US4532203A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluorescent determination of microlymphocytotoxicity
Assignee: Siemens Healthcare Diagnostics GmbH Germany
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Filing: 1982-10-26
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Granted: 1985-07-30
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Expires: 2002-10-26
Abstract
Abstract Improved results are achieved in fluorochromasia lymphocytotoxicity for cell typing by adding antifluorescer to reduce background fluorescence as a result of cell lysing.
Inventors
- 👤 Edwin F. Ullman
- 👤 F. Carl Grumet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:06
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/569; G01N33/56966; G01N33/56972; Y; Y10; Y10S; Y10S435/00; Y10S435/962; Y10S435/963; Y10S435/966; Y10S436/00; Y10S436/80; Y10S436/821; Y10S436/824
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
81 words
In a method for detecting the presence of cells having a specific surface membrane antigen, said method comprising: combining viable cells labelled with a vital fluorescent dye with antibodies for said surface membrane antigen and adding complement to lyse antibody bound labelled viable cells; and determining the presence of remaining labelled viable cells by their fluorescence in the substantial absence of extracellular fluorescence; the improvement which comprises removing extracellular fluorescence by adding receptors to the fluorescer which quench the extracellular fluorescence.
Claim 2
Dependent Claim
81 words
In a method for detecting the presence of cells having a specific surface membrane antigen, said method comprising: combining viable cells labelled with a vital fluorescent dye with antibodies for said surface membrane antigen and adding complement to lyse antibody bound labelled viable cells; and determining the presence of remaining labelled viable cells by their fluorescence in the substantial absence of extracellular fluorescence; the improvement which comprises removing extracellular fluorescence by adding receptors to the fluorescer which quench the extracellular fluorescence.
Claim 3
Dependent Claim
13 words
A method according to claim 1, wherein said cells are peripheral blood lymphocytes.
Claim 4
Independent Claim
18 words
A method according to any of claims 1 or 2, wherein said vital fluorescent dye is carboxy-fluorescein diacetate.
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) | 1988-07-29 | 1989-01-28 | 1989-07-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-29 | 1993-01-28 | 1993-07-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-29 | 1997-01-28 | 1997-07-30 | $7700.00 | Window Closed / Lapsed |