A reconfigurable microscale assay enables insights into cancer-associated fibroblast modulation of immune cell recruitment.

Innate immune cell infiltration into neoplastic tissue is the first line of defense against cancer and can play a deterministic role in tumor progression. Here, we describe a series of assays, using a reconfigurable microscale assay platform (i.e.

Reconfigurable open microfluidics for studying the spatiotemporal dynamics of paracrine signalling.

The study of intercellular signalling networks requires organotypic microscale systems that facilitate the culture, conditioning and manipulation of cells. Here, we describe a reconfigurable microfluidic cell-culture system that facilitates the assembly of three-dimensional tissue models by stacking layers that contain preconditioned microenvironments. By using principles of open and suspended microfluidics, the Stacks system is easily assembled or disassembled to provide spatial and temporal manoeuvrability in two-dimensional and three-dimensional assays of multiple cell types, enabling the modelling of sequential paracrine-signalling events, such as tumour-cell-mediated differentiation of macrophages and macrophage-facilitated angiogenesis.

Interaction with an endothelial lumen increases neutrophil lifetime and motility in response to .

Neutrophil infiltration into tissues is essential for host defense and pathogen clearance. Although many of the signaling pathways involved in the transendothelial migration of neutrophils are known, the role of the endothelium in regulating neutrophil behavior in response to infection within interstitial tissues remains unclear. Here we developed a microscale 3-dimensional (3D) model that incorporates an endothelial lumen, a 3D extracellular matrix, and an intact bacterial source to model the host microenvironment.

An Accessible Organotypic Microvessel Model Using iPSC-Derived Endothelium.

While organotypic approaches promise increased relevance through the inclusion of increased complexity (e.g., 3D extracellular microenvironment, structure/function relationships, presence of multiple cell types), cell source is often overlooked.

Selective Photomechanical Detachment and Retrieval of Divided Sister Cells from Enclosed Microfluidics for Downstream Analyses.

Considerable evidence suggests that self-renewal and differentiation of cancer stem-like cells, a key cell population in tumorgenesis, can determine the outcome of disease. Though the development of microfluidics has enhanced the study of cellular lineage, it remains challenging to retrieve sister cells separately inside enclosed microfluidics for further analyses. In this work, we developed a photomechanical method to selectively detach and reliably retrieve target cells from enclosed microfluidic chambers.

Single cell dual adherent-suspension co-culture micro-environment for studying tumor-stromal interactions with functionally selected cancer stem-like cells.

Considerable evidence suggests that cancer stem-like cells (CSCs) are critical in tumor pathogenesis, but their rarity and transience has led to much controversy about their exact nature. Although CSCs can be functionally identified using dish-based tumorsphere assays, it is difficult to handle and monitor single cells in dish-based approaches; single cell-based microfluidic approaches offer better control and reliable single cell derived sphere formation. However, like normal stem cells, CSCs are heavily regulated by their microenvironment, requiring tumor-stromal interactions for tumorigenic and proliferative behaviors.

High-Throughput Single-Cell Derived Sphere Formation for Cancer Stem-Like Cell Identification and Analysis.

Considerable evidence suggests that many malignancies are driven by a cellular compartment that displays stem cell properties. Cancer stem-like cells (CSCs) can be identified by expression of cell surface markers or enzymatic activity, but these methods are limited by phenotypic heterogeneity and plasticity of CSCs. An alternative phenotypic methodology based on in-vitro sphere formation has been developed, but it is typically labor-intensive and low-throughput.

Identifying an ovarian cancer cell hierarchy regulated by bone morphogenetic protein 2.

Whether human cancer follows a hierarchical or stochastic model of differentiation is controversial. Furthermore, the factors that regulate cancer stem-like cell (CSC) differentiation potential are largely unknown. We used a novel microfluidic single-cell culture method to directly observe the differentiation capacity of four heterogeneous ovarian cancer cell populations defined by the expression of the CSC markers aldehyde dehydrogenase (ALDH) and CD133.

Single-cell Migration Chip for Chemotaxis-based Microfluidic Selection of Heterogeneous Cell Populations.

Tumor cell migration toward and intravasation into capillaries is an early and key event in cancer metastasis, yet not all cancer cells are imbued with the same capability to do so. This heterogeneity within a tumor is a fundamental property of cancer. Tools to help us understand what molecular characteristics allow a certain subpopulation of cells to spread from the primary tumor are thus critical for overcoming metastasis.

Traceable clonal culture and chemodrug assay of heterogeneous prostate carcinoma PC3 cells in microfluidic single cell array chips.

Cancer heterogeneity has received considerable attention for its role in tumor initiation and progression, and its implication for diagnostics and therapeutics in the clinic. To facilitate a cellular heterogeneity study in a low cost and highly efficient manner, we present a microfluidic platform that allows traceable clonal culture and characterization. The platform captures single cells into a microwell array and cultures them for clonal expansion, subsequently allowing on-chip characterization of clonal phenotype and response against drug treatments.

Paired single cell co-culture microenvironments isolated by two-phase flow with continuous nutrient renewal.

Cancer-stromal cell interactions are a critical process in tumorigenesis. Conventional dish-based assays, which simply mix two cell types, have limitations in three aspects: 1) limited control of the cell microenvironment; 2) inability to study cell behavior in a single-cell manner; and 3) have difficulties in characterizing single cell behavior within a highly heterogeneous cell population (e.g.