Journal: Journal of biomedical materials research. Part A

Article Title: Artificial Lymphatic Drainage Systems for Vascularized Microfluidic Scaffolds

doi: 10.1002/jbm.a.34524

Figure Lengend Snippet: Endothelial delamination in the absence of drainage. (A) Relevant dimensions of the vascularized, undrained fibrin scaffold. Microvessels were constructed by growing blood microvessel-derived endothelial cells in microfluidic channels (120 μm diameter) inside fibrin gels. The length of microvessels was 8.1 ± 0.3 mm, and the thickness of the scaffold was 1.1 mm. (B) Phase-contrast images of microvessels that were perfused for 3 days in fibrin scaffolds of the indicated concentrations. (C) Brightfield images of microvessels that were perfused for 9 days; endothelial delamination is indicated. (D–E) Method for generating delamination frequency maps. (D) Black and white bars were used to highlight stable and delaminated regions, respectively, producing binary delamination maps along the entire length (as shown in (E)) on each side of the vessel; as such, two maps were obtained per vessel. (E) These binary maps were then stacked and their intensity averaged, to generate delamination frequency maps. (F) Frequency maps of delamination (6 mg/mL, 2n = 30; 8 mg/mL, 2n = 22; 10 mg/mL, 2n = 22; 15 mg/mL, 2n = 24; 30 mg/mL, 2n = 34). Brighter regions indicate higher delamination frequency. (G) Delaminated length expressed as a fraction of the total length. (H) Hydraulic conductivities of fibrin gels. (I) Flow rates of microvessels in 30 mg/mL scaffolds in the undrained and T-junction drainage conditions (δ = 0.5 mm and 6.5 mm).

Article Snippet: Cell culture We cultured endothelial cells derived from human dermal blood microvessels (lot 0040804.2 from PromoCell, and lot 5F1293 from Lonza) at 37°C in 5% CO 2 .

Techniques: Construct, Derivative Assay

Journal: Journal of biomedical materials research. Part A

Article Title: Artificial Lymphatic Drainage Systems for Vascularized Microfluidic Scaffolds

doi: 10.1002/jbm.a.34524

Figure Lengend Snippet: Drainage stabilized microvessels locally. (A) Addition of a T-junction gel compartment in the middle of the scaffold. The drainage channel was connected to a media reservoir at the end of this compartment, which was held at 0 cm H2O (see Fig. 1C and D). The distance from the axis of the microvessel to the drainage channel is indicated by δ. The length of microvessels was 8.2 ± 0.3 mm, and the fibrin scaffold was 1.1 mm thick. (B) Phase-contrast image of the T-junction in a 30 mg/mL scaffold. (C) Delamination frequency maps of microvessels in 30 mg/mL scaffolds with different δ values, and 20 mg/mL scaffold with δ = 0.5 mm (0.52 ± 0.08 mm, 2n = 26). Conditions for 30 mg/mL scaffold are δ = 0.5 mm (0.47 ± 0.09 mm, 2n = 22), δ = 1 mm (1.02 ± 0.06 mm, 2n = 24), δ = 1.5 mm (1.48 ± 0.10 mm, 2n = 22), δ = 2.5 mm (2.45 ± 0.17 mm, 2n = 20), and δ ~ 6.5 mm (without drainage channel, 2n = 18). (D) Plot of the continuous stable lengths in the middle of vessels.

Article Snippet: Cell culture We cultured endothelial cells derived from human dermal blood microvessels (lot 0040804.2 from PromoCell, and lot 5F1293 from Lonza) at 37°C in 5% CO 2 .

Techniques:

Journal: Journal of biomedical materials research. Part A

Article Title: Artificial Lymphatic Drainage Systems for Vascularized Microfluidic Scaffolds

doi: 10.1002/jbm.a.34524

Figure Lengend Snippet: Perfusion and drainage of the centimeter-scale fibrin scaffolds (i.e., fibrin patches). (A) Dimensions of the fibrin patch. The average length of microvessels was 8.7 ± 0.2 mm, and the fibrin patch was 1.6 mm thick. (B) Numerical prediction of pressure profiles and vascular stability in the presence and absence of drainage microchannels, using a vessel LP of 3.2 × 10−10 cm3/dyn·s and a corresponding threshold transmural pressure of 1.14 cm H2O (Table 1). These models predicted that the presence of drainage channels maintained above-threshold transmural pressures in more than 89% of the lengths of vessels, whereas the absence of drainage channels would lead to sub-threshold transmural pressures everywhere. (C) Brightfield images on day 9 post-seeding. The drainage channel underneath the microvessel was not in focus. (D) Delamination frequency maps. Vessels v1 to v4 refer to the ones in (A) (with drainage channel, 2n = 18; without drainage channels, 2n = 14). (E) Delaminated length as a fraction of total vessel length. (F) Normalized flow rate of vascularized fibrin patches.

Article Snippet: Cell culture We cultured endothelial cells derived from human dermal blood microvessels (lot 0040804.2 from PromoCell, and lot 5F1293 from Lonza) at 37°C in 5% CO 2 .

Techniques: