Grant - Microengineered 3D liver tissue engineering and drug screening

Things to do list

1. Reorganize the Aim list and structure of projects

2. Flow chart of 3 aims' connective schematic figure needed

3. Application to drug screening, drug toxicity, gene expression level of hepatocytes.

Original

Aim 1: Microengineer porous cell-laden hydrogels by degradation of microfiber networks.

1.1 Fabricate aligned biodegradable alginate microfibers of controlled shapes using microfluidic channels.

1.2 Generate porous hydrogels by controlled degradation of microfibrous networks.

1.3 Analyze hepatocyte cell viability and proliferation within porous hydrogel networks as a function of time, seeding density, microchannel density and perfusion.

Aim 2: Engineer liver tissue complexity within microengineered cell-laden hydrogels.

2.1 Fabricate cell-laden biodegradable networks of hydrogel tubes with controlled alignment and geometry.

2.2 Generate and characterize microvascularized hydrogels by controlled degradation of cell-laden tubes.

2.3 Fabricate and characterize multi-component porous hydrogels by integrating cell-laden microgels within the hydrogel component of microengineered tissues.

2.4 Characterize vascularized tissues comprised of hepatocyte blocks within fibroblasts containing porous hydrogels.

Aim 3: Develop a microfabricated platform for chemical screening by using 3D engineered liver tissues.

3.1 Develop a microfluidic based platform for generating arrays of microchannels containing bioengineered vascularized liver tissues.

3.2 Perform preliminary studies on the application of the microfluidic screening platform for chemical screening.

Revised (Jan 12 2009) : Changmo Hwang

Aim 1: Microchannel incorporated cell-laden hydrogel by degradation of microfiber networks.

1.1 Fabricate aligned biodegradable alginate microfibers of controlled shapes using microfluidic chip system.

1.2 Generate microchannel structure in cell-laden hydrogels by controlled degradation of microfibrous networks.

1.3 Evaluate biological, mechanical properties of microchannelled cell-laden hydrogel : compare with non porous hydrogel about diffusion, mechanical strength, biodegradability, biocompatibility and albumin production as a liver tissue construct

Aim 2: Engineering vascularized liver tissue with microchannelled cell-laden hydrogels.

2.1 Fabricate cell-laden biodegradable networks of hydrogel tubes with controlled alignment and geometry.

2.2 Generate microvascular structure in cell-laden liver tissue construct in biodegradable hydrogel.

2.3 Characterize cell-laden liver tissue construct with microchannel and with microvascular structure.

2.4 Evaluate the effect of microvascularization on gene expression of hepatocytes in cell-laden hydrogel.

Aim 3: Application of microvascularized liver tissues to chemical and drug screening .

3.1 Incorporate primary cultured hepatocyte in microvascularized cell-laden hydrogel and evaluate liver function.

3.2 Characterize microvascularized liver tissues on liver specific drug.

3.3 Preliminary study in developing a microfluidic based platform for drug screening with microvascularized liver tissue units.

Revised by prof. SH Lee

Aim 1: Construct perforated microchannel in the liver cell-laden hydrogel by degradation of microfiber networks and evaluation of channel’s effect.

1.1 Fabricate aligned and parallel biodegradable alginate microfibers (cylindrical shape) of controlled size using microfluidic chip system.

1.2 Generate cylindrical microchannel structure in liver cell-laden hydrogels by controlled degradation of aligned and parallel fibers embedded in hydrogel.

1.3 Evaluate biological, mechanical properties of microchannelled cell-laden hydrogel: compare with non porous hydrogel about diffusion, mechanical strength, biodegradability, biocompatibility and albumin production as a liver tissue construct

Aim 2: Engineering of 3D liver cell-laden hydrogels having vessel-like (meaning endothelial cell based channel) structure.

2.1 Fabricate endothelial cell -laden alginate hollow fiber with controlled alignment and geometry.

2.2 Generate microvascular structure in liver cell-laden 3D hydrogel structure by degrading endothelial cell-laden alginate hollow.

2.3 Characterize cell-laden liver tissue structure including endothelial cell based vascular structure with appropriate co-culturing environment.

2.4 Evaluate the effect of microvascularization by measuring albumin and urea secretion and by analyzing gene expression of hepatocytes in the hydrogel.

Aim 3: Application of microvascularized liver tissues to toxicity and drug screening.

3.1 Engineering of arrayed 3D liver tissue with vascular-like channel and incorporation with microfluidic chip.

3.2 Preliminary study for the toxicity test using engineered tissue based microfluidic screening system and investigation of potentiality for drug screening