Kinase-insert domain-containing receptor (KDR) is one of the important mediators of Vascular endothelial growth factor (VEGF) function in endothelial cells. Inhibition of KDR can be therapeutically ...advantageous for treatment of a number of diseases. The present study focuses on exploring novel KDR inhibitors by means of pharmaco-informatics methodologies. Three-dimensional quantitative structure-activity relationship (3D-QSAR) analysis by atom-based pharmacophore mapping over a set of 85 molecules provides a proposition regarding the molecular fingerprint that can be optimized for designing more active inhibitors. The model was statistically validated with Q
2
= 0.865 for training and r
2
= 0.789, Pearson-r = 0.903 for test set molecules; r
2
(0.925) by external validation suggests model robustness and indicates it as a strong query for screening any compound library. Virtual screening shows the importance of active site and hinge region residue for interaction with KDR inhibitors. Remarkably the retrieved hits contain a urea backbone, implicating urea derivatives as promising candidate for designing KDR inhibitors. The hydrophobicity of active site, which has until now been overlooked, has been raised into the picture by this study. This can impact on KDR drug development. The study thus quantifies crucial structural requirements necessary for a favourable interaction with the receptor binding site while the cooperative pattern provides important structural clues to chemists for framing potent medicinal agents in future.
Antibodies targeting the SARS-CoV-2 spike receptor-binding domain (RBD) are being developed as therapeutics and are a major contributor to neutralizing antibody responses elicited by infection. Here, ...we describe a deep mutational scanning method to map how all amino-acid mutations in the RBD affect antibody binding and apply this method to 10 human monoclonal antibodies. The escape mutations cluster on several surfaces of the RBD that broadly correspond to structurally defined antibody epitopes. However, even antibodies targeting the same surface often have distinct escape mutations. The complete escape maps predict which mutations are selected during viral growth in the presence of single antibodies. They further enable the design of escape-resistant antibody cocktails—including cocktails of antibodies that compete for binding to the same RBD surface but have different escape mutations. Therefore, complete escape-mutation maps enable rational design of antibody therapeutics and assessment of the antigenic consequences of viral evolution.
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•Develop system to map all SARS-CoV-2 RBD mutations that escape antibody binding•Escape maps predict which mutations emerge when virus grown in presence of antibody•Escape maps inform surveillance for possible antigenic evolution
Greaney et al. develop a method to map all mutations to the SARS-CoV-2 RBD that escape antibody binding and apply this method to 10 antibodies. The resulting escape maps predict which mutations arise when virus is grown in the presence of antibody and can inform the design of antibody therapeutics.
A general, concise, and efficient strategy for the enantioselective synthesis of the eburnane alkaloid family of natural products is disclosed. Specifically, 13 members of the natural product family ...were prepared from commercially available and inexpensive starting materials. The brevity and modularity of the route are largely on account of a two-phase synthesis logic and a key catalytic enantioconvergent cross-coupling to establish the C20 stereogenic center. The strategies described here are expected to facilitate in-depth biological studies and provide access to new anticancer eburnane analogues.
The ongoing pandemic of coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a major threat to global health
and the medical ...countermeasures available so far are limited
. Moreover, we currently lack a thorough understanding of the mechanisms of humoral immunity to SARS-CoV-2
. Here we analyse a large panel of human monoclonal antibodies that target the spike (S) glycoprotein
, and identify several that exhibit potent neutralizing activity and fully block the receptor-binding domain of the S protein (S
) from interacting with human angiotensin-converting enzyme 2 (ACE2). Using competition-binding, structural and functional studies, we show that the monoclonal antibodies can be clustered into classes that recognize distinct epitopes on the S
, as well as distinct conformational states of the S trimer. Two potently neutralizing monoclonal antibodies, COV2-2196 and COV2-2130, which recognize non-overlapping sites, bound simultaneously to the S protein and neutralized wild-type SARS-CoV-2 virus in a synergistic manner. In two mouse models of SARS-CoV-2 infection, passive transfer of COV2-2196, COV2-2130 or a combination of both of these antibodies protected mice from weight loss and reduced the viral burden and levels of inflammation in the lungs. In addition, passive transfer of either of two of the most potent ACE2-blocking monoclonal antibodies (COV2-2196 or COV2-2381) as monotherapy protected rhesus macaques from SARS-CoV-2 infection. These results identify protective epitopes on the S
and provide a structure-based framework for rational vaccine design and the selection of robust immunotherapeutic agents.
Isocitrate dehydrogenase (
)-mutant glioma is a distinct glioma molecular subtype for which no effective molecularly directed therapy exists. Low-grade gliomas, which are 80%-90%
-mutant, have high ...RNA levels of the cell surface Notch ligand DLL3. We sought to determine DLL3 expression by IHC in glioma molecular subtypes and the potential efficacy of an anti-DLL3 antibody-drug conjugate (ADC), rovalpituzumab tesirine (Rova-T), in
-mutant glioma.
We evaluated
expression by RNA using TCGA data and by IHC in a discovery set of 63 gliomas and 20 nontumor brain tissues and a validation set of 62 known
wild-type and mutant gliomas using a monoclonal anti-DLL3 antibody. Genotype was determined using a DNA methylation array classifier or by sequencing. The effect of Rova-T on patient-derived endogenous
-mutant glioma tumorspheres was determined by cell viability assay.
Compared to
wild-type glioblastoma,
-mutant gliomas have significantly higher
RNA (
< 1 × 10
) and protein by IHC (
= 0.0014 and
< 4.3 × 10
in the discovery and validation set, respectively). DLL3 immunostaining was intense and homogeneous in
-mutant gliomas, retained in all recurrent tumors, and detected in only 1 of 20 nontumor brains. Patient-derived
-mutant glioma tumorspheres overexpressed DLL3 and were potently sensitive to Rova-T in an antigen-dependent manner.
DLL3 is selectively and homogeneously expressed in
-mutant gliomas and can be targeted with Rova-T in patient-derived
-mutant glioma tumorspheres. Our findings are potentially immediately translatable and have implications for therapeutic strategies that exploit cell surface tumor-associated antigens.
A wide spectrum of clinical manifestations has become a hallmark of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) COVID-19 pandemic, although the immunological underpinnings of ...diverse disease outcomes remain to be defined. We performed detailed characterization of B cell responses through high-dimensional flow cytometry to reveal substantial heterogeneity in both effector and immature populations. More notably, critically ill patients displayed hallmarks of extrafollicular B cell activation and shared B cell repertoire features previously described in autoimmune settings. Extrafollicular activation correlated strongly with large antibody-secreting cell expansion and early production of high concentrations of SARS-CoV-2-specific neutralizing antibodies. Yet, these patients had severe disease with elevated inflammatory biomarkers, multiorgan failure and death. Overall, these findings strongly suggest a pathogenic role for immune activation in subsets of patients with COVID-19. Our study provides further evidence that targeted immunomodulatory therapy may be beneficial in specific patient subpopulations and can be informed by careful immune profiling.
This book provides the latest information on a mainstream process that is critical for high-volume, high-yield semiconductor manufacturing, and even more so as device dimensions continue to shrink. ...The technology has grown to encompass the removal and planarization of multiple metal and dielectric materials and layers both at the device and the metallization levels, using different tools and parameters, requiring improvements in the control of topography and defects. This important book offers a systematic review of fundamentals and advances in the area.
•Obstacles for CED of CAR T cells are sedimentation, tube clogging, low viability.•LV Hydrogel is a biodegradable hyaluronic acid based biomaterial.•LV Hydrogel provides 20-fold increase in the ...delivery rate of CAR T cells.•Migration capacity and cytotoxicity of CAR T cells remain the same after infusion.•LV hydrogel has no toxic effect on rodent brain and fully disintegrated after 2 weeks.
Convection Enhanced Delivery (CED) infuses therapeutic agents directly into the intracranial area continuously under pressure. The convection improves the distribution of therapeutics such as those aimed at brain tumors. Although CED successfully delivers small therapeutic agents, this technique fails to effectively deliver cells largely due to cell sedimentation during delivery. To overcome this limitation, we have developed a low viscosity hydrogel (LVHydrogel), which is capable of retaining cells in suspension. In this study, we evaluated whether LVHydrogel can effectively act as a carrier for the CED of tumor-specific chimeric antigen receptor (CAR) T cells. CAR T cells were resuspended in saline or LVHydrogel carriers, loaded into syringes, and passed through the CED system for 5 h. CAR T cells submitted to CED were counted and the efficiency of delivery was determined. In addition to delivery, the ability of CAR T cells to migrate and induce cytotoxicity was evaluated. Our studies demonstrate that LVHydrogel is a superior carrier for CED in comparison to saline. The efficiency of cell delivery in saline carrier was only ∼3–5% of the total cells whereas delivery by the LVHydrogel carrier was much higher, reaching ∼45–75%. Migration and Cytotoxicity was similar in both carriers in non-infused samples but we found superior cytotoxicity in LVHydrogel group post-infusion. We demonstrate that LVHydrogel, a biodegradable biomaterial which does not cause acute toxicity on preclinical animal models, prevents cellular sedimentation during CED and presents itself as a superior carrier to the current carrier, saline, for the CED of CAR T cells.
Immunotherapeutic approaches to cancer have shown remarkable promise. A critical barrier to successfully executing such immune-mediated interventions is the selection of safe yet immunogenic targets. ...As patient deaths have occurred when tumor-associated antigens shared by normal tissue have been targeted by strong cellular immunotherapeutic platforms, route of delivery, target selection and the immune-mediated approach undertaken must work together to maximize efficacy with safety. Selected tumor-specific targets can spare potential toxicity to normal tissue; however, they are far less common than tumor-associated antigens and may not be present on all patients. In the context of immunotherapy for high-grade glioma, 2 of the most prominently studied antigens are the tumor-associated epidermal growth factor receptor and its tumor-specific genetic deletion variant III. In this review, we will summarize the immune-mediated strategies employed against these targets as well as the caveats particular to these approaches.
Antibodies are a principal determinant of immunity for most RNA viruses and have promise to reduce infection or disease during major epidemics. The novel coronavirus SARS-CoV-2 has caused a global ...pandemic with millions of infections and hundreds of thousands of deaths to date
. In response, we used a rapid antibody discovery platform to isolate hundreds of human monoclonal antibodies (mAbs) against the SARS-CoV-2 spike (S) protein. We stratify these mAbs into five major classes on the basis of their reactivity to subdomains of S protein as well as their cross-reactivity to SARS-CoV. Many of these mAbs inhibit infection of authentic SARS-CoV-2 virus, with most neutralizing mAbs recognizing the receptor-binding domain (RBD) of S. This work defines sites of vulnerability on SARS-CoV-2 S and demonstrates the speed and robustness of advanced antibody discovery platforms.
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