bioRxiv ScienceSearch

bioRxiv · 10.1101/2020.07.25.218149

A Humanized Antibody against LRG1 that Inhibits Angiogenesis and Reduces Retinal Vascular Leakage

Abstract

Pathological angiogenesis contributes to morbidity in a number of diseases including cancer, diabetic retinopathy and the neovascular form of age-related macular degeneration, leading to significant efforts to develop effective anti-angiogenic therapeutics for these conditions. The field is dominated by inhibitors of vascular endothelial growth factor (VEGF), yet angiogenesis can also be driven and modified by other factors. We have previously demonstrated that leucine-rich alpha-2-glycoprotein 1 (LRG1) contributes to abnormal vessel growth by activating a TGF{beta} switch. Here we report the development and characterisation of a function-blocking fully humanised IgG4 and its Fab fragment, that bind to LRG1 with high affinity and specificity and inhibit vascular leakage in the mouse model of laser-induced choroidal neovascularisation. In summary, we have developed a therapeutic antibody that targets a VEGF-independent signalling axis, which may be effective in a number of conditions either as monotherapy or in combination with other vascular targeted therapies.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Kallenberg, D., Tripathi, V., Javaid, F., Pilotti, C., George, J., Davis, S., Blackburn, J. W., O'Connor, M., Dowsett, L., Bowers, C., Liyanage, S. E., Gourlaouen, M., Hoeh, A., Mota, F., Selwood, D., Bainbridge, J., Chudasama, V., Greenwood, J., Moss, S. E.. 2020-07-25. A Humanized Antibody against LRG1 that Inhibits Angiogenesis and Reduces Retinal Vascular Leakage. https://doi.org/10.1101/2020.07.25.218149

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

NAE1-Dependent Protein Neddylation Preserves Endothelial Identity and Vascular Integrity

Background: Endothelial dysfunction is a central driver of cardiovascular and inflammatory diseases, yet the post-translational mechanisms that preserve endothelial homeostasis remain incompletely understood. Protein neddylation, the covalent conjugation of a ubiquitin-like modifier, regulates diverse cellular processes, yet its physiological role in the vascular endothelium remains unknown. This study investigated whether protein neddylation is required to preserve endothelial identity and vascular homeostasis. Methods: We generated tamoxifen-inducible endothelial-specific Nae1 knockout mice to inhibit neddylation and combined bulk RNA sequencing, single-cell and single-nucleus transcriptomics, quantitative proteomics, biochemical analyses, and gain- and loss-of-function approaches to define the role of endothelial neddylation in vascular homeostasis and inflammatory injury. Results: Endothelial-specific Nae1 deletion caused rapid mortality associated with vascular leakage, platelet accumulation, inflammation, and multi-organ injury. Multi-omics analyses demonstrated profound loss of endothelial identity, characterized by suppression of core endothelial programs and activation of inflammatory, procoagulant, and pyroptotic pathways. Single-cell analyses revealed progressive endothelial dysfunction culminating in depletion of the endothelial population and remodeling of the vascular niche. Mechanistically, endothelial neddylation deficiency activated gasdermin D (GSDMD)- and gasdermin E (GSDME)-dependent pyroptosis, whereas dual inhibition of GSDMD and GSDME markedly attenuated inflammatory transcriptomic remodeling, vascular injury, hepatocyte death, immune cell infiltration, and platelet accumulation. Translational analyses demonstrated reduced endothelial neddylation in experimental endotoxemia and decreased expression of neddylation pathway components in human atherosclerosis and COVID-19 datasets. Conversely, restoration of endothelial neddylation partially reversed inflammatory endothelial transcriptomic reprogramming in vivo. Conclusions: NAE1-dependent protein neddylation is an essential regulator of endothelial identity and vascular integrity. Loss of endothelial neddylation promotes gasdermin-dependent pyroptosis and thrombo-inflammatory vascular injury, whereas restoration of the neddylation pathway mitigates inflammatory endothelial dysfunction. These findings identify endothelial neddylation as a fundamental mechanism maintaining vascular homeostasis and a potential therapeutic target for cardiovascular and inflammatory diseases.

pathology

Using Progressive Context Encoders for Anomaly Detection in Digital Pathology Images

Whole slide imaging (WSI) is transforming the practice of pathology, converting a qualitative discipline into a quantitative one. However, one must exercise caution in interpreting algorithm assertions, particularly in pathology where an incorrect classification could have profound impacts on a patient, and rare classes exist that may not have been seen by the algorithm during training. A more robust approach would be to identify areas of an image for which the pathologist should concentrate their effort to make a final diagnosis. This anomaly detection strategy would be ideal for WSI, but given the extremely high resolution and large file sizes, such an approach is difficult. Here, we combine progressive generative adversarial networks with a flexible adversarial autoencoder architecture capable of learning the "normal distribution" of WSIs of normal skin tissue at extremely high resolution and demonstrate its anomaly detection performance. Our approach yielded pixel-level accuracy of 89% for identifying melanoma, suggesting that our label-free anomaly detection pipeline is a viable strategy for generating high quality annotations - without tedious manual segmentation by pathologists. The code is publicly available at https://github.com/Steven-N-Hart/P-CEAD.

pathology

Atherosis of trophoblast type: A specific form of decidual vasculopathy distinct from atherosis of macrophage type

BackgroundThere are three types of decidual vasculopathy, namely, acute atherosis, fibrinoid medial necrosis and mural arterial hyerptrophy. Persistence of vascular trophoblasts is also known to be related to maternal vascular malperfusion, but detailed study is lacking. Material and methodsA total 1017 placentas from 2021 were collected with clinical, neonatal and placental information, and routine placental pathology examination was performed. Decidual vasculopathy was classified based on the new classification scheme including atherosis of macrophage type atherosis of trophoblast type, fibrinoid medial necrosis, mural arterial hypertrophy and mixed type vasculopathy. The significance of these morphologic changes were examined based on the clinical, neonatal and placental pathology features. ResultsDecidual vasculopathy is classified as classic type, mural hypertrophy and mixed type. Classic type vasculopathy is further separated as atherosis and fibrinoid medial necrosis. Atherosis is defined as atherosis of macrophage type and atherosis of trophoblast type. Each category of decidual vasculopathy was evaluated in association with maternal, neonatal and placental pathologic findings. Atherosis of macrophage type and mixed type vasculopathy showed statistically significant association with preeclampsia/pregnancy induced hypertension, low birth weight and low placental weight. Atherosis of trophoblast type was associated with lower placental weight but not with specific clinical features. There is no neonatal sex dimorphism in decidual vasculopathy. ConclusionAtherosis of trophoblast type is a distinct pathologic feature in late pregnancy, and it is associated with lower placental weight. New classification of decidual vasculopathy helps with better stratification and categorization of placental maternal vascular abnormalities.

pathology