system after rotational cell seeding, followed by low flow media-

perfusion for 5 days. The setup allows medium sampling and

describes the implementation of intraluminal cell proliferation and

functional assays to determine endothelial cell function and the

histological characterization of the seeded cell constructs. Next to

the 3D printed bioreactors, the system consists of common labora-

tory equipment such as pumps, filters and Luer Lock connectors

and is therefore easy to set up by common lab equipment.

It should be noted that today 3D printing has become an

affordable methodology that can be applied in many laboratories.

The above-mentioned methods can easily be adopted to tubular

vascular grafts with other dimensions by printing customized

bioreactors.

Thus, we describe an efficient, reliable, and affordable method

for evaluating the initial adherence and proliferation of endothelial

cells on tubular, acellular vascular grafts under in vitro dynamic

conditions.

2

Materials

2.1

Bioreactor Setup

The applied bioreactor was designed as a straight perfusion cham-

ber with two barb connectors for direct connection of the tubing

(from the outside) to the perfused grafts (on the inside) and recir-

culation of leaking medium.

1. Bioreactor chamber (see Note 1).

2. Tubing:

(a)

1 pump hose (PharMed BPT).

(b)

Silicon tubing (inner diameter 3 mm).

(c)

Female Luer Lock Style to barb connector (according to

used tubing diameters).

(d)

Male Luer Lock Style to barb connector (according to

used tubing diameters).

(e)

Y-connector 3–5 mm.

(f)

Three-way stopcock.

(g)

Sealing caps.

3. Syringes:

(a)

10 ml syringe with Luer Lock fitting.

(b)

50 ml syringe with Luer Lock fitting.

4. Reservoir bottle with three inlets and outlets for media trans-

port (see Note 2). We used a total of 50 ml of media for

approximately 2.5 cm² of reseeded luminal surface area and

chose a 100 ml Schott Duran flask for reservoir.

In Vitro Colonization of Vascular Grafts

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