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Mata, A.

Publications and source records attributed to Mata, A..

4 recordsLinked to original sources

Bioconvergence of sound-guided and supramolecular assembly strategies to create peptide-protein composite hydrogels with predictable shape-to-function features

Purely protein-based hydrogels are widely used in tissue engineering for their biomimicry and biocompatibility, yet remain challenging to tailor with precision and predictability at biological and mechanical levels. To overcome this, synthetic self-assembling peptide amphiphiles (PAs) offer opportunities for supramolecular customization, both as single-phase materials and co-assembled with proteins to create hybrid nanocomposites with emerging functionalities. Similarly, contactless, sound-guided bioassembly techniques using liquid-phase hydrogel precursors are emerging as strategic tools for obtaining structured and functional hydrogels. Leveraging these advances, here a fast, contactless, one-pot bioassembly strategy merging supramolecular PA self-assembly with sound-guided patterning to fabricate hybrid peptide-protein hydrogels with programmable shape-to-function features is presented. Using fibrin as proof-of-concept, material performance is biologically enhanced by incorporating growth factor-binding PAs, while inorganic microparticles are embedded and spatially organized via acoustic fields to tune mechanical properties. This strategy allows predictable tuning of composite stiffness and architecture by adjusting sound wave frequency, with acoustic fields guiding material organization from micro-to-macroscale. Composite hydrogels result highly permissive to cell infiltration in vitro and versatile platform to tune immune cell-material interactions. This modular biofabrication platform integrating supramolecular and sound-guided processes can be generalized to other building blocks opening unique opportunities for scalable, tunable, and hierarchically-organized biomaterials.

bioengineering↗

Bioactive coatings on 3D printed polycaprolactone scaffolds for bone regeneration: a novel murine femur defect model for examination of the biomaterial capacity for repair.

Bone tissue engineering is a rapidly advancing field that seeks to develop efficacious approaches for treating non-healing fractures and large bone defects. Healing complications arise due to trauma, disease, infection, aseptic loosening of orthopaedic implants or iatrogenic causes. An ideal biodegradable scaffold would induce and support bone formation until the bone matrix is sufficiently stable to facilitate healing. The current study has examined bone augmentation, using functionalised coated scaffolds, with the hypothesised potential to induce skeletal cell differentiation for the repair of critical-sized bone defects. However, challenges in clinical translation arise from the alterations in cellular microenvironment that are present in the translation from in vitro to in vivo with the application of animal models of progressively increasing size and complexity of the implantation site. 3D printed, porous poly(caprolactone) trimethacrylate (denoted PCL-TMA900) scaffolds were applied within a murine femur defect, stabilised by a polyimide intramedullary pin, to assess the efficacy of select coatings in inducing bone formation. The PCL-TMA900 scaffolds were coated with i) elastin-like polypeptide (ELP), ii) poly(ethyl acrylate)/fibronectin/bone morphogenetic protein-2 (PEA/FN/BMP-2), iii) both ELP and PEA/FN/BMP-2 concurrently, or iv) Laponite nanoclay binding BMP-2, as bioactive coatings. The murine femur defect model was refined to assess the coated PCL-TMA900 scaffolds in an osseous defect, with sequential microcomputed tomography ({micro}CT) and histological analysis of the new bone tissue. Overall, PCL-TMA900 was found to be an optimal robust, biocompatible, 3D printable scaffold material. All PCL-TMA900 scaffolds, uncoated and coated, showed integration with the femur. The PCL-TMA900 scaffold coated with the nanoclay material Laponite and BMP-2 induced consistent, significant bone formation compared to the uncoated PCL-TMA900 scaffold. Bone formation was observed within the pores of the Laponite/BMP-2 coated scaffold. Critically, no heterotopic bone formation was observed as the BMP-2 was retained around the scaffold and not released into the tissues, producing bone around the scaffold in the desired shape and volume, compared to bone formation observed with the positive control (collagen sponge/BMP-2 construct). In comparison, the ELP coated and PEA/FN/BMP-2 scaffolds did not demonstrate significant or consistent bone formation compared to uncoated PCL-TMA900 control scaffolds. In summary, nanoclay Laponite/BMP-2 coated PCL-TMA900 scaffolds offer a biodegradable, osteogenic construct for bone augmentation with potential for development into a large scale polymer scaffold for translation to the clinic.

bioengineering↗

Bioactive coatings on 3D printed scaffolds for bone regeneration: Translation from in vitro to in vivo models and the impact of material properties and growth factor concentration.

Bone tissue engineering is a rapidly advancing field that seeks to develop new functional bone tissue, harnessing materials for application in bone defects which may fail to heal without intervention, as seen in critical-sized bone defects. The material properties must be developed, tailored and optimised as the environment progresses, through increasing animal size and complexity, of the target bone defect site. This study has examined the potential of a poly(caprolactone) trimethacrylate (PCL-TMA) 3D-printable scaffold with select bioactive coatings to function as a scaffold to augment bone formation. Three bioactive coatings were examined, i) elastin-like protein (ELP), ii) poly (ethyl acrylate) (PEA), fibronectin (FN) and bone morphogenetic protein-2 (BMP-2) applied sequentially (PEA/FN/BMP-2) and iii) both ELP and PEA/FN/BMP-2 coatings applied concurrently. The PCL-TMA scaffold construct was observed to be a robust scaffold material and the bioactive coatings applied were found to be biocompatible, with a significant osteogenic response from human skeletal cell populations observed in vitro. The PCL-TMA scaffold and bioactive coatings supported angiogenesis and displayed excellent biocompatibility following evaluation on the chorioallantoic membrane (CAM) assay. Biocompatibility was confirmed, however, no significant bone formation was detected, following examination of heterotopic bone formation in the murine subcutaneous implantation model, whereas extensive mineralisation was observed in the positive control material of collagen sponge with BMP-2. The absence of bone formation on the PCL-TMA scaffolds, in vivo, was potentially a consequence of the method of action of the applied coatings, the surface area of the scaffold construct for BMP-2 binding and the necessity of an appropriate in vivo environment to facilitate skeletal cell ingress, warranting future examination in an orthotopic bone defect model of bone tissue repair. The current studies demonstrate the development of a range of innovative scaffold constructs with in vitro efficacy and clearly illustrate the importance of an appropriate in vivo environment to validate in vitro functionality prior to scale up and preclinical application.

bioengineering↗

Gut microbiome diversity detected by high-coverage 16S and shotgun sequencing of matched stool and colon biopsy samples

The gut microbiome has a fundamental role in human health and disease. However, studying the complex structure and function of the gut microbiome using next generation sequencing is challenging and prone to reproducibility problems due to the heterogeneity of sample sets. Here, we obtained cross-sectional colon biopsies and faecal samples from nine participants in our COLSCREEN study and sequenced them in high coverage using Illumina pair-end shotgun (for faecal samples) and IonTorrent 16S (for paired feces and colon biopsies) technologies. The metagenomes consisted of between 47 and 92 million reads per sample and the targeted sequencing covered more than 300K reads per sample across seven hypervariable regions of the 16S gene. Our data is freely available and coupled with code for the presented metagenomic analysis using up-to-date bioinformatics algorithms. These results will add up to the informed insights into designing comprehensive microbiome analysis and also provide data for further testing for unambiguous gut microbiome analysis.

bioinformatics↗