US4330619A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Enzymatic conversion of red cells for transfusion
Assignee: New York Blood Center
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Filing: 1980-08-14
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Granted: 1982-05-18
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Expires: 2000-08-14
Abstract
Abstract A composition comprising type O erythrocyte free of P1 antigenicity; a method of converting erythrocytes of the B antigen type to erythrocytes of the H-antigen type which comprises: A. equilibrating said erythrocytes to a pH of 5.7-5.8; B. thereafter contacting the so-equilibrated erythrocytes with an enzyme for a period sufficient to convert the B antigen in said erythrocytes to the H-antigen; C. thereafter removing said enzyme from said erythrocytes and D. re-equilibrating said erythrocytes to a pH of 7.2-7.4. The specification discloses conversion of the B antigens in human and animal blood to the H antigen (O cells).
Inventors
- 👤 Jack Goldstein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:55
CPC Classifications
A; A61; A61K; A61K35/00; A61K35/12; A61K35/14; A61K35/18; A61P; A61P7/00; A61P7/08
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
71 words
A method of converting erythrocytes of the B or A,B antigen type to erythrocytes of the H-antigen type which comprises: A. equilibrating said erythrocytes to a pH of 5.7-5.8; B. thereafter contacting the so-equilibrated erythrocytes with α-galactosidase for a period sufficient to convert the B antigen in said erythrocytes to the H-antigen; and C. thereafter removing said α-galactosidase from said erythrocytes and D. re-equilibrating said erythrocytes to a pH of 7.2-7.4.
Claim 2
Independent Claim
71 words
A method of converting erythrocytes of the B or A,B antigen type to erythrocytes of the H-antigen type which comprises: A. equilibrating said erythrocytes to a pH of 5.7-5.8; B. thereafter contacting the so-equilibrated erythrocytes with α-galactosidase for a period sufficient to convert the B antigen in said erythrocytes to the H-antigen; and C. thereafter removing said α-galactosidase from said erythrocytes and D. re-equilibrating said erythrocytes to a pH of 7.2-7.4.
Claim 3
Dependent Claim
15 words
A process according to claim 1, wherein said α-galactosidase is in the free enzyme form.
Claim 4
Dependent Claim
14 words
A process according to claim 1, wherein said α-galactosidase is in a supported form.
Claim 5
Dependent Claim
16 words
A process according to claim 3, wherein the support for said α-galactosidase is a soluble support.
Claim 6
Dependent Claim
21 words
A process according to claim 4, wherein said soluble support is selected from the group consisting of dextran and polyethylene glycol.
Claim 7
Dependent Claim
13 words
A process according to claim 3, wherein said support is an insoluble support.
Claim 8
Dependent Claim
20 words
A process according to claim 6, wherein said insoluble support is selected from the group consisting of agarose and cellulose.
Claim 9
Dependent Claim
26 words
A process according to claim 1, wherein the equilibration of the erythrocyte to a pH 5.7-5.8 is effective at 20° to 26° C. with a buffer.
Claim 10
Dependent Claim
13 words
A process according to claim 8, wherein said buffer is a citrate-phosphate buffer.
Claim 11
Dependent Claim
41 words
A process according to claim 9, wherein said α-galactosidase is present in an amount of 100 to 350 enzyme units per 80-600 microliters of cells and the treatment with the α-galactosidase is effected at 22 to 28° C. for 30-150 minutes.
Claim 12
Dependent Claim
39 words
A process according to claim 10, wherein the re-equilibration of the so-contacted erythrocytes is effected over a period of time of 15 to 30 minutes and for a period of time sufficient to remove α-galactosidase from the so-treated erythrocytes.
Claim 13
Dependent Claim
17 words
A process according to claim 1 wherein said α-galactosidase is one derived from a green coffee bean.
References Cited (Backward Citations)
No citation records indexed.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-05-17 | 1985-11-16 | 1986-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-17 | 1989-11-16 | 1990-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-17 | 1993-11-16 | 1994-05-18 | $7700.00 | Window Closed / Lapsed |