Systems and methods for assembling tissue grafts

Patent metadata

Field	Value
Publication number	US-11065031-B2
Application number	US-201716344737-A
Country	US
Kind code	B2
Filing date	Oct 30, 2017
Priority date	Oct 28, 2016
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

Systems and methods for assembling a plurality of tissue grafts are provided. A method includes harvesting the plurality of micro tissue grafts from a donor site, arranging the plurality of micro tissue grafts in a desired orientation, forming a tissue construct containing the plurality of micro tissue grafts arranged in the desired orientation, and applying the tissue construct to a recipient site.

First claim

The invention claimed is:

1. A method for assembling a plurality of micro tissue grafts, the method comprising:
a) harvesting the plurality of micro tissue grafts from a donor site;
b) arranging the plurality of micro tissue grafts in a desired orientation, wherein step b) includes placing the plurality of micro tissue grafts in a solution and inducing the plurality of micro tissue grafts to organize in the desired orientation;
c) forming a tissue construct containing the plurality of micro tissue grafts arranged in the desired orientation;
d) applying the tissue construct to a recipient site; and
further comprising applying a coating over a surface of the donor site so that an upper surface of each of the plurality of micro tissue grafts contains the coating.

2. The method of claim 1 , wherein the coating is a hydrophobic coating; and wherein inducing the plurality of micro tissue grafts to organize in the desired orientation includes inducing the plurality of micro tissue grafts to organize in the desired orientation spontaneously due to hydrophobic properties of the coating within the solution.

3. The method of claim 1 , wherein the coating is a magnetic coating; and wherein inducing the plurality of micro tissue grafts to organize in the desired orientation includes applying a magnet over the coating to induce the plurality of micro tissue grafts to organize in the desired orientation.

4. The method of claim 1 , wherein inducing the plurality of micro tissue grafts to organize in the desired orientation includes controlling a flow of the micro tissue grafts in the solution.

5. The method of claim 4 , wherein controlling the flow includes subjecting the solution to orbital motion.

6. The method of claim 1 , wherein the tissue construct in step c) includes the plurality of micro tissue grafts arranged in the desired orientation within a supportive material.

7. The method of claim 6 , wherein the supportive material is a biocompatible matrix.

8. The method of claim 1 , wherein step c) includes maintaining the plurality of micro tissue grafts arranged in the desired orientation using one of a material and a tool in communication with an upper surface of the micro tissue grafts.

9. The method of claim 1 , wherein the desired orientation is a substantially vertical epidermal-dermal orientation.

10. The method of claim 1 and further comprising repeating steps a) through c) to form a plurality of tissue constructs; and step d) includes applying the plurality of tissue constructs to the recipient site side-by-side.

11. The method of claim 1 , wherein step c) includes placing the plurality of micro tissue grafts arranged in the desired orientation in the solution in liquid form; and inducing the solution to solidify to form the tissue construct.

12. A method for assembling a plurality of micro tissue grafts, the method comprising:
a) harvesting the plurality of micro tissue grafts from a donor site;
b) arranging the plurality of micro tissue grafts in a desired orientation, wherein step b) includes placing the plurality of micro tissue grafts in a solution and inducing the plurality of micro tissue grafts to organize in the desired orientation;
c) forming a tissue construct containing the plurality of micro tissue grafts arranged in the desired orientation; and
d) applying the tissue construct to a recipient site,
wherein inducing the plurality of micro tissue grafts to organize in the desired orientation includes controlling a flow of the micro tissue grafts in the solution,
wherein controlling the flow includes routing each of the plurality of micro tissue grafts through a respective fluid channel.

13. A method for assembling a plurality of micro tissue grafts, the method comprising:
a) harvesting the plurality of micro tissue grafts from a donor site;
b) arranging the plurality of micro tissue grafts in a desired orientation;
c) forming a tissue construct containing the plurality of micro tissue grafts arranged in the desired orientation; and
d) applying the tissue construct to a recipient site,
wherein the tissue construct in step c) includes the plurality of micro tissue grafts arranged in the desired orientation within a supportive material, and
wherein step c) includes rolling a strip of the supportive material and attaching the plurality of micro tissue grafts to the strip at spaced-apart intervals during rolling.

14. A method for assembling a plurality of micro tissue grafts, the method comprising:
a) placing an apparatus over a donor site, the apparatus including an array of needles, a matrix with holes corresponding to each of the needles, and a mesh over the matrix;
b) applying a vacuum over the apparatus to pull the plurality of micro tissue grafts through the array of needles and into the holes of the matrix, the mesh trapping the plurality of micro tissue grafts in the holes;
c) removing the matrix from the mesh and the array of needles to form a tissue construct including the plurality of micro tissue grafts within the matrix; and
d) applying the tissue construct to a recipient site.

15. The method of claim 14 , wherein the matrix is a bilayer matrix, and step c) further includes removing one layer of the bilayer matrix to form the tissue construct including the plurality of micro tissue grafts within a remaining layer of the bilayer matrix.

16. The method of claim 14 and further comprising repeating steps a) through c) to form a plurality of tissue constructs; wherein step d) includes applying the plurality of tissue constructs to the recipient site side-by-side.

17. An apparatus for assembling a plurality of micro tissue grafts into a tissue construct, the apparatus comprising:
an array of needles each sized to harvest a respective micro tissue graft from a donor site;
a matrix positioned over the array of needles and including holes configured to receive the micro tissue grafts from the needles; and
a mesh positioned over the matrix, the mesh sized to permit air to pass therethrough so that an applied vacuum pulls the micro tissue grafts through the needles into the matrix, the mesh further sized to contain the micro tissue grafts within the matrix.

18. The apparatus of claim 17 , wherein the matrix includes a biocompatible material.

Assignees

• Massachusetts Gen Hospital

Inventors

• Anderson Richard Rox
• Tam Joshua
• Franco Walfre
• Farinelli William
• Wang Ying
• Purschke Martin

Classifications

• A61B17/322 Primary

  Skin grafting apparatus · CPC title

• A61B2017/00747

  Dermatology · CPC title

• A61B2017/00969

  used for transplantation · CPC title

• A61B2017/3225

  with processing of harvested tissue · CPC title

• A61L27/3691

  characterised by physical conditions of the treatment, e.g. applying a compressive force to the composition, pressure cycles, ultrasonic/sonication or microwave treatment, lyophilisation · CPC title