Plant-derived human recombinant growth factors and serum albumin maintain stemness of human-induced pluripotent stem cells

The Investigation of the Subtle Structural Discrepancies between Oryza Sativa Recombinant and Plasma-Derived Human Serum Albumins to Design a Novel Nanoparticle as a Taxane Delivery System

To solve the large size faultiness of Oryza sativa recombinant human serum albumin nanoparticle (OsrHSA NP), the structural discrepancies between OsrHSA and plasma-derived human serum albumin (pdHSA) were analyzed deeply in this research. It demonstrated that there were some subtle structural discrepancies located in subdomain IA and IIA between OsrHSA and pdHSA, which included peptide backbone, disulphide bridge and some amino acids. Firstly, the structural discrepancies were investigated through literature comparison, it inferred that the structural discrepancies resulted from the fatty acid (FA) binding to OsrHSA at site 2 of subdomain IA and IIA. To form a cavity for accommodation of FA molecule in OsrHSA, the peptide backbone structure of subdomain IA and IIA would change, accompanied by the conformational transition of disulphide bridges and side chain structure change of some amino acids in subdomain IA and IIA. These alterations induced the exposure of tryptophan (Trp) and tyrosine (Tyr) residues in subdomain IA and IIA and the decrease of net negative charges of molecular surface. The former would promote more OsrHSA molecules aggregate, and the latter would weaken the electrostatic repulsion. As a result, the size of OsrHSA NP was more extensive than that of pdHSA NP (175.84 ± 15.63 nm vs. 31.67 ± 1.31 nm) when the concentration of Dimethyl Sulphoxide (DMSO) was 30% (v/v). In this study, the experimental scheme of OsrHSA NP preparation was improved. There were two changes in the enhanced preparation scheme: pH 8.2 PBS buffer and 63% DMSO. It indicated that the improved OsrHSA NP carrier was comparable to the pdHSA NP carrier. The size and drug loading of paclitaxel-loaded improved OsrHSA NP were 53.57 ± 3.63 nm and 7.25 ± 0.46% (w/w), and those of docetaxel-loaded improved OsrHSA NP were 44.75 ± 2.26 nm and 8.43 ± 0.74% (w/w). Moreover, both NPs exhibited good stability for 168 h at 7.4 pH values. It is established that the improved OsrHSA NP is comparable to the pdHSA NP as a taxane delivery system.

Albumin as a Biomaterial and Therapeutic Agent in Regenerative Medicine

Albumin is a constitutional plasma protein, with well-known biological functions, e.g., a nutrient for stem cells in culture. However, albumin is underutilized as a biomaterial in regenerative medicine. This review summarizes the advanced therapeutic uses of albumin, focusing on novel compositions that take advantage of the excellent regenerative potential of this protein. Albumin coating can be used for enhancing the biocompatibility of various types of implants, such as bone grafts or sutures. Albumin is mainly known as an anti-attachment protein; however, using it on implantable surfaces is just the opposite: it enhances stem cell adhesion and proliferation. The anticoagulant, antimicrobial and anti-inflammatory properties of albumin allow fine-tuning of the biological reaction to implantable tissue-engineering constructs. Another potential use is combining albumin with natural or synthetic materials that results in novel composites suitable for cardiac, neural, hard and soft tissue engineering. Recent advances in materials have made it possible to electrospin the globular albumin protein, opening up new possibilities for albumin-based scaffolds for cell therapy. Several described technologies have already entered the clinical phase, making good use of the excellent biological, but also regulatory, manufacturing and clinical features of serum albumin.

An Edible, Decellularized Plant Derived Cell Carrier for Lab Grown Meat

Rapidly expanding skeletal muscle satellite cells with cost-effective methods have been presented as a solution for meeting the growing global demand for meat. A common strategy for scaling cell proliferation employs microcarriers, small beads designed to support anchorage-dependent cells in suspension-style bioreactors. No carrier has yet been marketed for the cultivation of lab-grown meat. The objective of this study was to demonstrate a rapid, food safe, decellularization procedure to yield cell-free extracellular matrix scaffolds and evaluate them as cell carriers for lab grown meat. Broccoli florets were soaked in SDS, Tween-20, and bleach for 48 h. The decellularization process was confirmed via histology, which showed an absence of cell nuclei, and DNA quantification (0.0037 ± 0.00961 μg DNA/mg tissue). Decellularized carriers were sorted by cross sectional area (7.07 ± 1.74 mm2, 3.03 ± 1.15 mm2, and 0.49 ± 0.3 mm2) measured for eccentricity (0.73 ± 0.16). Density measurements of decellularized carriers (1.01 ± 0.01 g/cm) were comparable to traditional microcarriers. Primary bovine satellite cells were inoculated into and cultured within a reactor containing decellularized carriers. Cell adhesion was observed and cell death was limited to 2.55 ± 1.09%. These studies suggested that broccoli florets may serve as adequate edible carrier scaffolds for satellite cells.