tumor angiogenesis. IL-22 induces endothelial cell proliferation, survival, and chemotaxis in vitro and neovascularization in an ex vivo mouse choroid explant model. Blockade of IL-22, with a neutralizing antibody, significantly inhibits tumor growth associated with reduced microvascular density. No synergistic effect of IL-22 with VEGF was observed. These results identify IL-22 as a potential therapeutic target for blocking tumor angiogenesis
Evaluation of Visunex Medical's PanoCam(TM) LT and PanoCam(TM) Pro wide-field imaging systems for the screening of ROP in newborn infants
Retinopathy of Prematurity (ROP) is a leading cause of childhood blindness. The incidence of ROP is rising, placing greater demands on the healthcare providers that serve these patients and their families. Telemedicine remote digital fundus imaging (TM-RDFI) plays a pivotal role in ROP management, and has allowed for the expansion of ROP care into previously underserved areas.
A broad literature review through the pubmed index was undertaken with the goal of summarizing the current state of ROP and guidelines for its screening . Furthermore, all currently used telemedicine remote digital fundus imaging devices were analyzed both via the literature and the companies' websites/brochures. Finally, the PanoCam LT™ and PanoCam™ Pro created by Visunex Medical were analyzed via the company website/brochures. Expert commentary: The PanoCam LT™ and PanoCam™ Pro have recently been approved for use within the USA and CE marked for international commercialization in European Union and other countries requiring CE mark. These wide-field imaging systems have the intended use of ophthalmic imaging of all newborn babies and meet the requirements for ROP screening, thereby serving as competition within the ROP screening market previously dominated by one camera imaging system
Recommended from our members
Long-term surgical outcomes of retinal detachment in patients with Stickler syndrome
Purpose The aim of the study was to present the long-term anatomical and visual outcomes of retinal detachment repair in patients with Stickler syndrome. Patients and methods This study is a retrospective, interventional, consecutive case series of patients with Stickler syndrome undergoing retinal reattachment surgery from 2009 to 2014 at the Associated Retinal Consultants, William Beaumont Hospital. Results: Sixteen eyes from 13 patients were identified. Patients underwent a mean of 3.1 surgical interventions (range: 1–13) with a mean postoperative follow-up of 94 months (range: 5–313 months). Twelve eyes (75%) developed proliferative vitreoretinopathy. Retinal reattachment was achieved in 100% of eyes, with ten eyes (63%) requiring silicone oil tamponade at final follow-up. Mean preoperative visual acuity (VA) was 20/914, which improved to 20/796 at final follow-up (P=0.81). There was a significant correlation between presenting and final VA (P<0.001), and patients with poorer presenting VA were more likely to require silicone oil tamponade at final follow-up (P=0.04). Conclusion: Repair of retinal detachment in patients with Stickler syndrome often requires multiple surgeries, and visual outcomes are variable. Presenting VA is significantly predictive of long-term VA outcomes
Pulling Together with Type IV Pili Where Are Type IV Pili Found?
Abstract Type IV pili are an efficient and versatile device for bacterial surface motility. They are widespread among the ß-, Á-, and ‰-proteobacteria and the cyanobacteria. Within that diversity, there is a core of conserved proteins that includes the pilin (PilA), the motors PilB and PilT, and various components of pilus biogenesis and assembly, PilC, PilD, PilM, PilN, PilO, PilP, and PilQ. Progress has been made in understanding the motor and the secretory functions. PilT is a motor protein that catalyzes pilus retraction; PilB may play a similar role in pilus extension. Type IV pili are multifunctional complexes that can act as bacterial virulence factors because pilus-based motility is used to spread pathogens over the surface of a tissue, or to build multicellular structures such as biofilms and fruiting bodies
Heparin-binding VEGFR1 variants as long-acting VEGF inhibitors for treatment of intraocular neovascular disorders.
Neovascularization is a key feature of ischemic retinal diseases and the wet form of age-related macular degeneration (AMD), all leading causes of severe vision loss. Vascular endothelial growth factor (VEGF) inhibitors have transformed the treatment of these disorders. Millions of patients have been treated with these drugs worldwide. However, in real-life clinical settings, many patients do not experience the same degree of benefit observed in clinical trials, in part because they receive fewer anti-VEGF injections. Therefore, there is an urgent need to discover and identify novel long-acting VEGF inhibitors. We hypothesized that binding to heparan-sulfate proteoglycans (HSPG) in the vitreous, and possibly other ocular structures, may be a strategy to promote intraocular retention, ultimately leading to a reduced burden of intravitreal injections. We designed a series of VEGF receptor 1 variants and identified some with strong heparin-binding characteristics and ability to bind to vitreous matrix. Our data indicate that some of our variants have longer duration and greater efficacy in animal models of intraocular neovascularization than current standard of care. Our study represents a systematic attempt to exploit the functional diversity associated with heparin affinity of a VEGF receptor
Advances in Retinopathy of Prematurity Imaging
Retinopathy of prematurity (ROP) remains the leading cause of childhood blindness worldwide. Recent advances in ROP imaging have significantly improved our understanding of the pathogenesis and pathophysiological course of ROP including the acute phase, regression, reactivation, and late complications, known as adult ROP. Recent progress includes various contact and noncontact wide-field imaging devices for fundus imaging, smartphone-based fundus photography, wide-field fluorescein angiography, handheld optical coherence tomography (OCT) devices for wide-field en face OCT images, and OCT angiography. Images taken by those devices were incorporated in the recently updated guidelines of ROP, the International Classification of Retinopathy of Prematurity, Third Edition (ICROP3). ROP imaging has also allowed the real-world adoption of telemedicine- and artificial intelligence (AI)-based screening. Recent study demonstrated proof of concept that AI has a high diagnostic performance for the detection of ROP in a real-world screening. Here, we summarize the recent advances in ROP imaging and their application for screening, diagnosis, and management of ROP