David J. Beebe

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As the integration of microfluidics into cell biology research proceeds at an ever-increasing pace, a critical question for those working at the interface of both disciplines is which device material to use for a given application. While PDMS and soft lithography methods offer the engineer rapid prototyping capabilities, PDMS as a material has(More)
Microfluidic technology holds great promise for the creation of advanced cell culture models. In this review, we discuss the characterization of cell culture in microfluidic systems, describe important biochemical and physical features of the cell microenvironment, and review studies of microfluidic cell manipulation in the context of these features.(More)
Polydimethylsiloxane (PDMS) has become a staple of the microfluidics community by virtue of its simple fabrication process and material attributes, such as gas permeability, optical transparency, and flexibility. As microfluidic systems are put toward biological problems and increasingly utilized as cell culture platforms, the material properties of PDMS(More)
Kostmann disease is an inherited severe congenital neutropenia syndrome associated with loss-of-function mutations in an adaptor protein HS1-associated protein X-1 (Hax1). How Hax1 regulates neutrophil function remains largely unknown. In this paper, we use ribonucleic acid interference to deplete Hax1 in the neutrophil-like cell line PLB-985 and identify(More)
Stromal fibroblasts of breast carcinomas frequently express the cell surface proteoglycan syndecan-1 (Sdc1). In human breast carcinoma samples, stromal Sdc1 expression correlates with an organized, parallel, extracellular matrix (ECM) fiber architecture. To examine a possible link between stromal Sdc1 and the fiber architecture, we generated bioactive(More)
Interest in constructing a reliable 3-dimensional (3D) collagen culture platform in microfabricated systems is increasing as researchers strive to investigate reciprocal interaction between extracellular matrix (ECM) and cells under various conditions. However, in comparison to conventional 2-dimensional (2D) cell culture research, relatively little work(More)
Microscale techniques have been applied to biological assays for nearly two decades, but haven't been widely integrated as common tools in biological laboratories. The significant differences between several physical phenomena at the microscale versus the macroscale have been exploited to provide a variety of new types of assays (such as gradient production(More)
HS1 is an actin regulatory protein and cortactin homolog that is expressed in hematopoietic cells. Antigen receptor stimulation induces HS1 phosphorylation, and HS1 is essential for T cell activation. HS1 is also expressed in neutrophils; however, the function of HS1 in neutrophils is not known. Here we show that HS1 localizes to the neutrophil leading(More)
The transition of ductal carcinoma in situ (DCIS) to invasive ductal carcinoma (IDC) is a critical step in breast cancer progression. We introduce a simple microfluidic 3D compartmentalized system in which mammary epithelial cells (MCF-DCIS) are co-cultured with human mammary fibroblasts (HMFs), which promotes a transition from DCIS to IDC in vitro. The(More)
The study of angiogenesis is important to understanding a variety of human pathologies including cancer, cardiovascular and inflammatory diseases. In vivo angiogenesis assays can be costly and time-consuming, limiting their application in high-throughput studies. While traditional in vitro assays may overcome these limitations, they lack the ability to(More)