Patent US4254226A successfully refreshed from Google Patents.
US4254226A
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Process for growing human epidermal cells in tissue culture
Assignee: Memorial Sloan Kettering Cancer Center
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Filing: 1979-09-13
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Granted: 1981-03-03
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Expires: 1999-09-13
Abstract
Abstract Human epidermal cells are grown in tissue culture by separating the epidermis in human skin from the dermis, dissociating the epidermis into epidermal cells, and growing the epidermal cells in a tissue culture medium having a pH of from about 5.6 to about 5.8.
Inventors
- 👤 Magdalena G. Eisinger
- 👤 John M. Hefton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:46
CPC Classifications
C; C12; C12N; C12N5/00; C12N5/06; C12N5/0602; C12N5/0625; C12N5/0629; A; A61; A61K; A61K35/00; A61K35/12; A61K35/36; C12N2500/00; C12N2500/60
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
49 words
Process for growing human epidermal cells in tissue culture which comprises: (i) separating the epidermis in human skin from the dermis; (ii) dissociating the epidermis into epidermal cells; and (iii) growing the epidermal cells in a tissue culture medium having a pH of from about 5.6 to about 5.8.
Claim 2
Dependent Claim
49 words
Process for growing human epidermal cells in tissue culture which comprises: (i) separating the epidermis in human skin from the dermis; (ii) dissociating the epidermis into epidermal cells; and (iii) growing the epidermal cells in a tissue culture medium having a pH of from about 5.6 to about 5.8.
Claim 3
Dependent Claim
20 words
Process of claim 1 wherein clumps or pieces of tissue present after step (ii) are removed prior to step (iii).
Claim 4
Dependent Claim
21 words
Process of claim 1 wherein the culture medium contains from about 5 to about 15 percent by volume fetal calf serum.
Claim 5
Dependent Claim
16 words
Process of claim 3 wherein the culture medium contains about 10% by volume fetal calf serum.
Claim 6
Dependent Claim
41 words
Process of claim 4 wherein the epidermal cells are grown in a tissue culture vessel and the amount of fetal calf serum in the culture medium is reduced to about 5% by volume after the cells become attached to the vessel.
Claim 7
Dependent Claim
26 words
Process of claim 1 wherein the epidermal cells are seeded in the culture medium at a density of from about 5 to about 8×10 5 cells/ml.
Claim 8
Dependent Claim
15 words
Process of claim 1 wherein the cells are grown in the presence of atmospheric air.
Claim 9
Dependent Claim
13 words
Process of claim 7 wherein the air contains about 5% added carbon dioxide.
Claim 10
Dependent Claim
14 words
Process of claim 1 wherein the cells are grown at about 80% relative humidity.
Claim 11
Dependent Claim
16 words
Process of claim 1 wherein the cells are grown at a temperature of about 35°-36° C.
Claim 12
Dependent Claim
36 words
Process of claim 1 wherein the epidermal cells are grown into an epidermal sheet in a tissue culture vessel which is removed from the wall of the vessel by adhering the sheet to a transfer member.
Claim 13
Dependent Claim
17 words
Process of claim 11 wherein the epidermal sheet is adhered to the dermal side of pig skin.
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) | 1984-03-02 | 1984-09-01 | 1985-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-02 | 1988-09-01 | 1989-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-02 | 1992-09-01 | 1993-03-03 | $7700.00 | Window Closed / Lapsed |