Method for engineering three-dimensional synthetic vascular networks through mechanical micromachining and mutable polymer micromolding
The present invention relates generally to a method that is used to create three-dimensional synthetic vascular networks. Micromachining and molding techniques are used to create a template in a shape that mimics a biological network. Cellular material can be seeded around the template or a space created by the template and grown into an engineered tissue-construct.
1. A method for creating a vascularized structure, comprising:
milling a groove on a substrate, wherein the groove forms a pattern that mimics a biologic structure;
transferring the pattern from the substrate to a first mold;
transferring the pattern from the substrate to a second mold, wherein the second mold is a mirror image of the first mold;
joining the first mold and second mold together, forming a micromold having a microchannel with a circular cross-section;
flowing a template material into the microchannel,
wherein the micromold has a dissolution rate that prevents dissolution of the micromold during flowing the template material;
causing the template material to solidify in the microchannel;
dissolving the micromold, leaving a template having a shape of the microchannel;
embedding the template in a growth medium;
solidifying the growth medium;
liquefying and then removing the template material, leaving a cavity in the growth medium in the shape of the template; and
perfusing the cavity with cellular material.
2. The method of claim 1 :
wherein the biologic structure is a vascular network, and
wherein the cellular material is endothelial cells.
3. The method of claim 1 :
wherein the biologic structure is a neural structure, and
wherein the cellular material is neural cells.
4. The method of claim 3 , further comprising:
reducing a diameter of the microchannel before perfusing the cavity.
5. The method of claim 1 , wherein the growth medium is a collagen gel seeded with a second cellular material.
6. The method of claim 1 , wherein the template material comprises a thermally reversible polymer.
7. The method of claim 1 , wherein the micromold is dissolvable in a solvent.
8. The method of claim 7 , wherein the solvent is water.
9. The method of claim 1 , wherein the micromold comprises polydimethylsiloxane.
10. The method of claim 1 , wherein the micromold comprises carboxymethlycellulose.
11. The method of claim 1 , wherein the template material is a gelatin solution.
12. The method of claim 1 , wherein the template material is bioinert and is in a liquid phase at 37° C.
13. The method of claim 1 , further comprising:
assessing attachment of the cellular material to an interior surface of the cavity.
14. The method of claim 1 , further comprising:
creating at least one additional micromold having a second microchannel; and
stacking the at least one additional micromold on top of the micromold, wherein the second microchannel is in fluid communication with the microchannel.
15. The method of claim 1 , wherein the step of joining the first mold and second mold together, forming a micromold having a microchannel with a circular cross-section, further comprises:
using an alignment pin to align the first mold and the second mold.