Making microenvironments: A look into incorporating macromolecular crowding into in vitro experiments, to generate biomimetic microenvironments which are capable of directing cell function for tissue engineering applications

Abstract

Biomimetic microenvironments are key components to successful cell culture and tissue engineering in vitro. One of the most accurate biomimetic microenvironments is that made by the cells themselves. Cell-made microenvironments are most similar to the in vivo state as they are cell-specific and produced by the actual cells which reside in that specific microenvironment. However, cell-made microenvironments have been challenging to re-create in vitro due to the lack of extracellular matrix composition, volume and complexity which are required. By applying macromolecular crowding to current cell culture protocols, cell-made microenvironments, or cell-derived matrices, can be generated at significant rates in vitro. In this review, we will examine the causes and effects of macromolecular crowding and how it has been applied in several in vitro systems including tissue engineering.

Intrinsic Regulatory Role of RNA Structural Arrangement in Alternative Splicing Control

“…Cellular environment is characterized by molecular crowding underlain by a heterogeneous composition of inorganic components (e.g., cations, anions) and organic molecules (e.g., NTPs, RNA, proteins) of defined sizes and charge which entrain a steric hindrance due to their high accumulation and impenetrability [ 82 , 83 ]. This issue and its impact on macromolecules and biological processes have been covered in several excellent reviews [ 83 , 84 , 85 ]. What intrigues us, is that the molecular crowding vastly contributes to the stability of RNA structure and the kinetics of RNA folding by limiting RNA spatially [ 86 , 87 ].…”

A high content, phenotypic ‘scar-in-a-jar’ assay for rapid quantification of collagen fibrillogenesis using disease-derived pulmonary fibroblasts

“…Indeed, this assay is not limited to IPF research. The benefits of macromolecular crowding in tissue-specific cultures have been described for a number of other fibrotic and tissue remodelling assays [40] including using corneal fibroblasts [36], dermal fibroblasts [41] and bone marrow stroma-derived cells [42] affecting ECM deposition as well as modifying the cellular phenotype [43]. Furthermore, this assay could be developed to explore the impact of ECM deposition in complex multi-cellular systems.…”

Engineering Cell‐Derived Matrices: From 3D Models to Advanced Personalized Therapies

“…Furthermore, it affects the nature of all the species involved, such as reactivity rates, enzyme kinetics, metabolon stabilization, diffusion of molecules, oligomerization, microcompartmentalization, protein conformation and aggregation, as well as interactions with the environment affecting pH, ion concentrations, and ionic strength. [82,84] It also influences cell signaling and gene expression by limiting diffusion, with many of these changes in the order of magnitudes. [81] MMC can regulate ECM features in two ways: first, by modifying cell behavior and ECM expression and, second, by modifying the cell media during ECM synthesis.…”