Designed Surface Topographies Control ICAM-1 Expression in Tonsil-Derived Human Stromal Cells

Abstract

Fibroblastic reticular cells (FRCs), the T-cell zone stromal cell subtype in the lymph nodes, create a scaffold for adhesion and migration of immune cells, thus allowing them to communicate. Although known to be important for the initiation of immune responses, studies about FRCs and their interactions have been impeded because FRCs are limited in availability and lose their function upon culture expansion. To circumvent these limitations, stromal cell precursors can be mechanotranduced to form mature FRCs. Here, we used a library of designed surface topographies to trigger FRC differentiation from tonsil-derived stromal cells (TSCs). Undifferentiated TSCs were seeded on a TopoChip containing 2176 different topographies in culture medium without differentiation factors, then monitored cell morphology and the levels of ICAM-1, a marker of FRC differentiation. We identified 112 and 72 surfaces that upregulated and downregulated, respectively, ICAM-1 expression. By monitoring cell morphology, and expression of the FRC differentiation marker ICAM-1 via image analysis and machine learning, we discovered correlations between ICAM-1 expression, cell shape and design of surface topographies and confirmed our findings by using flow cytometry. Our findings confirmed that TSCs are mechano-responsive cells and identified particular topographies that can be used to improve FRC differentiation protocols.

Immune Modulation by Design: Using Topography to Control Human Monocyte Attachment and Macrophage Differentiation

“…[28] We employed the TopoChip technology platform which allows 2176 unique, mathematically defined surface topographies to be screened on each chip in duplicate for their influence on cell response in a high throughput manner. [29][30][31][32][33] Using algorithms to build topographical features from primitive features (circle, triangle, and rectangle; sized 3-23 µm in diameter and 10 µm in height), 2176 designs were arranged periodically to form 290 × 290 µm TopoUnits. Here, we present the first report of an unbiased screen to investigate how this diverse library of topographies influences human macrophage attachment and phenotype.…”

From Shape to Function: The Next Step in Bioprinting

“…High‐accuracy and multimaterial printing can permit the generation of models with increasing degree of complexity, in which different combinations of geometrical cues, physicochemical properties and relative positioning of cells and materials can be combined. In order to achieve this, the influence of each variable should be isolated and studied, possibly even converging the field of biofabrication with automated high‐throughput analysis, materiomics, and artificial intelligence‐driven approaches that are already being introduced for biomaterial research . Such systematic research will provide key insights for the design of the next generation of bioprinted constructs, eventually clearing an important step toward clinical translation.…”

“…In order to achieve this, the influence of each variable should be isolated and studied, possibly even converging the field of biofabrication with automated high-throughput analysis, materiomics, and artificial intelligence-driven approaches that are already being introduced for biomaterial research. [ 295 – 297 ] Such systematic research will provide key insights for the design of the next generation of bioprinted constructs, eventually clearing an important step toward clinical translation. Additionally, although most of the expectations of bioprinting are associated with the generation of constructs that can copy or simulate the function of human tissues, alternative nonphysiological elements derived from other disciplines in biology, physics and engineering could also be envisioned and introduced, as recently suggested with the bioprinting of stimuli-responsive materials, nonmammalian cells as sources of metabolites or constructs designed by deterministic chaos principles as platforms to study cell–cell interactions.…”

High-Throughput Methods in the Discovery and Study of Biomaterials and Materiobiology

“… 455 Cells seeded on the TopoChip and screened with HCI methods enabled discovery of the topographies that, for example, promote osteogenesis, 566 form biomechanical niche, 567 or control ICAM-1 expression. 897 …”