Computational model and microfluidic platform for the investigation of paracrine and autocrine signaling in mouse embryonic stem cells

Fluid flow-induced modulation of viability and osteodifferentiation of periodontal ligament stem cell spheroids-on-chip

Developing physiologically relevant in vitro models for studying periodontitis is crucial for understanding its pathogenesis and developing effective therapeutic strategies. In this study, we aimed to integrate the spheroid culture of periodontal ligament stem cells (PDLSCs) within a spheroid-on-chip microfluidic perfusion platform and to investigate the influence of interstitial fluid flow on morphogenesis, cellular viability, and osteogenic differentiation of PDLSC spheroids. PDLSC spheroids were seeded onto the spheroid-on-chip microfluidic device and cultured under static and flow conditions. Computational analysis demonstrated the translation of fluid flow rates of 1.2 μl min-1 (low-flow) and 7.2 μl min-1 (high-flow) to maximum fluid shear stress of 59 μPa and 360 μPa for low and high-flow conditions, respectively. The spheroid-on-chip microfluidic perfusion platform allowed for modulation of flow conditions leading to larger PDLSC spheroids with improved cellular viability under flow compared to static conditions. Modulation of fluid flow enhanced the osteodifferentiation potential of PDLSC spheroids, demonstrated by significantly enhanced alizarin red staining and alkaline phosphatase expression. Additionally, flow conditions, especially high-flow conditions, exhibited extensive calcium staining across both peripheral and central regions of the spheroids, in contrast to the predominantly peripheral staining observed under static conditions. These findings highlight the importance of fluid flow in shaping the morphological and functional properties of PDLSC spheroids. This work paves the way for future investigations exploring the interactions between PDLSC spheroids, microbial pathogens, and biomaterials within a controlled fluidic environment, offering insights for the development of innovative periodontal therapies, tissue engineering strategies, and regenerative approaches.

Guiding Hepatic Differentiation of Pluripotent Stem Cells Using 3D Microfluidic Co-Cultures with Human Hepatocytes

Human pluripotent stem cells (hPSCs) are capable of unlimited proliferation and can undergo differentiation to give rise to cells and tissues of the three primary germ layers. While directing lineage selection of hPSCs has been an active area of research, improving the efficiency of differentiation remains an important objective. In this study, we describe a two-compartment microfluidic device for co-cultivation of adult human hepatocytes and stem cells. Both cell types were cultured in a 3D or spheroid format. Adult hepatocytes remained highly functional in the microfluidic device over the course of 4 weeks and served as a source of instructive paracrine cues to drive hepatic differentiation of stem cells cultured in the neighboring compartment. The differentiation of stem cells was more pronounced in microfluidic co-cultures compared to a standard hepatic differentiation protocol. In addition to improving stem cell differentiation outcomes, the microfluidic co-culture system described here may be used for parsing signals and mechanisms controlling hepatic cell fate.

Autocrine TGF-β in Cancer: Review of the Literature and Caveats in Experimental Analysis

Autocrine signaling is defined as the production and secretion of an extracellular mediator by a cell followed by the binding of that mediator to receptors on the same cell to initiate signaling. Autocrine stimulation often operates in autocrine loops, a type of interaction, in which a cell produces a mediator, for which it has receptors, that upon activation promotes expression of the same mediator, allowing the cell to repeatedly autostimulate itself (positive feedback) or balance its expression via regulation of a second factor that provides negative feedback. Autocrine signaling loops with positive or negative feedback are an important feature in cancer, where they enable context-dependent cell signaling in the regulation of growth, survival, and cell motility. A growth factor that is intimately involved in tumor development and progression and often produced by the cancer cells in an autocrine manner is transforming growth factor-β (TGF-β). This review surveys the many observations of autocrine TGF-β signaling in tumor biology, including data from cell culture and animal models as well as from patients. We also provide the reader with a critical discussion on the various experimental approaches employed to identify and prove the involvement of autocrine TGF-β in a given cellular response.

Development of a microfluidic approach for the real-time analysis of extrinsic TGF-β signalling

Autocrine and paracrine signalling are traditionally difficult to study due to the sub-micromolar concentrations involved. This has proven to be especially limiting in the study of embryonic stem cells that rely on such signalling for viability, self-renewal, and proliferation. Microfluidics allows to achieve local concentrations of ligands representative of the in vivo stem cell niche, gaining more precise control over the cell microenvironment, as well as to manipulate ligands availability with high temporal resolution and minimal amount of reagents. Here we developed a microfluidics-based system for monitoring the dynamics of TGF-β pathway activity by means of a SMAD2/3-dependent luciferase reporter. We first validated our system by showing dose-dependent transcriptional activation. We then tested the effects of pulsatile stimulation and delayed inhibition of TGF-β activity on signalling dynamics. Finally, we show that our microfluidic system, unlike conventional culture systems, can detect TGF-β ligands secreted in the conditioned medium from hESCs.

Exploring microfluidics as a tool to evaluate the biological properties of a titanium alloy under dynamic conditions

When evaluating the biological properties of titanium under dynamic conditions, cell proliferation was shown to be dominant over cell differentiation.

Shaping Cell Fate: Influence of Topographical Substratum Properties on Embryonic Stem Cells

Development of multicellular organisms is a highly orchestrated process, with cells responding to factors and features present in the extracellular milieu. Changes in the surrounding environment help decide the fate of cells at various stages of development. This review highlights recent research that details the effects of mechanical properties of the surrounding environment and extracellular matrix and the underlying molecular mechanisms that regulate the behavior of embryonic stem cells (ESCs). In this study, we review the role of mechanical properties during embryogenesis and discuss the effect of engineered microtopographies on ESC pluripotency.

Mathematical Models of Pluripotent Stem Cells: At the Dawn of Predictive Regenerative Medicine

Regenerative medicine, ranging from stem cell therapy to organ regeneration, is promising to revolutionize treatments of diseases and aging. These approaches require a perfect understanding of cell reprogramming and differentiation. Predictive modeling of cellular systems has the potential to provide insights about the dynamics of cellular processes, and guide their control. Moreover in many cases, it provides alternative to experimental tests, difficult to perform for practical or ethical reasons. The variety and accuracy of biological processes represented in mathematical models grew in-line with the discovery of underlying molecular mechanisms. High-throughput data generation led to the development of models based on data analysis, as an alternative to more established modeling based on prior mechanistic knowledge. In this chapter, we give an overview of existing mathematical models of pluripotency and cell fate, to illustrate the variety of methods and questions. We conclude that current approaches are yet to overcome a number of limitations: Most of the computational models have so far focused solely on understanding the regulation of pluripotency, and the differentiation of selected cell lineages. In addition, models generally interrogate only a few biological processes. However, a better understanding of the reprogramming process leading to ESCs and iPSCs is required to improve stem-cell therapies. One also needs to understand the links between signaling, metabolism, regulation of gene expression, and the epigenetics machinery.

Three-dimensional models for studying development and disease: moving on from organisms to organs-on-a-chip and organoids

Human development and disease are challenging to study because of lack of experimental accessibility to in vivo systems and the complex nature of biological processes. For these reasons researchers turn to the use of model systems, ranging in complexity and scale from single cells to model organisms. While the use of model organisms is valuable for studying physiology and pathophysiology in an in vivo context and for aiding pre-clinical development of therapeutics, animal models are costly, difficult to interrogate, and not always equivalent to human biology. For these reasons, three-dimensional (3D) cell cultures have emerged as an attractive model system that contains key aspects of in vivo tissue and organ complexity while being more experimentally tractable than model organisms. In particular, organ-on-a-chip and organoid models represent orthogonal approaches that have been able to recapitulate characteristics of physiology and disease. Here, we review advances in these two categories of 3D cultures and applications in studying development and disease. Additionally, we discuss development of key technologies that facilitate the generation of 3D cultures, including microfluidics, biomaterials, genome editing, and imaging technologies.

Microfluidic platforms for the investigation of intercellular signalling mechanisms

Intercellular signalling has been identified as a highly complex process, responsible for orchestrating many physiological functions. While conventional methods of investigation have been useful, their limitations are impeding further development. Microfluidics offers an opportunity to overcome some of these limitations. Most notably, microfluidic systems can emulate the in-vivo environments. Further, they enable exceptionally precise control of the microenvironment, allowing complex mechanisms to be selectively isolated and studied in detail. There has thus been a growing adoption of microfluidic platforms for investigation of cell signalling mechanisms. This review provides an overview of the different signalling mechanisms and discusses the methods used to study them, with a focus on the microfluidic devices developed for this purpose.

Maintenance and neuronal cell differentiation of neural stem cells C17.2 correlated to medium availability sets design criteria in microfluidic systems

BACKGROUND

Neural stem cells (NSCs) play an important role in developing potential cell-based therapeutics for neurodegenerative disease. Microfluidics has proven a powerful tool in mechanistic studies of NSC differentiation. However, NSCs are prone to differentiate when the nutrients are limited, which occurs unfavorable by fast medium consumption in miniaturized culture environment. For mechanistic studies of NSCs in microfluidics, it is vital that neuronal cell differentiation is triggered by controlled factors only. Thus, we studied the correlation between available cell medium and spontaneous neuronal cell differentiation of C17.2 NSCs in standard culture medium, and proposed the necessary microfluidic design criteria to prevent undesirable cell phenotype changes.

METHODOLOGY/PRINCIPAL FINDINGS

A series of microchannels with specific geometric parameters were designed to provide different amount of medium to the cells over time. A medium factor (MF, defined as the volume of stem cell culture medium divided by total number of cells at seeding and number of hours between medium replacement) successfully correlated the amount of medium available to each cell averaged over time to neuronal cell differentiation. MF smaller than 8.3×10(4) µm3/cell⋅hour produced significant neuronal cell differentiation marked by cell morphological change and significantly more cells with positive β-tubulin-III and MAP2 staining than the control. When MF was equal or greater than 8.3×10(4) µm3/cell⋅hour, minimal spontaneous neuronal cell differentiation happened relative to the control. MF had minimal relation with the average neurite length.

SIGNIFICANCE

MFs can be controlled easily to maintain the stem cell status of C17.2 NSCs or to induce spontaneous neuronal cell differentiation in standard stem cell culture medium. This finding is useful in designing microfluidic culture platforms for controllable NSC maintenance and differentiation. This study also offers insight about consumption rate of serum molecules involved in maintaining the stemness of NSCs.

Full factorial screening of human embryonic stem cell maintenance with multiplexed microbioreactor arrays

Use of human pluripotent stem cells (hPSCs) in regenerative medicine applications relies on control of cell fate decisions by exogenous factors. This control can be hindered by the use of undefined culture components, poorly understood autocrine/paracrine effects, spatiotemporal variations in microenvironmental composition inherent to static culture formats, and signal cross-talk between multiple factors. We recently described microbioreactor arrays that provide a full factorial spectrum of exogenous factors, and allow gradual accumulation of paracrine factors through serial culture chambers. We combined these with defined biochemical conditions, and in situ reporter gene- and immunofluorescence-based readouts to create an hPSC screening platform with enhanced data throughput and microenvironmental control. HES3-EOS-C(3+)-EiP reporter hESCs were screened against FGF-2, TGF-β1, and retinoic acid in a modified mTeSR-1 medium background. Differential pluripotency marker expression reflected mTeSR-1's maintenance capacity, and differentiation in response to removal of maintenance factors or addition of retinoic acid. Interestingly, pluripotency marker expression was downregulated progressively through serial chambers. Since downstream chambers are exposed to greater levels of paracrine factors under continuous flow, this effect is thought to result from secreted factors that negatively influence pluripotency. The microbioreactor array platform decodes factor interplay, and has a broad application in deciphering microenvironmental control of cell fate.

Concise review: microfluidic technology platforms: poised to accelerate development and translation of stem cell-derived therapies

Stem cells are a powerful resource for producing a variety of cell types with utility in clinically associated applications, including preclinical drug screening and development, disease and developmental modeling, and regenerative medicine. Regardless of the type of stem cell, substantial barriers to clinical translation still exist and must be overcome to realize full clinical potential. These barriers span processes including cell isolation, expansion, and differentiation; purification, quality control, and therapeutic efficacy and safety; and the economic viability of bioprocesses for production of functional cell products. Microfluidic systems have been developed for a myriad of biological applications and have the intrinsic capability of controlling and interrogating the cellular microenvironment with unrivalled precision; therefore, they have particular relevance to overcoming such barriers to translation. Development of microfluidic technologies increasingly utilizes stem cells, addresses stem cell-relevant biological phenomena, and aligns capabilities with translational challenges and goals. In this concise review, we describe how microfluidic technologies can contribute to the translation of stem cell research outcomes, and we provide an update on innovative research efforts in this area. This timely convergence of stem cell translational challenges and microfluidic capabilities means that there is now an opportunity for both disciplines to benefit from increased interaction.

Microfluidic perfusion culture of human induced pluripotent stem cells under fully defined culture conditions

Human induced pluripotent stem cells (hiPSCs) are a promising cell source for drug screening. For this application, self-renewal or differentiation of the cells is required, and undefined factors in the culture conditions are not desirable. Microfluidic perfusion culture allows the production of small volume cultures with precisely controlled microenvironments, and is applicable to high-throughput cellular environment screening. Here, we developed a microfluidic perfusion culture system for hiPSCs that uses a microchamber array chip under defined extracellular matrix (ECM) and culture medium conditions. By screening various ECMs we determined that fibronectin and laminin are appropriate for microfluidic devices made out of the most popular material, polydimethylsiloxane (PDMS). We found that the growth rate of hiPSCs under pressure-driven perfusion culture conditions was higher than under static culture conditions in the microchamber array. We applied our new system to self-renewal and differentiation cultures of hiPSCs, and immunocytochemical analysis showed that the state of the hiPSCs was successfully controlled. The effects of three antitumor drugs on hiPSCs were comparable between microchamber array and 96-well plates. We believe that our system will be a platform technology for future large-scale screening of fully defined conditions for differentiation cultures on integrated microfluidic devices.

Probing cell-cell communication with microfluidic devices

Intercellular communication is a mechanism that regulates critical events during embryogenesis and coordinates signalling within differentiated tissues, such as the nervous and cardiovascular systems. To perform specialized activities, these tissues utilize the rapid exchange of signals among networks that, while are composed of different cell types, are nevertheless functionally coupled. Errors in cellular communication can lead to varied deleterious effects such as degenerative and autoimmune diseases. However, the intercellular communication network is extremely complex in multicellular organisms making isolation of the functional unit and study of basic mechanisms technically challenging. New experimental methods to examine mechanisms of intercellular communication among cultured cells could provide insight into physiological and pathological processes alike. Recent developments in microfluidic technology allow miniaturized and integrated devices to perform intercellular communication experiments on-chip. Microfluidics have many advantages, including the ability to replicate in vitro the chemical, mechanical, and physical cellular microenvironment of tissues with precise spatial and temporal control combined with dynamic characterization, high throughput, scalability and reproducibility. In this Focus article, we highlight some of the recent work and advances in the application of microfluidics to the study of mammalian intercellular communication with particular emphasis on cell contact and soluble factor mediated communication. In addition, we provide some insights into likely direction of the future developments in this field.

Cell surface concentrations and concentration ranges for testing in vitro autocrine loops and small molecules

A common assumption made when performing in vitro cellular assays is that the concentration of substances in the culture system is uniform. However, since the cells that internalize and secrete substances reside at the bottom of the well, it is conceivable that a concentration gradient could arise across the fluid layer. Importantly, the concentration of a substance in the vicinity of a cell, which is the concentration of interest, cannot be measured via existing methods. In this work a simple strategy for estimating the concentration of a chemical species at the surface of a cell is presented. Finally, this result is used to outline a method for determining the appropriate concentration ranges for testing in vitro autocrine loops and small molecules.

Microbioreactor arrays for full factorial screening of exogenous and paracrine factors in human embryonic stem cell differentiation

Timed exposure of pluripotent stem cell cultures to exogenous molecules is widely used to drive differentiation towards desired cell lineages. However, screening differentiation conditions in conventional static cultures can become impractical in large parameter spaces, and is intrinsically limited by poor spatiotemporal control of the microenvironment that also makes it impossible to determine whether exogenous factors act directly or through paracrine-dependent mechanisms. We detail here the development of a continuous flow microbioreactor array platform that combines full-factorial multiplexing of input factors with progressive accumulation of paracrine factors through serially-connected culture chambers, and further, the use of this system to explore the combinatorial parameter space of both exogenous and paracrine factors involved in human embryonic stem cell (hESC) differentiation to a MIXL1-GFP(+) primitive streak-like population. We show that well known inducers of primitive streak (BMP, Activin and Wnt signals) do not simply act directly on hESC to induce MIXL1 expression, but that this requires accumulation of surplus, endogenous factors; and, that conditioned medium or FGF-2 supplementation is able to offset this. Our approach further reveals the presence of a paracrine, negative feedback loop to the MIXL1-GFP(+) population, which can be overcome with GSK-3β inhibitors (BIO or CHIR99021), implicating secreted Wnt inhibitory signals such as DKKs and sFRPs as candidate effectors. Importantly, modulating paracrine effects identified in microbioreactor arrays by supplementing FGF-2 and CHIR in conventional static culture vessels resulted in improved differentiation outcomes. We therefore demonstrate that this microbioreactor array platform uniquely enables the identification and decoding of complex soluble factor signalling hierarchies, and that this not only challenges prevailing strategies for extrinsic control of hESC differentiation, but also is translatable to conventional culture systems.

Arrayed cellular environments for stem cells and regenerative medicine

The behavior and composition of both multipotent and pluripotent stem cell populations are exquisitely controlled by a complex, spatiotemporally variable interplay of physico-chemical, extracellular matrix, cell-cell interaction, and soluble factor cues that collectively define the stem cell niche. The push for stem cell-based regenerative medicine models and therapies has fuelled demands for increasingly accurate cellular environmental control and enhanced experimental throughput, driving an evolution of cell culture platforms away from conventional culture formats toward integrated systems. Arrayed cellular environments typically provide a set of discrete experimental elements with variation of one or several classes of stimuli across elements of the array. These are based on high-content/high-throughput detection, small sample volumes, and multiplexing of environments to increase experimental parameter space, and can be used to address a range of biological processes at the cell population, single-cell, or subcellular level. Arrayed cellular environments have the capability to provide an unprecedented understanding of the molecular and cellular events that underlie expansion and specification of stem cell and therapeutic cell populations, and thus generate successful regenerative medicine outcomes. This review focuses on recent key developments of arrayed cellular environments and their contribution and potential in stem cells and regenerative medicine.

Microfluidic perfusion for regulating diffusible signaling in stem cells

BACKGROUND

Autocrine & paracrine signaling are widespread both in vivo and in vitro, and are particularly important in embryonic stem cell (ESC) pluripotency and lineage commitment. Although autocrine signaling via fibroblast growth factor-4 (FGF4) is known to be required in mouse ESC (mESC) neuroectodermal specification, the question of whether FGF4 autocrine signaling is sufficient, or whether other soluble ligands are also involved in fate specification, is unknown. The spatially confined and closed-loop nature of diffusible signaling makes its experimental control challenging; current experimental approaches typically require prior knowledge of the factor/receptor in order to modulate the loop. A new approach explored in this work is to leverage transport phenomena at cellular resolution to downregulate overall diffusible signaling through the physical removal of cell-secreted ligands.

METHODOLOGY/PRINCIPAL FINDINGS

We develop a multiplex microfluidic platform to continuously remove cell-secreted (autocrine\paracrine) factors to downregulate diffusible signaling. By comparing cell growth and differentiation in side-by-side chambers with or without added cell-secreted factors, we isolate the effects of diffusible signaling from artifacts such as shear, nutrient depletion, and microsystem effects, and find that cell-secreted growth factor(s) are required during neuroectodermal specification. Then we induce FGF4 signaling in minimal chemically defined medium (N2B27) and inhibit FGF signaling in fully supplemented differentiation medium with cell-secreted factors to determine that the non-FGF cell-secreted factors are required to promote growth of differentiating mESCs.

CONCLUSIONS/SIGNIFICANCE

Our results demonstrate for the first time that flow can downregulate autocrine\paracrine signaling and examine sufficiency of extracellular factors. We show that autocrine\paracrine signaling drives neuroectodermal commitment of mESCs through both FGF4-dependent and -independent pathways. Overall, by uncovering autocrine\paracrine processes previously hidden in conventional culture systems, our results establish microfluidic perfusion as a technique to study and manipulate diffusible signaling in cell systems.

Micro- and nanoengineering for stem cell biology: the promise with a caution

Current techniques used in stem cell research only crudely mimic the physiological complexity of the stem cell niches. Recent advances in the field of micro- and nanoengineering have brought an array of in vitro cell culture models that have enabled development of novel, highly precise and standardized tools that capture physiological details in a single platform, with greater control, consistency, and throughput. In this review, we describe the micro- and nanotechnology-driven modern toolkit for stem cell biologists to design novel experiments in more physiological microenvironments with increased precision and standardization, and caution them against potential challenges that the modern technologies might present.

Optimization of flowrate for expansion of human embryonic stem cells in perfusion microbioreactors

Microfluidic systems create significant opportunities to establish highly controlled microenvironmental conditions for screening pluripotent stem cell fate. However, since cell fate is crucially dependent on this microenvironment, it remains unclear as to whether continual perfusion of culture medium supports pluripotent stem cell maintenance in feeder-free, chemically defined conditions, and further, whether optimum perfusion conditions exist for subsequent use of human embryonic stem cell (hESCs) in other microfludic systems. To investigate this, we designed microbioreactors based on resistive flow to screen hESCs under a linear range of flowrates. We report that at low rates (conditions where glucose transport is convection-limited with Péclet number <1), cells are affected by apparent nutrient depletion and waste accumulation, evidenced by reduced cell expansion and altered morphology. At higher rates, cells are spontaneously washed out, and display morphological changes which may be indicative of early-stage differentiation. However, between these thresholds exists a narrow range of flowrates in which hESCs expand comparably to the equivalent static culture system, with regular morphology and maintenance of the pluripotency marker TG30 in >95% of cells over 7 days. For MEL1 hESCs the optimum flowrate also coincided with the time-averaged medium exchange rate in static cultures, which may therefore provide a good first estimate of appropriate perfusion rates. Overall, we demonstrate hESCs can be maintained in microbioreactors under continual flow for up to 7 days, a critical outcome for the future development of microbioreactor-based screening systems and assays for hESC culture.

Stem cells in microfluidics

Microfluidic techniques have been recently developed for cell-based assays. In microfluidic systems, the objective is for these microenvironments to mimic in vivo surroundings. With advantageous characteristics such as optical transparency and the capability for automating protocols, different types of cells can be cultured, screened, and monitored in real time to systematically investigate their morphology and functions under well-controlled microenvironments in response to various stimuli. Recently, the study of stem cells using microfluidic platforms has attracted considerable interest. Even though stem cells have been studied extensively using bench-top systems, an understanding of their behavior in in vivo-like microenvironments which stimulate cell proliferation and differentiation is still lacking. In this paper, recent cell studies using microfluidic systems are first introduced. The various miniature systems for cell culture, sorting and isolation, and stimulation are then systematically reviewed. The main focus of this review is on papers published in recent years studying stem cells by using microfluidic technology. This review aims to provide experts in microfluidics an overview of various microfluidic systems for stem cell research.

Lab-on-a-chip devices as an emerging platform for stem cell biology

The advent of stem cell based therapies has brought regenerative medicine into an increased focus as a part of the modern medicine practice, with a potential to treat a myriad of intractable diseases in the future. Stem cells reside in a complex microenvironment presenting them with a multitude of potential cues that are chemical, physical, and mechanical in nature. Conventional techniques used for experiments involving stem cells can only poorly mimic the physiological context, and suffer from imprecise spatial and temporal control, low throughput, lack of scalability and reproducibility, and poor representation of the mechanical and physical cell microenvironment. Novel lab-on-a-chip platforms, on the other hand, can much better mimic the complexity of in vivo tissue milieu and provide a greater control of the parameter variation in a high throughput and scalable manner. This capability may be especially important for understanding the biology and cementing the clinical potential of stem cell based therapies. Here we review microfabrication- and microfluidics-based approaches to investigating the complex biology of stem cell responses to changes in the local microenvironment. In particular, we categorize each method based on the types of controlled inputs it can have on stem cells, including soluble biochemical factors, extracellular matrix interactions, homotypic and heterotypic cell-cell signaling, physical cues (e.g. oxygen tension, pH, temperature), and mechanical forces (e.g. shear, topography, rigidity). Finally, we outline the methods to perform large scale observations of stem cell phenotypes and high-throughput screening of cellular responses to a combination of stimuli, and many new emerging technologies that are becoming available specifically for stem cell applications.

Microfluidics-integrated time-lapse imaging for analysis of cellular dynamics

An understanding of the mechanisms regulating cellular responses has recently been augmented by innovations enabling the observation of phenotypes at high spatio-temporal resolution. Technologies such as microfluidics have sought to expand the throughput of these methods, although assimilation with advanced imaging strategies has been limited. Here, we describe the pairing of high resolution time-lapse imaging with microfluidic multiplexing for the analysis of cellular dynamics, utilizing a design selected for facile fabrication and operation, and integration with microscopy instrumentation. This modular, medium-throughput platform enables the long-term imaging of living cells at high numerical aperture (via oil immersion) by using a conserved 96-well, approximately 6 x 5 mm(2) imaging area with a variable input/output channel design chosen for the number of cell types and microenvironments under investigation. In the validation of this system, we examined fundamental features of cell cycle progression, including mitotic kinetics and spindle orientation dynamics, through the high-resolution parallel analysis of model cell lines subjected to anti-mitotic agents. We additionally explored the self-renewal kinetics of mouse embryonic stem cells, and demonstrate the ability to dynamically assess and manipulate stem cell proliferation, detect rare cell events, and measure extended time-scale correlations. We achieved an experimental throughput of >900 cells/experiment, each observed at >40x magnification for up to 120 h. Overall, these studies illustrate the capacity to probe cellular functions and yield dynamic information in time and space through the integration of a simple, modular, microfluidics-based imaging platform.