US4769317A
Expired / Lapsed
US
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Process for growing human epidermis, product thereof
Assignee: Individual
•
Filing: 1983-06-14
•
Granted: 1988-09-06
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Expires: 2003-06-14
Abstract
Abstract Procedures are disclosed for eliminating immune competent cells from a population of human epidermal cells. The cells free of immune competent cells are used for growing tissue sheets suitable for transplantation to recipients unrelated to the donor.
Inventors
- 👤 John M. Hefton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 04:11
CPC Classifications
C; C12; C12N; C12N5/00; C12N5/06; C12N5/0602; C12N5/0625; C12N5/0629; A; A61; A61F; A61F2/00; A61F2/02; A61F2/10; A61K; A61K35/00; A61K35/12; A61K35/36; A61L; A61L27/00; A61L27/36; A61L27/50; A61L27/60; C12N2509/00
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
108 words
In a process for growing human epidermal cells in tissue culture in which the epidermis in human skin is separated from the dermis, the epidermis is dissociated into dissociated epidermal cells comprising immune competent and non-immune competent cells and the dissociated epidermal cells are grown in tissue culture medium to form a sheet of epidermal cells, the improvement which comprises treating a sub-population of dissociated human epidermal cells with DNase in an amount sufficient to segregate immune competent cells from non-immune competent cells, thereafter recovering the non-immune competent cells as single cells, and growing an integral, self-supporting sheet of nonimmune competent epidermal cells from said sub-population of cells.
Claim 2
Dependent Claim
108 words
In a process for growing human epidermal cells in tissue culture in which the epidermis in human skin is separated from the dermis, the epidermis is dissociated into dissociated epidermal cells comprising immune competent and non-immune competent cells and the dissociated epidermal cells are grown in tissue culture medium to form a sheet of epidermal cells, the improvement which comprises treating a sub-population of dissociated human epidermal cells with DNase in an amount sufficient to segregate immune competent cells from non-immune competent cells, thereafter recovering the non-immune competent cells as single cells, and growing an integral, self-supporting sheet of nonimmune competent epidermal cells from said sub-population of cells.
Claim 3
Dependent Claim
15 words
The process of claim 1 wherein the concentration of DNase is about 1.0 to 0.6%.
Claim 4
Dependent Claim
23 words
The process of claim 2 wherein the treatment is carried out at about 20° to 25° C. for about 10 to 60 minutes.
Claim 5
Dependent Claim
16 words
The process of claim 1 wherein the recovered non-immune competent cells consist of ATPase negative cells.
Claim 6
Dependent Claim
50 words
The process of claim 1 wherein the amount of the DNase is selected so as to result in formation of clumps comprising the immune competent cells and fragments of cells, thereafter said clumps are separated from single cells consisting essentially of non-immune competent cells and said single cells are recovered.
Claim 7
Dependent Claim
16 words
The process of claim 5 wherein the recovered non-immune competent cells consist of ATPase negative cells.
Claim 8
Dependent Claim
15 words
The process of claim 5 wherein the concentration of DNase is about 0.1 to 0.6%.
Claim 9
Dependent Claim
23 words
The process of claim 7 wherein the treatment is carried out at about 20° to 25° C. for about 10 to 60 minutes.
Claim 10
Dependent Claim
20 words
The process of any of claims 2,3,7 or 8 wherein the recovered non-immune competent cells consist of ATPase negative cells.
Claim 11
Dependent Claim
20 words
The process of claim 1 wherein the recovered non-immune competent cells consist of cells which do not express HLA-Dr antigen.
Claim 12
Dependent Claim
20 words
The process of claim 5 wherein the recovered non-immune competent cells consist of cells which do not express HLA-Dr antigen.
Claim 13
Dependent Claim
19 words
The process of claim 4 wherein the sub-population of cells consists of cells which do not express HLA-Dr antigen.
Claim 14
Dependent Claim
19 words
The process of claim 6 wherein the sub-population of cells consists of cells which do not express HLA-Dr antigen.
Claim 15
Dependent Claim
19 words
The process of claim 9 wherein the sub-population of cells consists of cells which do not express HLA-Dr antigen.
Claim 16
Dependent Claim
20 words
The process of claim 1 wherein the tissue culture is carried out at a pH of about 6.5 to 7.2.
Claim 17
Dependent Claim
20 words
The process of claim 5 wherein the tissue culture is carried out at a pH of about 6.5 to 7.2.
Claim 18
Dependent Claim
24 words
The process of claim 15 wherein the tissue culture medium is seeded at a density of 10 5 to 10 8 cells per milliliter.
Claim 19
Dependent Claim
24 words
The process of claim 16 wherein the tissue culture medium is seeded at a density of 10 5 to 10 8 cells per milliliter.
Claim 20
Dependent Claim
31 words
The process of claim 1 wherein the sheet of epidermal cells attaches to a tissue culture vessel and the sheet is detached from the vessel by treating with a neutral protease.
Claim 21
Dependent Claim
28 words
The process of claim 1 wherein the separation of the epidermis from the dermis is aided by incubation of the skin in a 0.3 to 0.75% trypsin solution.
Claim 22
Dependent Claim
10 words
The epidermal sheet produced by the process of claim 1.
Claim 23
Dependent Claim
10 words
The epidermal sheet produced by the process of claim 5.
Claim 24
Dependent Claim
10 words
The epidermal sheet produced by the process of claim 3.
Claim 25
Dependent Claim
24 words
A self-supporting epidermal sheet grown in tissue culture and consisting essentially of non-immune competent human epidermal cells being essentially free of immune competent cells.
Claim 26
Dependent Claim
24 words
A self-supporting epidermal sheet grown in tissue culture and consisting essentially of non-immune competent human epidermal cells being essentially free of immune competent cells.
Claim 27
Dependent Claim
14 words
The epidermal sheet of claim 24 wherein said sheet consists of ATPase negative cells.
Claim 28
Dependent Claim
13 words
The epidermal sheet of claim 24 wherein said sheet consists of HLA-Dr-negative cells.
Claim 29
Dependent Claim
13 words
The epidermal sheet of claim 25 wherein said sheet consists of HLA-Dr-negative cells.
Claim 30
Dependent Claim
11 words
The epidermal sheet of claim 24 consisting of non-immune competent cells.
References Cited (Backward Citations)
US4254266A
Cited
US4304866A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-09-06 | 1992-03-07 | 1992-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-06 | 1996-03-07 | 1996-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-06 | 2000-03-07 | 2000-09-06 | $7700.00 | Window Closed / Lapsed |