Placental tissue grafts and improved methods of preparing and using the same

Patent metadata

Field	Value
Publication number	US-9789137-B2
Application number	US-201514804156-A
Country	US
Kind code	B2
Filing date	Jul 20, 2015
Priority date	Sep 7, 2007
Publication date	Oct 17, 2017
Grant date	Oct 17, 2017

Abstract

Described herein are tissue grafts derived from the placenta. The grafts are composed of at least one layer of amnion tissue where the epithelium layer has been substantially removed in order to expose the basement layer to host cells. By removing the epithelium layer, cells from the host can more readily interact with the cell-adhesion bio-active factors located onto top and within of the basement membrane. Also described herein are methods for making and using the tissue grafts. The laminin structure of amnion tissue is nearly identical to that of native human tissue such as, for example, oral mucosa tissue. This includes high level of laminin-5, a cell adhesion bio-active factor show to bind gingival epithelia-cells, found throughout upper portions of the basement membrane.

First claim

What is claimed is:

1. A dehydrated, laminated placental tissue graft which is a laminate comprising a washed amnion layer which has a first side which is an exposed basement membrane and a second side which is a fibroblast layer, and a second layer which is a washed amnion or a washed chorion, wherein said amnion layer and said second layer are dehydrated and laminated directly to each other;
wherein said amnion layer and said second layer are not held in together with a suture.

2. The graft of claim 1 , wherein the amnion layer and the washed chorion are isolated from the same placenta.

3. The graft of claim 1 , wherein one or both of the amnion layer and the second layer are treated with antibiotic prior to lamination.

4. The graft of claim 1 , wherein one or both of the amnion layer and the second layer are chemically decontaminated.

5. The graft of claim 1 , wherein the tissue graft is exposed to sterilizing conditions.

6. The graft of claim 1 , wherein one or both of the amnion layer and the second layer are washed and substantially cleaned.

7. The graft of claim 1 , wherein one or both of the amnion layer and the second layer are heat dehydrated.

8. The graft of claim 1 , wherein one or both of the amnion layer and the second layer comprise a naturally occurring factor, a platelet concentrate, a bone marrow aspirate, a stem cell, or an antibiotic.

9. The graft of claim 1 , wherein the second layer is laminated to the fibroblast layer.

Assignees

• Mimedx Group Inc

Inventors

• Daniel John
• Spencer Randall
• Russo John
• Tofe Robert

Classifications

• A61P41/00

  Drugs used in surgical methods, e.g. surgery adjuvants for preventing adhesion or for vitreum substitution · CPC title

• Y10T156/1039

  Surface deformation only of sandwich or lamina [e.g., embossed panels] · CPC title

• A61L27/56

  Porous materials, {e.g. foams or sponges} · CPC title

• A61F2230/00

  Geometry of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof · CPC title

• A61L27/3683 Primary

  subjected to a specific treatment prior to implantation, e.g. decellularising, demineralising, grinding, cellular disruption/non-collagenous protein removal, anti-calcification, crosslinking, supercritical fluid extraction, enzyme treatment · CPC title