Control of flow and oxygen in a 3-D perfused micro-environment fosters balanced survival of hepatocyte-non-parenchymal cell co-cultures

Creating a physiologically relevant in vitro liver model requires reproducing the cellular heterogeneity of in vivo liver in a functional state. However differentiated sinusoidal endothelial cells (SECs), marked by SE-1 expression are difficult to maintain in culture while stellate cells easily activate and over-proliferate. We hypothesized that recreating a liver tissue system that captured in vivo like paracrine influences would foster survival of these cells, and predicted that stimuli resulting from flow and oxygen gradients close to physiological conditions would preserve the delicate balance between the cell types. Spheroids containing hepatoctyes with incorporated non-parenchymal cells (NPCs) were seeded into capillary bed sized channels in polycarbonate scaffolds, housed in a three-dimensional perfused system, and maintained for two weeks. Micro-flow rates of different media through the formed tissue units in scaffolds were controlled using pneumatic pumps and microfluidics. Staining and confocal imaging of endpoint tissue showed that lower flow rates closer to physiological regimes allowed the survival of SE-1+ SECs, regardless of exogenously added growth factors in the medium. Higher flow rates, exogenous growth factors, and scaffold contact were associated with activation of stellate cells (alpha-smooth muscle actin staining).

Department dc:contributor.department

Massachusetts Institute of Technology. Biological Engineering Division.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Dash, Ajit

Advisor dc:contributor.advisor

• Linda Griffith and Steven R. Tannenbaum.

• Biological Engineering Division.

Statement dc:rights

• MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/39906

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/39906