Elastin-like recombinamer hydrogels as platforms for breast cancer modeling

The involvement of the extracellular matrix (ECM) in tumor progression has motivated the development of biomaterials mimicking the tumor ECM to develop more predictive cancer models. Particularly, polypeptides based on elastin could be an interesting approach to mimic the ECM due to their tunable properties. Here, we demonstrated that elastin-like recombinamer (ELR) hydrogels can be suitable biomaterials to develop breast cancer models. This hydrogel was formed by two ELR polypeptides, one containing sequences biodegradable by matrix metalloproteinase and cyclooctyne and the other carrying arginylglycylaspartic acid and azide groups to allow cell adhesion, biodegradability, and suitable stiffness through “click-chemistry” cross-linking. Our findings show that breast cancer or nontumorigenic breast cells showed high viability and cell proliferation for up to 7 days. MCF7 and MCF10A formed spheroids whereas MDA-MB-231 formed cell networks, with the expression of ECM and high drug resistance in all cases, evidencing that ELR hydrogels are a promising biomaterial for breast cancer modeling.Peer ReviewedPostprint (published version

Biofunctionalization of REDV elastin-like recombinamers improves endothelialization on CoCr alloy surfaces for cardiovascular applications

To improve cardiovascular implant success, metal-based stents are designated to modulate endothelial cells adhesion and migration in order to prevent restenosis and late thrombosis diseases. Biomimetic coatings with extra-cellular matrix adhesive biomolecules onto stents surfaces are a strategy to recover a healthy endothelium. However, the appropriate bioactive sequences to selective promote growth of endothelium and the biomolecules surface immobilization strategy remains to be elucidated. In this study, biofunctionalization of cobalt chromium, CoCr, alloy surfaces with elastin-like recombinamers, ELR, genetically modified with an REDV sequence, was performed to enhance metal surfaces endothelialization. Moreover, physical adsorption and covalent bonding were used as biomolecules binding strategies onto CoCr alloy. Surfaces were activated with plasma and etched with sodium hydroxide previous to silanization with 3-chloropropyltriethoxysilane and functionalized with the ELR. CoCr alloy surfaces were successfully biofunctionalized and the use of an ELR with an REDV sequence, allows conferring bioactivity to the biomaterials surface, demonstrating a higher cell adhesion and spreading of HUVEC cells on the different CoCr surfaces. This effect is emphasized as increases the amount of immobilized biomolecules and directly related to the immobilization technique, covalent bonding, and the increase of surface charge electronegativity. Our strategy of REDV elastin-like recombinamers immobilization onto CoCr alloy surfaces via covalent bonding through organosilanes provides a bioactive surface that promotes endothelial cell adhesion and spreading. (C) 2015 Elsevier B.V. All rights reserved.Peer ReviewedPostprint (author’s final draft

Development of tailored and self-mineralizing citric acid-crosslinked hydrogels for in situ bone regeneration

Bone tissue engineering demands alternatives overcoming the limitations of traditional approaches in the context of a constantly aging global population. In the present study, elastin-like recombinamers hydrogels were produced by means of carbodiimide-catalyzed crosslinking with citric acid, a molecule suggested to be essential for bone nanostructure. By systematically studying the effect of the relative abundance of reactive species on gelation and hydrogel properties such as functional groups content, degradation and structure, we were able to understand and to control the crosslinking reaction to achieve hydrogels mimicking the fibrillary nature of the extracellular matrix. By studying the effect of polymer concentration on scaffold mechanical properties, we were able to produce hydrogels with a stiffness value of 36.13 +/- 10.72 kPa, previously suggested to be osteoinductive. Microstructured and mechanically-tailored hydrogels supported the growth of human mesenchymal stem cells and led to higher osteopontin expression in comparison to their non-tailored counterparts. Additionally, tailored hydrogels were able to rapidly self-mineralize in biomimetic conditions, evidencing that citric acid was successfully used both as a crosslinker and a bioactive molecule providing polymers with calcium phosphate nucleation capacity. (C) 2015 Elsevier Ltd. All rights reserved.Postprint (author's final draft

Formation of calcium phosphate nanostructures under the influence of self-assembling hybrid elastin-like-statherin recombinamers

The self-assembling properties of thermally-sensitive amphiphilic elastin-like multiblock recombinamers have been combined with the capacities of calcium phosphate binding of the SN(A)15 epitope inspired by the salivary protein statherin. In this regard, the interaction between calcium and phosphate ions was examined in the presence of two hybrid recombinamers. The first recombinamer comprised a simple amphiphilic diblock in which the SN(A)15 epitopes were combined, at the gene level, to the hydrophilic end. This recombinamer can self-assemble into nanoparticles that can control the transformation of amorphous calcium phosphate (ACP) into a fibre-like hydroxyapatite structure. In the other recombinamer, the SN(A)15 domains are distributed along the monomer chain, with the hydrophilic blocks being distributed amongst the hydrophobic ones. In this case, the resulting nanohybrid ACP/recombinamer organises into neuron-like structures. Thus, combining the amphiphilic elastin-like recombinamers to the SN(A)15 functionality is a powerful mean to tune the formation of different complex calcium phosphate nanostructures.Peer ReviewedPostprint (author's final draft

Interfacial Self-Assembly to Spatially Organize Graphene Oxide Into Hierarchical and Bioactive Structures

Multicomponent self-assembly holds great promise for the generation of complex and functional biomaterials with hierarchical microstructure. Here, we describe the use of supramolecular co-assembly between an elastin-like recombinamer (ELR5) and a peptide amphiphile (PA) to organise graphene oxide (GO) flakes into bioactive structures across multiple scales. The process takes advantage of a reaction – diffusion mechanism to enable the incorporation and spatial organization of GO within multiple ELR5/PA layers. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and ImageJ software were used to demonstrate the hierarchical organisation of GO flakes within the ELR5/PA layers and the distribution profiles of GO throughout the ELR5/PA membranes. Furthermore,atomic force microscopy (AFM) revealed improved Young’s moduli of the ELR5/PA/GOmembranes compared to the ELR5/PA membranes. Lastly, we investigated biocompatibility of the ELR5/PA/GO membrane via various cell culture methods

Peptide-Protein Coassemblies into Hierarchical and Bioactive Tubular Membranes

Multicomponent self-assembly offers opportunities for the design of complex and functional biomaterials with tunable properties. Here, we demonstrate how minor modifications in the molecular structures of peptide amphiphiles (PAs) and elastin-like recombinamers (ELs) can be used to generate coassembling tubular membranes with distinct structures, properties, and bioactivity. First, by introducing minor modifications in the charge density of PA molecules (PAK2, PAK3, PAK4), different diffusion-reaction processes can be triggered, resulting in distinct membrane microstructures. Second, by combining different types of these PAs prior to their coassembly with ELs, further modifications can be achieved, tuning the structures and properties of the tubular membranes. Finally, by introducing the cell adhesive peptide RGDS in either the PA or EL molecules, it is possible to harness the different diffusion-reaction processes to generate tubular membranes with distinct bioactivities. The study demonstrates the possibility to trigger and achieve minor but crucial differences in coassembling processes and tune material structure and bioactivity. The study demonstrates the possibility to use minor, yet crucial, differences in coassembling processes to tune material structure and bioactivity

An interfacial self-assembling bioink for the manufacturing of capillary-like structures with tuneable and anisotropic permeability

Self-assembling bioinks offer the possibility to biofabricate with molecular precision, hierarchical control, and biofunctionality. For this to become a reality with widespread impact, it is essential to engineer these ink systems ensuring reproducibility and providing suitable standardization. We have reported a self-assembling bioink based on disordered-to-ordered transitions of an elastin-like recombinamer (ELR) to co-assemble with graphene oxide (GO). Here, we establish reproducible processes, optimize printing parameters for its use as a bioink, describe new advantages that the self-assembling bioink can provide, and demonstrate how to fabricate novel structures with physiological relevance. We fabricate capillary-like structures with resolutions down to ~10 µm in diameter and ~2 µm thick tube walls and use both experimental and finite element analysis to characterize the printing conditions, underlying interfacial diffusion-reaction mechanism of assembly, printing fidelity, and material porosity and permeability. We demonstrate the capacity to modulate the pore size and tune the permeability of the resulting structures with and without human umbilical vascular endothelial cells (hUVECs). Finally, the potential of the ELR-GO bioink to enable supramolecular fabrication of biomimetic structures was demonstrated by printing tubes exhibiting walls with progressively different structure and permeability

How does neighbourhood socio-economic status affect the interrelationships between functioning dimensions in first episode of psychosis? A network analysis approach

The links between psychosis and socio-economic disadvantage have been widely studied. No previous study has analysed the interrelationships and mutual influences between functioning dimensions in first episode of psychosis (FEP) according to their neighbourhood household income, using a multidimensional and transdiagnostic perspective. 170 patients and 129 controls, participants in an observational study (AGES-CM), comprised the study sample. The WHO Disability Assessment Schedule (WHODAS 2.0) was used to assess functioning, whereas participants' postcodes were used to obtain the average household income for each neighbourhood, collected by the Spanish National Statistics Institute (INE). Network analyses were conducted with the aim of defining the interrelationships between the different dimensions of functioning according to the neighbourhood household income. Our results show that lower neighbourhood socioeconomic level is associated with lower functioning in patients with FEP. Moreover, our findings suggest that “household responsibilities” plays a central role in the disability of patients who live in low-income neighbourhoods, whereas “dealing with strangers” is the most important node in the network of patients who live in high-income neighbourhoods. These results could help to personalize treatments, by allowing the identification of potential functioning areas to be prioritized in the treatment of FEP according to the patient's neighbourhood characteristic

The interplay between functioning problems and symptoms in first episode of psychosis: an approach from network analysis

The relationship between psychotic symptoms and global measures of functioning has been widely studied. No previous study has assessed so far the interplay between specific clinical symptoms and particular areas of functioning in first-episode psychosis (FEP) using network analysis methods. A total of 191 patients with FEP (age 24.45 ± 6.28 years, 64.9% male) participating in an observational and longitudinal study (AGES-CM) comprised the study sample. Functioning problems were assessed with the WHO Disability Assessment Schedule (WHODAS), whereas the Positive and Negative Syndrome Scale (PANSS) was used to assess symptom severity. Network analysis were conducted with the aim of analysing the patterns of relationships between the different dimensions of functioning and PANSS symptoms and factors at baseline. According to our results, the most important nodes were “conceptual disorganization”, “emotional withdrawal”, “lack of spontaneity and flow of conversation”, “delusions”, “unusual thought content”, “dealing with strangers” and “poor rapport”. Our findings suggest that these symptoms and functioning dimensions should be prioritized in the clinical assessment and management of patients with FEP. These areas may also become targets of future early intervention strategies, so as to improve quality of life in this populationThis work was supported by the Madrid Regional Government (R&D activities in Biomedicine (grant number S2017/BMD-3740 - AGES-CM 2-CM)) and Structural Funds of the European Union. Ana Izquierdo’s work is supported by the PFIS predoctoral program (FI17/00138) from the Instituto de Salud Carlos III (Spain) and co-funded by the European Union (ERDF/ESF, "A way to make Europe”/ “Investing in your future”) and The Biomedical Research Foundation of La Princesa University Hospital. Angela Ib´a˜nez thanks the support of CIBERSAM and of the Spanish Ministry of Science, Innovation and Universities. Instituto de Salud Carlos III (PI16/00834 and PI19/01295) co-financed by ERDF Funds from the European Commission. Covadonga M. Díaz-Caneja holds a Juan Rod´es Grant from Instituto de Salud Carlos III (JR19/00024). Celso Arango was supported by the Spanish Ministry of Science and Innovation. Instituto de Salud Carlos III (SAM16PE07CP1, PI16/02012, PI19/ 024), co-financed by ERDF Funds from the European Commission, “A way of making Europe”, CIBERSAM. Madrid Regional Government (B2017/BMD-3740 AGES-CM-2), European Union Structural Funds. European Union Seventh Framework Program under grant agreements FP7-4-HEALTH-2009-2.2.1-2-241909 (Project EU-GEI), FP7- HEALTH- 2013-2.2.1-2-603196 (Project PSYSCAN) and FP7- HEALTH-2013- 2.2.1-2-602478 (Project METSY); and European Union H2020 Program under the Innovative Medicines Initiative 2 Joint Undertaking (grant agreement No 115916, Project PRISM, and grant agreement No 777394, Project AIMS-2-TRIALS), Fundaci´on Familia Alonso, Fundaci´on Alicia Koplowitz and Fundaci´on Mutua Madrile˜n

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality