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

• US 10,406,259 B2
• Filed: 07/20/2017
• Issued: 09/10/2019
• Est. Priority Date: 08/17/2006
• Status: Active Grant

• Current Assignee: Mimedx Group Incorporated
• Original Assignee: Mimedx Group Incorporated
• Inventors: Daniel, John
• Primary Examiner(s): Fox, Allison M
• Application Number:
  US15/655,020
• Publication Number:
  US 20170319628A1
• Time in Patent Office: 782 Days
• Field of Search: None
• CPC Class Codes: A61K 35/50 Placenta; Placental stem cells; Amniotic fluid; Amnion; Amniotic stem cells
• CPC Class Codes: A61L 2300/412 Tissue-regenerating or healing or proliferative agents
• CPC Class Codes: A61L 2300/60 characterised by a special physical form
• CPC Class Codes: A61L 2430/40 Preparation and treatment of biological tissue for implantation, e.g. decellularisation, cross-linking
• CPC Class Codes: A61L 27/3604 characterised by the human or animal origin of the biological material, e.g. hair, fascia, fish scales, silk, shellac, pericardium, pleura, renal tissue, amniotic membrane, parenchymal tissue, fetal tissue, muscle tissue, fat tissue, enamel
• CPC Class Codes: A61L 27/3683 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 Class Codes: A61L 27/3691 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 Class Codes: A61L 27/50 Materials characterised by their function or physical properties , e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
• CPC Class Codes: A61L 27/54 Biologically active materials, e.g. therapeutic substances A61L27/227 takes precedence
• CPC Class Codes: A61L 27/58 Materials at least partially resorbable by the body

Abstract

A method for preparing placenta membrane tissue grafts for medical use, includes obtaining a placenta from a subject, cleaning the placenta, separating the chorion tissue from the amniotic membrane, mounting a selected layer of either the chorion tissue or the amniotic membrane onto a drying fixture, dehydrating the selected layer on the drying fixture, and cutting the selected layer into a plurality of tissue grafts. Preferably, the drying fixture includes grooves or raised edges that define the outer contours of each desired tissue graft, after they are cut, and further includes raised or indented logos that emboss the middle area of the tissue grafts during dehydration and that enables an end user to distinguish the top from the bottom side of the graft. The grafts are comprised of single layers of amnion or chorion, multiple layers of amnion or chorion, or multiple layers of a combination of amnion and chorion.

Claims

1. A package comprising a sealed, deoxygenated container, said sealed, deoxygenated container comprising a dehydrated placental tissue graft, wherein said graft has a shelf-life of at least 5 years when stored in said container at room temperature;

wherein said graft comprises a first layer which is a separated and washed amnion layer which comprises an epithelial cell layer, and a second layer which is a separated and washed amnion or chorion layer, and

wherein the first and second layers are directly laminated to each other.

2. The package of claim 1, wherein said graft is embossed.

3. The package of claim 1, wherein said graft comprises a groove.

4. The package of claim 1, wherein said graft has been chemically decontaminated prior to placement in the container.

5. The package of claim 1, wherein the second layer of said graft is a chorion layer.

6. The package of claim 1, wherein said graft consists essentially of said first layer which is a separated and washed amnion layer which comprises an epithelial cell layer, and a second layer which is a chorion layer.

7. The package of claim 1, wherein said sealed, deoxygenated container is a pouch.

8. The package of claim 7, wherein said pouch is an inner pouch.

9. The package of claim 7, wherein said sealed, deoxygenated container is heat sealed.

10. The package of claim 1, further comprising an outer container.

11. The package of claim 10, wherein said sealed, deoxygenated container is disposed within said outer container.

12. The package of claim 10, wherein said outer container is a pouch.