Tailoring metabolic activity assays for tumour-engineered 3D models.

Monitoring cell behaviour in hydrogel-based 3D models is critical for assessing their growth and response to cytotoxic treatment. Resazurin-based PrestoBlue and AlamarBlue reagents are frequently used metabolic activity assays when determining cell responses. However, both assays are largely applied to cell monolayer cultures but yet to have a defined protocol for use in hydrogel-based 3D models.

Nano- and Microstructures of Collagen-Nanocellulose Hydrogels as Engineered Extracellular Matrices.

The extracellular matrix (ECM) is the fundamental acellular element of human tissues, providing their mechanical structure while delivering biomechanical and biochemical signals to cells. Three-dimensional (3D) tissue models commonly use hydrogels to recreate the ECM and support the growth of cells as organoids and spheroids. Collagen-nanocellulose (COL-NC) hydrogels rely on the blending of both polymers to design matrices with tailorable physical properties.

3D Collagen-Nanocellulose Matrices Model the Tumour Microenvironment of Pancreatic Cancer.

Three-dimensional (3D) cancer models are invaluable tools designed to study tumour biology and new treatments. Pancreatic ductal adenocarcinoma (PDAC), one of the deadliest types of cancer, has been progressively explored with bioengineered 3D approaches by deconstructing elements of its tumour microenvironment. Here, we investigated the suitability of collagen-nanocellulose hydrogels to mimic the extracellular matrix of PDAC and to promote the formation of tumour spheroids and multicellular 3D cultures with stromal cells.

A thermo-responsive collagen-nanocellulose hydrogel for the growth of intestinal organoids.

Three-dimensional (3D) cell culture systems include bioengineered microenvironments that mimic the complexity of human tissues and organs in vitro. Robust biological models, like organoids and spheroids, rely on biomaterials to emulate the biochemical and biomechanical properties found in the extracellular matrix (ECM). Collagen (COL) is the main protein component of the ECM and has been used to generate fibrous matrices for 3D cell culture.

Perspective on Constructing Cellulose-Hydrogel-Based Gut-Like Bioreactors for Growth and Delivery of Multiple-Strain Probiotic Bacteria.

The current perspective presents an outlook on developing gut-like bioreactors with immobilized probiotic bacteria using cellulose hydrogels. The innovative concept of using hydrogels to simulate the human gut environment by generating and maintaining pH and oxygen gradients in the gut-like bioreactors is discussed. Fundamentally, this approach presents novel methods of production as well as delivery of multiple strains of probiotics using bioreactors.

Engineered Plant-Based Nanocellulose Hydrogel for Small Intestinal Organoid Growth.

Organoids are three-dimensional self-renewing and organizing clusters of cells that recapitulate the behavior and functionality of developed organs. Referred to as "organs in a dish," organoids are invaluable biological models for disease modeling or drug screening. Currently, organoid culture commonly relies on an expensive and undefined tumor-derived reconstituted basal membrane which hinders its application in high-throughput screening, regenerative medicine, and diagnostics.

Cationic Cross-Linked Nanocellulose-Based Matrices for the Growth and Recovery of Intestinal Organoids.

Highly carboxylated nanocellulose fibers can be functionalized with cell adhesive peptides and cationic cross-linked to form matrices for a three-dimensional (3D) cell culture. It is hypothesized that nanocellulose hydrogels cross-linked with divalent cations can provide the required biochemical and mechanical properties for intestinal organoid growth and recovery. Nanocellulose hydrogels are produced by TEMPO- and TEMPO-periodate-mediated oxidation and functionalized with RGD peptides.

Rapid Gel Card Agglutination Assays for Serological Analysis Following SARS-CoV-2 Infection in Humans.

High-throughput and rapid serology assays to detect the antibody response specific to severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) in human blood samples are urgently required to improve our understanding of the effects of COVID-19 across the world. Short-term applications include rapid case identification and contact tracing to limit viral spread, while population screening to determine the extent of viral infection across communities is a longer-term need. Assays developed to address these needs should match the ASSURED criteria.

Photothermal incubation of red blood cells by laser for rapid pre-transfusion blood group typing.

Safe blood transfusion requires compatibility testing of donor and recipient to prevent potentially fatal transfusion reactions. Detection of immunoglobulin G (IgG) antibodies requires incubation at 37 °C, often for up to 15 minutes. Current incubation technology predominantly relies on slow thermal-gradient dependent conduction.

Nanocellulose Hydrogel for Blood Typing Tests.

The gel test is the most prevalent method for the forward and reverse blood typing tests. It relies on the controlled centrifugation of red blood cells (RBCs) and antibodies through a gel column. This noncontinuous matrix is currently based on microbeads that often lack sensitivity.

Engineering nanocellulose hydrogels for biomedical applications.

Nanocellulose hydrogels are highly hydrated porous cellulosic soft materials with good mechanical properties. These cellulose-based gels can be produced from bacterial or plant cellulose nanofibrils, which are hydrophilic, renewable, biodegradable and biocompatible. Nanocellulose, whether fibrils (CNF), crystals (CNC) or bacterial (BNC), has a high aspect ratio and surface area, and can be chemically modified with functional groups or by grafting biomolecules.