Antibodies have become a well-established tool in the fields of diagnostics and treatments, especially within oncology, immunology, and infectious diseases. Despite their effectiveness, antibodies are limited by their size, high production costs, and immunogenicity, which in the long run can lead to significant challenges in the medical field. Some well-researched options to antibodies are non-antibody proteins and peptide scaffolds. In this report, focus lies on providing an overview of designed ankyrin repeat proteins (DARPins), Ankyrons, Affibodies, Anticalins, Adnectins and bicyclic peptides, all different formats of non-antibody proteins and peptide scaffolds. Ranging from 1-20 kDa, these non-antibodies feature stable structural elements and modifiable regions for highly specific bonds with high affinity. While originating from natural sources, non-antibodies can be produced synthetically at a low cost, while also decreasing immunogenicity. This report presents the structures of the chosen six formats, and also their function in various applications, as well as their potential to overcome the hurdles of regular antibodies. With the increasing risks of emerging diseases and other health-related issues, non-antibody proteins and peptide scaffolds show great potential for replacing or assisting conventional antibodies in healthcare and biomedical research.

Acute Lymphoblastic Leukemia (ALL) is one of the most common type of hematologic malignancy in children, characterized by an excessive proliferation of unfunctional immature lymphoblasts in the blood and the bone marrow, which leads to a range of severe blood-related complications. Given the remarkable increase in the prevalence of leukemia in the past 20 years, there has been a particular interest in the development of in vitro experimental models for cancer research. Ultra-short self-assembling peptides have shown to be a promising class of synthetic biomaterials due to their biocompatibility, tunable mechanical properties, and the possibility of controlling the scaffold composition. The objective of this study was to create a bioactive but well-defined synthetic 3D model of the bone marrow (BM) microenvironment for the simulation of ALL using biofunctionalized ultrashort self-assembling peptide scaffolds. Different bioactive motifs derived from integral extracellular matrix (ECM) constituents that are known to enhance cell-matrix adhesion, including RGDS from fibronectin, YIGSR from laminin, and GFOGER from collagen, were incorporated into the parent peptide IIZK. These peptides demonstrated to be capable of generating stable hydrogel structures composed of fibrous porous networks, each with unique nanofiber morphology and mechanical properties. All the peptide scaffolds that were investigated in this study exhibited optimal characteristics concerning the cytocompatibility of multiple BM niche cells, including human bone marrow mesenchymal stem cells (MSCs), human umbilical vein endothelial cells (HUVECs), and patient derived ALL cells. The suitability of the scaffolds as drug screening platforms was evaluated, demonstrating their potential as versatile tools for the assessment of drug efficacy.

No description available.