US4888291A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Human epithelium originating from cell cultures
Assignee: Harvard University
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Filing: 1987-06-19
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Granted: 1989-12-19
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Expires: 2007-06-19
Abstract
Abstract Generating a human epithelium on a living animal by a method in which cultured human keratinocytes are placed in contact with the subdermal connective tissue of a non-human animal.
Inventors
- 👤 Yann Barrandon
- 👤 Howard Green
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 09:37
CPC Classifications
A; A61; A61L; A61L27/00; A61L27/50; A61L27/60; C; C12; C12N; C12N5/00; C12N5/06; C12N5/0697; C12N5/0698; C12N2502/00; C12N2502/09; C12N2502/094; C12N2502/13; C12N2502/1323; C12N2533/00; C12N2533/30; Y; Y10; Y10S; Y10S623/00; Y10S623/915
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
63 words
A method of growing an epithelial sheet comprising culturing disaggregated human keratinocytes and placing said human keratinocytes in direct contact with the living subdermal connective tissue of a living non-human animal, and maintaining said connective tissue as living tissue in contact with dermis of said non-human mammal, said connective tissue being positioned between said human kertinocytes and said dermis of said non-human mammal.
Claim 2
Independent Claim
63 words
A method of growing an epithelial sheet comprising culturing disaggregated human keratinocytes and placing said human keratinocytes in direct contact with the living subdermal connective tissue of a living non-human animal, and maintaining said connective tissue as living tissue in contact with dermis of said non-human mammal, said connective tissue being positioned between said human kertinocytes and said dermis of said non-human mammal.
Claim 3
Dependent Claim
27 words
The method of claim 1 comprising culturing disaggregated human keratinocytes to form a confluent culture and contacting said confluent culture with subdermal connective tissue of said animal.
Claim 4
Dependent Claim
19 words
The method of claim 2 wherein said confluent culture is placed on a plastic membrane prior to said contacting.
Claim 5
Dependent Claim
40 words
The method of claim 1 or claim 2 in which said human keratinocytes are placed in direct contact with living subdermal connective tissue by incising a flap of skin of said animal and positioning said cultured keratinocytes beneath said flap.
Claim 6
Dependent Claim
25 words
The method of claim 4 further comprising fastening said flap of skin to said animal after positioning said cultured keratinocytes in contact with said flap.
Claim 7
Dependent Claim
28 words
The method of claim 4 wherein, after positioning said keratinocytes beneath said flap, a mature epidermis is formed beneath the flap, and the flap and epidermis are everted.
Claim 8
Dependent Claim
59 words
The method of claim 1 or claim 2 in which said human keratinocytes are placed in direct contact with living subdermal connective tissue by: (a) incising a flap of skin of said animal; (b) everting said skin to expose the inner surface of said skin; and (c) positioning said keratinocytes in contact with said inner surface of said skin.
Claim 9
Dependent Claim
23 words
The method of claim 8 comprising fastening said flap or skin to said animal after positioning said keratinocytes in contact with said flap.
Claim 10
Dependent Claim
25 words
The method of claim 2 wherein said dissaggregated keratinocytes are epidermal cells which are grown in culture to form an epithelium prior to said contacting.
Claim 11
Dependent Claim
21 words
The method of claim 1 or claim 2 wherein said subdermal connective tissue is adjacent to the dermis of said animal.
Claim 12
Dependent Claim
16 words
The method of claim 1 or claim 2 wherein said subdermal connective tissue contains panniculus carnosus.
Claim 13
Dependent Claim
23 words
The method of claim 1 wherein disaggregated keratinocytes are grown to subconfluence on a plastic membrane and contacted with said subdermal connective tissue.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-12-18 | 1993-06-19 | 1993-12-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-12-18 | 1997-06-19 | 1997-12-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-12-18 | 2001-06-19 | 2001-12-19 | $7700.00 | Window Closed / Lapsed |