Journal: Micromachines

Article Title: Engineered Vasculature for Cancer Research and Regenerative Medicine

doi: 10.3390/mi14050978

Figure Lengend Snippet: Vascular angiogenesis on a chip. ( A ) Schematic of tumor-induced angiogenesis. ( B ) New vessel formation (yellow) from pre-existing vessel toward the GBM spheroid. Scale bar: 100 μm. ( C ) Length and number of neo-vessels toward the GBM spheroid. Significance is indicated by **** for p < 0.0001; all by unpaired t -test). Image A to C are recreated with permission from Seo et al. . Copyright 2022, Wiley-VCH GmbH. ( D ) Schematic illustration of a vascularized liver construct. ( E ) 3D bioprinting to engineer 3D liver tissue construct with central vessel using agarose. ( F ) Microchannels embedded liver construct. The red dye solution was perfused into the hydrogel construct after molding and crosslinking. ( G ) Photographs showing the microfluidics that enable perfusion in the bioreactor. Confocal microscopy images of vasculature construct showing: ( H ) without APAP (control) where the HUVEC layer remains intact and ( I ) with 30 mM of APAP exhibit a damaged vessel. Images D to I are reproduced from Massa et al. with the permission of AIP Publishing.

Article Snippet: For the models of microvasculature specifically, several studies have used the two-lane or three-lane microfluidic plates commercialized by MIMETAS [ , , ].

Techniques: Construct, Confocal Microscopy, Control

Journal: Micromachines

Article Title: Engineered Vasculature for Cancer Research and Regenerative Medicine

doi: 10.3390/mi14050978

Figure Lengend Snippet: Three-dimensional vascularized tumor in vitro systems to model intravasation, extravasation, and invasion. ( A ) Illustration of the 3D lung cancer model that recapitulates blood vessels within a hydrogel composite. ( B ) Microscopic images that highlight the constructed blood vessels (red: HUVECs that express RFP; green: VE-cadherin; blue: DAPI). ( C ) A 3D image of the sprouts grown from the main HUVEC blood vessels. ( D ) A projection of the 3D vascularized lung cancer model (red: RFP-HUVEC and green: GFP-A549). ( E ) A 3D reconstructed view (red: RFP-HUVEC, green: GFP-A549, and blue: DAPI). ( F ) An illustration of a vascularized tumor, in which the movement of immune cells through the small blood vessels is enhanced. ( H ) An illustration of a tumor without vascularization, in which the movement of immune cells is restricted. ( G , I ) More THP1 cells were retained in the area closed to the tumor spheroid in the vascularized than nonvascularized tumor model when THP1 cells are perfused into the main blood vessel (red: RFP-HUVEC, green: GFP-A549, and blue: THP1). Reproduced with permission . Copyright 2022, Wiley-VCH GmbH. ( J ) Metastatic model. ( i ) A photograph of a 3D-printed container used for testing the spread of tumor cells. ( ii , iii ) Three-dimensional images of the top view (upper panel) and cross-section (lower panel) of a small blood vessel lined by HUVECs within a gel made of fibrous protein, showing the interior of the vessel. ( iv ) Microscopic images showing a vessel filled with fluorescent liquid (blue, originally poly(fluorescein isothiocyanate allylamine hydrochloride)). ( v ) A composite image showing a representative model of a tumor before laser-triggered rupture of capsules containing EGF and VEGF (green fluorescence: A549s that express GFP, red fluorescence: HUVECs that express RFP, bright field: fibroblasts). ( K ) A series of microscopic images showing the distribution of A549 cells that express GFP over time, demonstrating guided migration (red circles: EGF capsules; white circle: control capsule without growth factor loading; and cross lines: laser rupture pathways). ( L ) A series of microscopic images showing small blood vessels that sprout from the main vessel and extend in a single direction over time, indicating guided sprouting angiogenesis by VEGF capsules. ( M ) A microscopic image of a metastatic model on day 12, showing that A549 cells move towards and enter the blood vessels through the gel made of fibrous protein and fibroblast cells (green channel: A549 cells that express GFP; red channel: HUVECs that express RFP). Reproduced with permission . Copyright 2019, Wiley. ( N-i ) A diagram of the microfluidic device, showing the central compartment shaded in blue that has the cells surrounded by the small channels filled with liquid (pink). ( N-ii ) A close-up of the central region that contains the cells mixed in a 3D hydrogel at different time points. ( O ) Measurement of the movement of monocytes out of the blood vessels after the introduction of monocytes in the network of small blood vessels. ( P ) 3D images of a monocyte (white) moving through the cells that line the blood vessels (green). ( Q ) A representative image of the monocytes 4 days after the introduction. ( R ) A representative cross-sectional view of a segment of a small blood vessel (green) and the area outside of it, as observed with 3D microscopy and represented in a diagram (right panel). Fibroblast cells (red) are found in the area outside of the 3D matrix made of fibrous protein, while monocytes (white) can be found either inside the hollow vessels or outside of the 3D matrix made of fibrous protein. The scale bar is 10 μm. Reprinted from Biomaterials 198 (2019): 180-93. “The Effects of Monocytes on Tumor Cell Extravasation in a 3d Vascularized Microfluidic Model.” Boussommier-Calleja, A., Y. Atiyas, K. Haase, M. Headley, C. Lewis, and R. D. Kamm. . Copyright 2019, with permission from Elsevier.

Article Snippet: For the models of microvasculature specifically, several studies have used the two-lane or three-lane microfluidic plates commercialized by MIMETAS [ , , ].

Techniques: In Vitro, Construct, Capsules, Fluorescence, Migration, Control, Microscopy

Journal: Proceedings of the National Academy of Sciences of the United States of America

Article Title: Synthetic control of mammalian-cell motility by engineering chemotaxis to an orthogonal bioinert chemical signal

doi: 10.1073/pnas.1402087111

Figure Lengend Snippet: Microscopic analysis of HL-60 neutrophil polarization and cell migration in response to CNO. (A) HL-60 neutrophils coelectroporated with Di and GFP were plated on a fibronectin-coated glass surface and observed by time-lapse microscopy in the presence of a steep, micropipette-generated gradient of CNO. Di- and GFP-expressing cells migrated directionally toward the micropipet. Fluorescent dye Alexa 594 tracer is mixed with CNO solution in micropipet to visualize the diffusive gradient. The micropipet gradient source is marked by a magenta asterisk. Track start locations are marked by black squares, and red triangles mark cell location and direction in each frame. Traces (black and gray) connect track start locations (black squares) and cell location (red triangles). Drug concentration used (at source): 1μM CNO. See Movies S2–S4 for full movies. (B) HL-60 neutrophils stably expressing Di were placed in the fibronectin-coated viewing area of a microfluidic chemotaxis assay device capable of generating a smooth, stable gradient of CNO. Time-lapse microscopy was used to track cell migration, and cell-tracking software was used to quantitate various migration metrics. Cells migrated toward the CNO gradient (trajectories plotted with cell start locations at origin) and show increased track velocity, displacement rate, and directionality compared with basal motility in the presence of vehicle control. Drug concentration used (at source): 200 nM CNO. Mean ± SEM is shown for n = 61 cells tracked (**P < 0.0001 by Student t test). See Movie S5 for full movie.

Article Snippet: The ONIX microfluidic platform with M04G gradient generator plate (CellASIC/EMD Biosciences) was used to study HL-60 neutrophil migration.

Techniques: Migration, Time-lapse Microscopy, Generated, Expressing, Concentration Assay, Stable Transfection, Chemotaxis Assay, Cell Tracking Assay, Software, Control