US5595571A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Biological material pre-fixation treatment
Assignee: Envveno Medical Corp
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Filing: 1994-04-18
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Granted: 1997-01-21
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Expires: 2014-04-18
Abstract
Abstract Disclosed is a controlled autolysis method for making biological tissue substantially acellular by exposing the biological material, prior to any fixation thereof, to at least one buffered solution having a pH in the range from about 5.0 to 8.0 and a temperature in the range from about 12° C. to 30° C. for a sufficient period of time to render at least one region of the biological material substantially acellular while substantially preserving the structural integrity and non-cellular structural components of the biological material. Also disclosed is a method of making a bioprosthetic heart valve using biological material that has been treated by controlled autolysis and a method of treating a mammal having a defective heart valve using a bioprosthetic heart valve made, in part, by controlled autolysis.
Inventors
- 👤 Norman Jaffe
- 👤 Warren B. Hancock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:43
CPC Classifications
A; A61; A61L; A61L27/00; A61L27/36; A61L27/3683; A61L27/3604; A61L27/3641; A61L27/3645; A61L27/3687; A61L27/3691; A61L27/50; A61L27/507; A61L2430/00; A61L2430/20; Y; Y10; Y10S; Y10S623/00; Y10S623/901; Y10S623/915
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
125 words
A controlled autolysis method for making a biological material substantially acellular, wherein the biological material that is to be made substantially acellular has structural integrity and comprises cells and non-cellular structural components, the controlled autolysis method comprising the step of: exposing the biological material, prior to any fixation thereof, to at least one buffered solution having a pH in the range from about 5.0 to about 8.0 and a temperature in the range from about 12° C. to about 30° C. for a sufficient period of time to permit autolytic enzymes within the cells to degrade said cells, whereby at least one region of the biological material is rendered substantially acellular while preserving the overall structural integrity and non-cellular structural components of the biological material.
Claim 2
Dependent Claim
125 words
A controlled autolysis method for making a biological material substantially acellular, wherein the biological material that is to be made substantially acellular has structural integrity and comprises cells and non-cellular structural components, the controlled autolysis method comprising the step of: exposing the biological material, prior to any fixation thereof, to at least one buffered solution having a pH in the range from about 5.0 to about 8.0 and a temperature in the range from about 12° C. to about 30° C. for a sufficient period of time to permit autolytic enzymes within the cells to degrade said cells, whereby at least one region of the biological material is rendered substantially acellular while preserving the overall structural integrity and non-cellular structural components of the biological material.
Claim 3
Dependent Claim
18 words
The method of claim 1, additionally comprising the step of fixing the biological material after the exposing step.
Claim 4
Dependent Claim
43 words
The method of claim 1, wherein the biological material is derived from at least one animal selected from the group consisting of a bovine, a porcine, an ovine, a Macropodidae, a nonhuman primate, a human and a combination of any of the foregoing.
Claim 5
Dependent Claim
14 words
The method of claim 1, wherein the biological material is derived from a porcine.
Claim 6
Dependent Claim
51 words
The method of claim 1, wherein the biological material is at least one material selected from the group consisting of diaphragm, pericardium, heart valve, umbilical cord, artery, vein, facia lata, dura mater, tendon, ligament, tympanic membrane, a fragment of any of the foregoing and a combination of any of the foregoing.
Claim 7
Dependent Claim
35 words
The method of claim 1, wherein the biological material is at least one material selected from the group consisting of a heart valve, a fragment of a heart valve and a combination of the foregoing.
Claim 8
Dependent Claim
16 words
The method of claim 1, wherein the biological material is a leaflet of a heart valve.
Claim 9
Dependent Claim
43 words
The method of claim 1, wherein the noncellular structural components include at least one structural component selected from the group consisting of collagen, elastin, laminin, teninsin, actinin, proteoglycans, a fragment of any of the foregoing and a combination of any of the foregoing.
Claim 10
Dependent Claim
39 words
The method of claim 1, wherein the buffered solution is at least one solution selected from the group consisting of sodium phosphate monobasic buffer, sodium phosphate dibasic buffers, phosphate citrate buffer and a combination of any of the foregoing.
Claim 11
Dependent Claim
19 words
The method of claim 9, wherein the buffered solution is a combination of sodium phosphate monobasic and dibasic buffers.
Claim 12
Dependent Claim
16 words
The method of claim 1, wherein the pH range is from about 6.0 to about 8.0.
Claim 13
Dependent Claim
16 words
The method of claim 11, wherein the pH range is from about 7.2 to about 7.6.
Claim 14
Dependent Claim
18 words
The method of claim 1, wherein the temperature range is from about 19° C. to about 23° C.
Claim 15
Dependent Claim
19 words
The method of claim 1, wherein the period of time is from about 24 hours to about 100 hours.
Claim 16
Dependent Claim
19 words
The method of claim 1, wherein the period of time is from about 65 hours to about 75 hours.
Claim 17
Dependent Claim
75 words
A method of making a bioprosthetic heart valve, comprising the steps of: (a) subjecting biological material to the controlled autolysis method of claim 1, wherein the biological material comprises a heart valve or a fragment of a heart valve, the heart valve or fragment of a heart valve comprising at least one leaflet; (b) fixing the biological material; and (c) fabricating the bioprosthetic heart valve from the biological material by the addition of non-biological material.
Claim 18
Dependent Claim
22 words
The method of claim 16, wherein the non-biological material comprises a stent, wherein the stent is adapted to permit blood flow therethrough.
Claim 19
Dependent Claim
28 words
The method of claim 16, wherein the region of the biological material that is rendered substantially acellular by the controlled autolysis method is the at least one leaflet.
References Cited (Backward Citations)
US4050893A
Cited
US4083066A
Cited
US4120649A
Cited
DE2715466A1
Cited
US4239492A
Cited
US4383832A
Cited
US4378224A
Cited
US4323358A
Cited
US4648881A
Cited
US4647283A
Cited
US4704131A
Cited
US4405327A
Cited
US4402697A
Cited
WO1984001894A1
Cited
US5215541A
Cited
US4885005A
Cited
EP0128706A2
Cited
US4801299A
Cited
GB2169386A
Cited
US4553974A
Cited
US4770665A
Cited
US4729139A
Cited
US4996054A
Cited
US4776853A
Cited
US4786287A
Cited
US4798611A
Cited
US4800603A
Cited
US4838888A
Cited
US4976733A
Cited
US5094661A
Cited
US5002566A
Cited
US5145771A
Cited
CA2089336A1
Cited
US5336616A
Cited
US5104405A
Cited
US5192312A
Cited
EP0564786A2
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-01-21 | 2000-07-22 | 2001-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-01-21 | 2004-07-22 | 2005-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-01-21 | 2008-07-22 | 2009-01-21 | $7700.00 | Window Closed / Lapsed |