US4301249A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High titer production of hepatitis A virus
Assignee: Merck and Co Inc
•
Filing: 1980-07-23
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Granted: 1981-11-17
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Expires: 2000-07-23
Abstract
Abstract Hepatitis A virus (HAV) is produced in high titer from tissue cultures grown on a hollow fiber capillary unit.
Inventors
- 👤 Henry Z. Markus
- 👤 William J. McAleer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:09
CPC Classifications
A; A61; A61K; A61K39/00; A61K39/12; A61K39/29; C; C12; C12N; C12N2770/00; C12N2770/00011; C12N2770/32011; C12N2770/32411; C12N2770/32434; C12N2770/32451; Y; Y02; Y02A; Y02A50/00; Y02A50/30
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
36 words
A method for enhancing the yield of HAV in in vitro cell culture which comprises growing the virus in a susceptible cell culture planted on a hollow fiber capillary unit under conditions which permit viral replication.
Claim 2
Independent Claim
36 words
A method for enhancing the yield of HAV in in vitro cell culture which comprises growing the virus in a susceptible cell culture planted on a hollow fiber capillary unit under conditions which permit viral replication.
Claim 3
Dependent Claim
26 words
A method according to claim 1 wherein the susceptible cell culture is allowed to attach to the hollow fiber capillaries before being infected by the HAV.
Claim 4
Dependent Claim
68 words
A method according to claim 1 wherein the cell culture is grown in two different elevated temperature stages with a first growth stage at an elevated temperature and with a second growth stage at a lower but still elevated temperature which is above room temperature with a purine optionally being present during the second growth stage in an amount effective to improve the yield of hepatitis A virus.
Claim 5
Dependent Claim
20 words
A method according to claim 3 wherein the first growth stage takes place at from 35° to about 38° C.
Claim 6
Dependent Claim
21 words
A method according to claim 3 wherein the second growth stage takes place at from about 30° C. to 34° C.
Claim 7
Dependent Claim
17 words
A method according to claim 1 wherein the second growth stage takes place at about 32° C.
Claim 8
Dependent Claim
23 words
A method according to claim 6 wherein the purine is present in an amount of from about 0.0001 M to about 0.0007 M.
Claim 9
Dependent Claim
23 words
A method according to claim 7 wherein the purine is present in an amount of from about 0.0001 M to about 0.0003 M.
Claim 10
Dependent Claim
11 words
A method according to claim 8 wherein the purine is caffeine.
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) | 1984-11-16 | 1985-05-18 | 1985-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-16 | 1989-05-18 | 1989-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-16 | 1993-05-18 | 1993-11-17 | $7700.00 | Window Closed / Lapsed |