US4677968A
Expired / Lapsed
US
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Methods of testing the reaction of various substances on living human skin
Assignee: University of Utah Research Foundation Inc
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Filing: 1986-01-14
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Granted: 1987-07-07
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Expires: 2006-01-14
Abstract
Abstract Methods and testing models for use in testing the effects of substances on human skin without the need for human subjects. The present invention includes a flap having viable, functional human skin on one side and animal skin on the opposite side. Sandwiched between the layers of skin are one or more isolated veins, arteries, and nerves. This isolated vasculature joins the animal and the skin flap. The human skin layer is simply a split thickness skin graft prepared from living, but discarded, human skin. The present invention allows various substances to be applied directly to the human skin. The presence of absence of the substance can then be detected in the blood flowing in the isolated vasculature. Thus, tests involving living human skin can be performed without the need to directly involve human subjects.
Inventors
- 👤 Gerald G. Krueger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:29
CPC Classifications
A; A61; A61B; A61B10/00; A61B10/0035
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
116 words
A method for testing the effects of substances on human skin comprising the steps of: (a) providing an isolated skin flap having a layer of living human skin and a layer of living animal skin, said flap being served by an isolated vasculature attached to a test animal and sandwiched between the layers of skin such that substantially all blood leaving the flap flows through the isolated vasculature; (b) placing a quantity of the substance to be tested in contact with the human skin portion of the skin flap; (c) removing at least one sample of blood from the isolated vasculature as the blood leaves the skin flap; (d) analyzing the contents of the blood removed.
Claim 2
Independent Claim
116 words
A method for testing the effects of substances on human skin comprising the steps of: (a) providing an isolated skin flap having a layer of living human skin and a layer of living animal skin, said flap being served by an isolated vasculature attached to a test animal and sandwiched between the layers of skin such that substantially all blood leaving the flap flows through the isolated vasculature; (b) placing a quantity of the substance to be tested in contact with the human skin portion of the skin flap; (c) removing at least one sample of blood from the isolated vasculature as the blood leaves the skin flap; (d) analyzing the contents of the blood removed.
Claim 3
Dependent Claim
13 words
A method as defined in claim 1 wherein the test animal is athymic.
Claim 4
Dependent Claim
13 words
A method as defined in claim 2 wherein the animal is a mouse.
Claim 5
Dependent Claim
13 words
A method as defined in claim 2 wherein the animal is a rat.
Claim 6
Dependent Claim
22 words
A method as defined in claim 1 wherein the layer of animal skin is located on the abdomen of the test animal.
Claim 7
Dependent Claim
20 words
A method as defined in claim 5 wherein the layer of animal skin is located in the inferior epigastric region.
Claim 8
Dependent Claim
25 words
A method as defined in claim 1 wherein a half-cell diffusion chamber is used to apply the substance to be tested to the skin flap.
Claim 9
Dependent Claim
16 words
A method as defined in claim 1 wherein the substance to be tested comprises a drug.
Claim 10
Dependent Claim
17 words
A method as defined in claim 1 wherein the substance to be tested comprises a toxic substance.
Claim 11
Dependent Claim
16 words
A method as defined in claim 1 wherein the substance to be tested comprises a carcinogen.
Claim 12
Dependent Claim
21 words
A method as defined in claim 1 wherein the substance to be tested is applied to the skin flap using iontophoresis.
Claim 13
Dependent Claim
16 words
A method as defined in claim 1 wherein the substance to be tested comprises a cosmetic.
Claim 14
Independent Claim
201 words
A method for testing the effects of substances on human skin comprising the steps of: (a) obtaining a split thickness skin graft of human skin; (b) isolating an area of the skin of a test animal such that the isolated area of skin forms a neurovascular island attached to the animal; (c) grafting the human skin graft to the subcutaneous surface of the isolated area of skin on the test animal in order to form a skin flap having human skin on one surface and animal skin on the other surface; (d) reimplanting the skin flap into the test animal for a sufficient period of time that the split thickness skin graft and the isolated area of animal skin grow together; (e) after the split thickness skin graft and animal skin have grown together, as described in step (d), raising the flap on the neurovascular island so as to isolate the vasculature which serves the resulting skin flap; (f) placing a quantity of the substance to be tested in contact with the skin flap; (g) removing at least one sample of blood from the isolated vasculature as the blood leaves the skin flap; (h) analyzing the contents of the blood removed.
Claim 15
Independent Claim
201 words
A method for testing the effects of substances on human skin comprising the steps of: (a) obtaining a split thickness skin graft of human skin; (b) isolating an area of the skin of a test animal such that the isolated area of skin forms a neurovascular island attached to the animal; (c) grafting the human skin graft to the subcutaneous surface of the isolated area of skin on the test animal in order to form a skin flap having human skin on one surface and animal skin on the other surface; (d) reimplanting the skin flap into the test animal for a sufficient period of time that the split thickness skin graft and the isolated area of animal skin grow together; (e) after the split thickness skin graft and animal skin have grown together, as described in step (d), raising the flap on the neurovascular island so as to isolate the vasculature which serves the resulting skin flap; (f) placing a quantity of the substance to be tested in contact with the skin flap; (g) removing at least one sample of blood from the isolated vasculature as the blood leaves the skin flap; (h) analyzing the contents of the blood removed.
Claim 16
Dependent Claim
13 words
A method as defined in claim 13 wherein the test animal is athymic.
Claim 17
Dependent Claim
13 words
A method as defined in claim 14 wherein the animal is a mouse.
Claim 18
Dependent Claim
13 words
A method as defined in claim 14 wherein the animal is a rat.
Claim 19
Dependent Claim
22 words
A method as defined in claim 13 wherein the isolated area of skin is located on the abdomen of the test animal.
Claim 20
Dependent Claim
20 words
A method as defined in claim 17 wherein the isolated area of skin is located in the inferior epigastric region.
Claim 21
Dependent Claim
24 words
A method as defined in claim 13 wherein the test animal is treated such that rejection of the split thickness skin graft is prevented.
Claim 22
Dependent Claim
14 words
A method as defined in claim 19 wherein the test animal is given cyclosporine.
Claim 23
Dependent Claim
23 words
A method as defined in claim 17 further comprising the step of transpositioning the skin flap to the dorsum of the test animal.
Claim 24
Dependent Claim
26 words
A method as defined in claim 21 wherein the skin flap is transpositioned to the dorsum of the test animal by way of a subcutaneous tunnel.
Claim 25
Dependent Claim
20 words
A method as defined in claim 13 wherein the substance to be tested is placed on the human skin surface.
Claim 26
Dependent Claim
25 words
A method as defined in claim 13 wherein a half-cell diffusion chamber is used to apply the substance to be tested to the skin flap.
Claim 27
Dependent Claim
16 words
A method as defined in claim 13 wherein the substance to be tested comprises a drug.
Claim 28
Dependent Claim
17 words
A method as defined in claim 13 wherein the substance to be tested comprises a toxic substance.
Claim 29
Dependent Claim
16 words
A method as defined in claim 13 wherein the substance to be tested comprises a carcinogen.
Claim 30
Dependent Claim
16 words
A method as defined in claim 13 wherein the substance to be tested comprises a cosmetic.
Claim 31
Independent Claim
101 words
A method for producing a neurovascular island skin flap on an athymic test animal comprising the steps of: (a) obtaining a split thickness skin graft of skin; (b) isolating an area of the skin of the test animal on the abdomen of the test animal such that the isolated area of skin forms a neurovascular island attached to the animal comprising the superficial epigastric vessels; (c) grafting the split thickness skin graft to the subcutaneous surface of the isolated area of the animal's skin in order to form a skin flap; and (d) isolating the vasculature which serves the skin flap.
Claim 32
Independent Claim
101 words
A method for producing a neurovascular island skin flap on an athymic test animal comprising the steps of: (a) obtaining a split thickness skin graft of skin; (b) isolating an area of the skin of the test animal on the abdomen of the test animal such that the isolated area of skin forms a neurovascular island attached to the animal comprising the superficial epigastric vessels; (c) grafting the split thickness skin graft to the subcutaneous surface of the isolated area of the animal's skin in order to form a skin flap; and (d) isolating the vasculature which serves the skin flap.
Claim 33
Dependent Claim
13 words
A method as defined in claim 29 wherein the animal is a mouse.
Claim 34
Dependent Claim
13 words
A method as defined in claim 29 wherein the animal is a rat.
Claim 35
Dependent Claim
16 words
A method as defined in claim 29 wherein the split thickness skin graft comprises human skin.
Claim 36
Dependent Claim
24 words
A method as defined in claim 29 wherein the test animal is treated such that rejection of the split thickness skin graft is prevented.
Claim 37
Dependent Claim
15 words
A method as defined in claim 33 wherein the test animal is injected with cyclosporan.
Claim 38
Dependent Claim
23 words
A method as defined in claim 29 further comprising the step of transpositioning the skin flap to the dorsum of the test animal.
Claim 39
Dependent Claim
26 words
A method as defined in claim 35 wherein the skin flap is transpositioned to the dorsum of the test animal by way of a subcutaneous tunnel.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-07-06 | 1991-01-05 | 1991-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-06 | 1995-01-05 | 1995-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-06 | 1999-01-05 | 1999-07-07 | $7700.00 | Window Closed / Lapsed |