Placental tissue grafts

Patent metadata

Field	Value
Publication number	US-9415074-B2
Application number	US-201514919692-A
Country	US
Kind code	B2
Filing date	Oct 21, 2015
Priority date	Sep 7, 2007
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

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 bilayer tissue graft consisting essentially of
a) a washed, cleaned and dehydrated amnion layer isolated from a placenta;
b) a washed, cleaned and dehydrated chorion layer isolated from a placenta;
wherein the amnion layer has a first side which is an exposed basement membrane and a second side which is a fibroblast layer, and further wherein the chorion is in direct contact with the amnion and the two layers are laminated together.

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

3. The dehydrated, laminated tissue graft of claim 1 , wherein one or both of the amnion layer and the chorion layer are treated with an antibiotic prior to lamination.

4. The dehydrated, laminated tissue graft of claim 1 , wherein the tissue graft has been exposed to sterilizing conditions.

5. A dehydrated, laminated bilayer tissue graft, wherein the tissue graft consists essentially of an amnion layer and a chorion layer, wherein each of the amnion and chorion layers:
a) is separated from a placenta to provide separated layers of amnion and chorion;
b) is washed and substantially cleaned; and
c) is layered directly over the other and heat dehydrated and laminated to provide the dehydrated, laminated bilayer tissue graft;
wherein the amnion has a first side which is an exposed basement membrane and a second side which is a fibroblast layer.

6. The dehydrated, laminated tissue graft of claim 5 , wherein at least one of the amnion layer or chorion layer has been chemically decontaminated.

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

• A61L27/3834

  Cells able to produce different cell types, e.g. hematopoietic stem cells, mesenchymal stem cells, marrow stromal cells, embryonic stem cells · CPC title

• A61K35/19

  Platelets; Megacaryocytes · CPC title

• Y10T156/10

  Methods of surface bonding and/or assembly therefor · 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