Patent US4487839A successfully refreshed from Google Patents.
US4487839A
Expired / Lapsed
US
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Immunoassay methods employing patterns for the detection of soluble and cell surface antigens
Assignee: Ortho Clinical Diagnostics Inc
•
Filing: 1983-01-05
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Granted: 1984-12-11
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Expires: 2003-01-05
Abstract
Abstract Methods for determining the presence of antigens or antibodies in an aqueous sample or presence of antigens on the surface of cells. A preferred embodiment employs fluorescent antigens which compete with the sample antigens for antibody binding sites. The antibodies are deposited on a support surface means in alternating patterns. The surface means and fluorescence detector are translocated with respect to each other and a signal generated by the detection of the repeating pattern of fluorescence. The signal is analyzed by means of a gated integrator responsive to a gate track control means also located on the surface means. Immunoassay methods having increased sensitivity are thereby obtained.
Inventors
- 👤 Louis A. Kamentsky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:36
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/8483; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/543; G01N33/54366; G01N33/569; G01N33/56966; G01N33/80; Y; Y10; Y10S; Y10S436/00; Y10S436/80; Y10S436/804; Y10S436/807; Y10S436/808; Y10S436/809; Y10S436/823
Claims Analysis
Total Claims: 69
Claim 1
Independent Claim
253 words
A method for determining the presence of antigens in an aqueous sample comprising the steps of: (a) providing surface means having first antibodies, specific for the antigens to be determined, associated therewith in a specified pattern of areas, each area alternating with the presence and absence of said first antibodies; (b) further providing an aqueous solution containing a known quantity of labeled antigens having substantially the same reactivity with said first antibodies as the antigens to be determined; (c) contacting the aqueous sample and the aqueous solution with said surface means under conditions appropriate for permitting an immunological reaction to occur whereby said labeled and sample antigens compete for binding sites on said first antibodies; (d) illuminating at least one first area having first antibodies associated therewith and detecting the effect of said illumination on said label associated with said area by detection means for providing a first signal responsive to the presence of said labeled antigens; (e) translocating said surface means with respect to said detector means and further illuminating at least one second area having an absence of first antibodies associated therewith and detecting the effect of said illumination on said label associated with said area whereby a second signal responsive to the presence of said labeled antigens is provided; and (f) analyzing said first and second signals whereby the presence of antigens in said aqueous sample may be determined based on the relative absence or presence of bound labeled antigen in said first area in comparison to said second area.
Claim 2
Independent Claim
253 words
A method for determining the presence of antigens in an aqueous sample comprising the steps of: (a) providing surface means having first antibodies, specific for the antigens to be determined, associated therewith in a specified pattern of areas, each area alternating with the presence and absence of said first antibodies; (b) further providing an aqueous solution containing a known quantity of labeled antigens having substantially the same reactivity with said first antibodies as the antigens to be determined; (c) contacting the aqueous sample and the aqueous solution with said surface means under conditions appropriate for permitting an immunological reaction to occur whereby said labeled and sample antigens compete for binding sites on said first antibodies; (d) illuminating at least one first area having first antibodies associated therewith and detecting the effect of said illumination on said label associated with said area by detection means for providing a first signal responsive to the presence of said labeled antigens; (e) translocating said surface means with respect to said detector means and further illuminating at least one second area having an absence of first antibodies associated therewith and detecting the effect of said illumination on said label associated with said area whereby a second signal responsive to the presence of said labeled antigens is provided; and (f) analyzing said first and second signals whereby the presence of antigens in said aqueous sample may be determined based on the relative absence or presence of bound labeled antigen in said first area in comparison to said second area.
Claim 3
Dependent Claim
66 words
The method as provided in claim 1 wherein said providing step comprises providing surface means further comprising gate track control means, corresponding to the patterned areas of antibody presence and absence on said surface means, and said analyzing step further comprises detecting said gate track control means for enabling the analyzing step by associating said first and second signals with said first and second areas respectively.
Claim 4
Dependent Claim
63 words
The method as provided in claim 2 wherein the analyzing step comprises processing said first and second signals with gated integrator means whereby detecting said gate track control means enables said gated integrator means to positively integrate said first signals and negatively integrate said second signals from said detection means whereby the presence of said antigen in said aqueous sample may be determined.
Claim 5
Dependent Claim
45 words
The method as provided in claim 3 wherein said illuminating step comprises illuminating a fluorescent dye label at a light frequency which causes the label to fluoresce, and the step of detecting the effect of said illumination comprises detecting bulk fluorescence associated with said label.
Claim 6
Dependent Claim
40 words
The method as provided in claim 4 further comprising the step of removing said antigens to be determined and said labeled antigens which have not reacted immunologically with said first antibodies on said surface means by washing said surface means.
Claim 7
Dependent Claim
21 words
The method as provided in claim 3 wherein the step of detecting the effect of said illumination comprises detecting bulk fluorescence.
Claim 8
Dependent Claim
22 words
The method as provided in claim 1 wherein said providing step comprises providing a generally rectangular tape adapted for substantially linear motion.
Claim 9
Independent Claim
188 words
A method for determining within a sample the presence of cells having a specified surface antigen, comprising the steps of: (a) providing surface means having a pattern of areas alternating with the presence and absence of first antibodies associated therewith and specific for the surface antigens to be determined; (b) contacting said sample containing the cells with said surface means under conditions appropriate to allow an immunological reaction to occur; (c) staining the cells which have immunologically reacted with a detectable label; (d) illuminating said surface means and detecting the effect of said illumination whereby a first signal responsive to the presence of said label in an area having antibodies associated therewith is generated; (e) further illuminating said surface means and further detecting the effect of said illumination whereby a second signal responsive to the presence of said label in an area having an absence of antibodies associated therewith is generated; and (f) analyzing said first and second signals and determining the presence of cells having a specific surface antigen based on the association of said label with said area having antibodies specific for said cellular surface antigen.
Claim 10
Independent Claim
188 words
A method for determining within a sample the presence of cells having a specified surface antigen, comprising the steps of: (a) providing surface means having a pattern of areas alternating with the presence and absence of first antibodies associated therewith and specific for the surface antigens to be determined; (b) contacting said sample containing the cells with said surface means under conditions appropriate to allow an immunological reaction to occur; (c) staining the cells which have immunologically reacted with a detectable label; (d) illuminating said surface means and detecting the effect of said illumination whereby a first signal responsive to the presence of said label in an area having antibodies associated therewith is generated; (e) further illuminating said surface means and further detecting the effect of said illumination whereby a second signal responsive to the presence of said label in an area having an absence of antibodies associated therewith is generated; and (f) analyzing said first and second signals and determining the presence of cells having a specific surface antigen based on the association of said label with said area having antibodies specific for said cellular surface antigen.
Claim 11
Dependent Claim
27 words
The method as provided in claim 8 wherein the step of staining the cells is accomplished by applying to the cells an effective solution of fluorescein diacetate.
Claim 12
Dependent Claim
20 words
The method as provided in claim 8 further comprising the step of removing unbound cells prior to the detecting steps.
Claim 13
Dependent Claim
58 words
The method as provided in claim 8 wherein said analyzing step is enabled by additionally detecting gate track control means associated with said surface means and corresponding to the pattern of antibody presence and absence on said surface means whereby said first and second signals are identified with areas of presence and absence of said first antibodies respectively.
Claim 14
Dependent Claim
58 words
The method as provided in claim 10 wherein said analyzing step is enabled by additionally detecting gate track control means associated with said surface means and corresponding to the pattern of antibody presence and absence on said surface means whereby said first and second signals are identified with areas of presence and absence of said first antibodies respectively.
Claim 15
Dependent Claim
43 words
The method as provided in claim 11 wherein based on detecting said gate track control means said analyzing step comprises processing said first and second signals with gated integrator means whereby the presence of cells containing the specified surface antigen may be determined.
Claim 16
Dependent Claim
43 words
The method as provided in claim 12 wherein based on detecting said gate track control means said analyzing step comprises processing said first and second signals with gated integrator means whereby the presence of cells containing the specified surface antigen may be determined.
Claim 17
Dependent Claim
67 words
The method as provided in claim 8 further comprising detecting gate track control means associated with said surface means and corresponding to the pattern of antibody presence and absence on said surface means for controlling gated integrator means whereby said first detected signals are integrated positively and said second detected signals are integrated negatively and the presence of cells containing the specified surface antigen may be determined.
Claim 18
Independent Claim
201 words
A method for determining the presence of cells having a specified surface antigen, said cells present within a sample, comprising the steps of: (a) providing surface means having second antigens applied thereto in a specified pattern of areas alternating with the presence and absence of said second antigens; (b) providing an antibody-complex specific for the specified cell surface antigen and for the second antigen whereby, after allowing an immunological reaction between said antibody-complex, said cell, and said second antigen, an antibody bridge between the surface means and the cells may be formed; (c) permitting, under appropriate conditions, said immunological reaction to occur; (d) staining the cells with a detectable label; (e) illuminating an area of said surface means having second antigens present and detecting the effect of said illuminatination on said labeled cells whereby a first signal responsive to the presence of label is generated; (f) illuminating an area of said surface means having second antigens absent and detecting the effect of said illumination on said labeled cells whereby a second signal responsive to the presence of label is generated; and (g) analyzing said first and second signals whereby the presence of cells having a specified surface antigen may be determined.
Claim 19
Independent Claim
201 words
A method for determining the presence of cells having a specified surface antigen, said cells present within a sample, comprising the steps of: (a) providing surface means having second antigens applied thereto in a specified pattern of areas alternating with the presence and absence of said second antigens; (b) providing an antibody-complex specific for the specified cell surface antigen and for the second antigen whereby, after allowing an immunological reaction between said antibody-complex, said cell, and said second antigen, an antibody bridge between the surface means and the cells may be formed; (c) permitting, under appropriate conditions, said immunological reaction to occur; (d) staining the cells with a detectable label; (e) illuminating an area of said surface means having second antigens present and detecting the effect of said illuminatination on said labeled cells whereby a first signal responsive to the presence of label is generated; (f) illuminating an area of said surface means having second antigens absent and detecting the effect of said illumination on said labeled cells whereby a second signal responsive to the presence of label is generated; and (g) analyzing said first and second signals whereby the presence of cells having a specified surface antigen may be determined.
Claim 20
Dependent Claim
26 words
The method as provided in claim 16 wherein the step of staining the cells is accomplished by applying to the cells a solution of fluorescein diacetate.
Claim 21
Dependent Claim
21 words
The method as provided in claim 16 further comprising the step of removing unbound cells prior to the label detecting steps.
Claim 22
Dependent Claim
70 words
The method as provided in claim 16 wherein said providing step comprises providing surface means having gate track control means corresponding to the patterned areas of antigen presence and absence on said surface means, and said analyzing step further comprises detecting said gate track control means for enabling the analyzing step by identifying said first and second signals with said areas having a presence and absence of second antigens respectively.
Claim 23
Dependent Claim
70 words
The method as provided in claim 18 wherein said providing step comprises providing surface means having gate track control means corresponding to the patterned areas of antigen presence and absence on said surface means, and said analyzing step further comprises detecting said gate track control means for enabling the analyzing step by identifying said first and second signals with said areas having a presence and absence of second antigens respectively.
Claim 24
Dependent Claim
57 words
The method as provided in claim 19 wherein said analyzing step comprises processing said first and second signals with gated integrator means in response to said gate track control means whereby said first signals are integrated positively and said second signals are integrated negatively and the presence of cells containing the specified surface antigen may be determined.
Claim 25
Dependent Claim
57 words
The method as provided in claim 20 wherein said analyzing step comprises processing said first and second signals with gated integrator means in response to said gate track control means whereby said first signals are integrated positively and said second signals are integrated negatively and the presence of cells containing the specified surface antigen may be determined.
Claim 26
Independent Claim
236 words
A method for determining the presence of antigens in an aqueous sample comprising the steps of: (a) providing first antibodies and surface means having second antigens with substantially the same immunological reactivity with said first antibodies as the antigens to be determined, said second antigens associated with said surface in a specified pattern of areas, each area of presence alternating with an area of absence of said second antigens; (b) immunologically reacting substantially all said second antigens with said first antibodies and removing substantially all unbound first antibodies; (c) contacting the aqueous sample with said surface means under conditions appropriate for permitting an immunological reaction to occur whereby said antigens to be determined may be bound to said first antibodies; (d) further providing an aqueous solution containing second labeled antibodies immunologically reactive with said antigens to be determined under conditions appropriate for permitting an immunological reaction to occur whereby said second labeled antibodies may be bound to said antigens to be determined if present; (e) illuminating an area of said surface means having second antigens present and detecting the presence of said label whereby a first signal is generated; (f) illuminating an area of said surface means having an absence of second antigens and detecting the presence of said label whereby a second signal is generated; and (g) analyzing said first and second signals whereby the presence of antigens in said aqueous sample may be determined.
Claim 27
Independent Claim
236 words
A method for determining the presence of antigens in an aqueous sample comprising the steps of: (a) providing first antibodies and surface means having second antigens with substantially the same immunological reactivity with said first antibodies as the antigens to be determined, said second antigens associated with said surface in a specified pattern of areas, each area of presence alternating with an area of absence of said second antigens; (b) immunologically reacting substantially all said second antigens with said first antibodies and removing substantially all unbound first antibodies; (c) contacting the aqueous sample with said surface means under conditions appropriate for permitting an immunological reaction to occur whereby said antigens to be determined may be bound to said first antibodies; (d) further providing an aqueous solution containing second labeled antibodies immunologically reactive with said antigens to be determined under conditions appropriate for permitting an immunological reaction to occur whereby said second labeled antibodies may be bound to said antigens to be determined if present; (e) illuminating an area of said surface means having second antigens present and detecting the presence of said label whereby a first signal is generated; (f) illuminating an area of said surface means having an absence of second antigens and detecting the presence of said label whereby a second signal is generated; and (g) analyzing said first and second signals whereby the presence of antigens in said aqueous sample may be determined.
Claim 28
Dependent Claim
43 words
The method as provided in claim 23 further comprising the step of detecting gate track control means associated with said surface means and corresponding to the pattern of second antigen presence and absence on said surface means and for enabling the analyzing step.
Claim 29
Dependent Claim
56 words
The method as provided in claim 24 wherein the analyzing step comprises processing said first and second signals with gated integrator means based on said gate track control means whereby said first signals are integrated positively and said second signals are integrated negatively whereby the presence of said antigen in said aqueous sample may be determined.
Claim 30
Dependent Claim
55 words
The method as provided in claim 25 wherein the further providing step comprises providing second antibodies labeled with a fluorescent dye, said illuminating steps comprise illuminating at a frequency of light which causes the label to fluoresce, and the step of detecting the effect of said illumination comprises detecting bulk fluorescence associated with said label.
Claim 31
Dependent Claim
34 words
The method as provided in claim 26 further comprising the step of removing, prior to said illuminating step, substantially all unbound second labeled antibodies which have not reacted immunologically by washing said surface means.
Claim 32
Dependent Claim
21 words
The method as provided in claim 26 wherein the step of detecting the effect of said illumination comprises detecting bulk fluorescence.
Claim 33
Dependent Claim
25 words
The method as provided in claim 23 wherein said providing step comprises providing surface means comprising a generally rectangular tape adapted for substantially linear motion.
Claim 34
Independent Claim
229 words
A method for determining the presence of antigens in an aqueous sample comprising the steps of: (a) providing surface means having first antibodies specific for a first epitopic site on said antigens to be determined, and which are associated with said surface in a specified pattern of areas, each area alternating with the presence and absence of said first antibodies; (b) contacting the aqueous sample with said surface means under conditions appropriate for permitting an immunological reaction to occur whereby said antigens to be determined may be bound to said first antibodies; (c) further providing an aqueous solution containing second labeled antibodies immunologically reactive with a second epitopic site on said antigens to be determined under conditions appropriate for permitting an immunological reaction to occur whereby said second labeled antibodies may be bound to said antigens to be determined if present; (d) illuminating an area having said first antibodies present and detecting the effect of said illumination on said label whereby a first signal responsive to the presence of said labeled antibodies is provided; (e) illuminating an area having an absence of said first antibodies and detecting the effect of said illumination on said label whereby a second signal responsive to the presence of said labeled antibodies is provided; and (f) analyzing said first and second signals whereby the presence of antigens in said aqueous sample may be determined.
Claim 35
Independent Claim
229 words
A method for determining the presence of antigens in an aqueous sample comprising the steps of: (a) providing surface means having first antibodies specific for a first epitopic site on said antigens to be determined, and which are associated with said surface in a specified pattern of areas, each area alternating with the presence and absence of said first antibodies; (b) contacting the aqueous sample with said surface means under conditions appropriate for permitting an immunological reaction to occur whereby said antigens to be determined may be bound to said first antibodies; (c) further providing an aqueous solution containing second labeled antibodies immunologically reactive with a second epitopic site on said antigens to be determined under conditions appropriate for permitting an immunological reaction to occur whereby said second labeled antibodies may be bound to said antigens to be determined if present; (d) illuminating an area having said first antibodies present and detecting the effect of said illumination on said label whereby a first signal responsive to the presence of said labeled antibodies is provided; (e) illuminating an area having an absence of said first antibodies and detecting the effect of said illumination on said label whereby a second signal responsive to the presence of said labeled antibodies is provided; and (f) analyzing said first and second signals whereby the presence of antigens in said aqueous sample may be determined.
Claim 36
Dependent Claim
40 words
The method as provided in claim 30 further comprising detecting gate track control means associated with said surface means and corresponding to the pattern of said first antibody presence and absence on said surface means for enabling the analyzing step.
Claim 37
Dependent Claim
50 words
The method as provided in claim 30 wherein the analyzing step comprises processing said first and second signals with gated integrator means said integrator being gated in response to the detection of said gate track control means whereby the presence of said antigen in said aqueous sample may be determined.
Claim 38
Dependent Claim
55 words
The method as provided in claim 32 wherein the further providing step comprises providing second antibodies labeled with a fluorescent dye, said illuminating steps comprise illuminating at a frequency of light which causes the label to fluoresce, and the step of detecting the effect of said illumination comprises detecting bulk fluorescence associated with said label.
Claim 39
Dependent Claim
34 words
The method as provided in claim 33 further comprising the step of removing, prior to said illuminating steps, substantially all unbound second labeled antibodies which have not reacted immunologically by washing said surface means.
Claim 40
Dependent Claim
21 words
The method as provided in claim 33 wherein the step of detecting the effect of said illumination comprises detecting bulk fluorescence.
Claim 41
Dependent Claim
25 words
The method as provided in claim 30 wherein said providing step comprises providing surface means comprising a generally rectangular tape adapted for substantially linear motion.
Claim 42
Dependent Claim
40 words
The method as provided in claim 4 further comprising the step of removing said antigens to be determined and said labeled antigens which have not reacted immunologically with said first antibodies on said surface means by spraying said surface means.
Claim 43
Dependent Claim
42 words
The method as provided in claim 4 further comprising the step of removing said antigens to be determined and said labeled antigens which have not reacted immunologically with said first antibodies on said surface means by washing and spraying said surface means.
Claim 44
Dependent Claim
25 words
The method as provided in claim 3 wherein the step of detecting the effect of said illumination comprises detecting light reflected from said surface means.
Claim 45
Dependent Claim
25 words
The method as provided in claim 3 wherein the step of detecting the effect of said illumination comprises detecting light transmitted through said surface means.
Claim 46
Dependent Claim
43 words
The method as provided in claim 3 wherein the step of detecting the effect of said illumination comprises detecting bulk fluorescence and intrinsic fluorescence of said surface means for use as a reference whereby the true level of bulk fluorescence may be assessed.
Claim 47
Dependent Claim
39 words
The method as provided in claim 3 wherein the step of detecting the effect of said illumination comprises detecting a first fluorescent dye specifically attached to said antibodies and a second fluorescent dye nonspecifically attached to said labeled antigens.
Claim 48
Dependent Claim
19 words
The method as provided in claim 1 wherein said providing step comprises providing a disk adapted for rotary motion.
Claim 49
Dependent Claim
20 words
The method as provided in claim 1 wherein said providing step comprises providing a photoslide adapted for substantially complete illumination.
Claim 50
Dependent Claim
27 words
The method as provided in claim 44 further comprising detecting the effect of illumination by sequentially detecting portions substantially smaller than the total area of said photoslide.
Claim 51
Dependent Claim
34 words
The method as provided in claim 26 further comprising the step of removing, prior to said illuminating step, substantially all unbound second labeled antibodies which have not reacted immunologically by spraying said surface means.
Claim 52
Dependent Claim
36 words
The method as provided in claim 26 further comprising the step of removing, prior to said illuminating step, substantially all unbound second labeled antibodies which have not reacted immunologically by washing and spraying said surface means.
Claim 53
Dependent Claim
25 words
The method as provided in claim 26 wherein the step of detecting the effect of said illumination comprises detecting light reflected from said surface means.
Claim 54
Dependent Claim
43 words
The method as provided in claim 26 wherein the step of detecting the effect of said illumination comprises detecting bulk fluorescence and intrinsic fluorescence of said surface means for use as a reference whereby the true level of bulk fluorescence may be assessed.
Claim 55
Dependent Claim
33 words
The method as provided in claim 26 wherein the step of detecting the effect of said illumination comprises a combination of detecting light scatter, bulk fluorescence, and intrinsic fluorescence of said surface means.
Claim 56
Dependent Claim
22 words
The method as provided in claim 23 wherein said providing step comprises providing surface means comprising a disk adapted for rotary motion.
Claim 57
Dependent Claim
41 words
The method as provided in claim 23 wherein said providing step comprises providing surface means comprising a photoslide, and said detecting the effect of illumination comprises sequentially detecting portions of said photoslide substantially smaller than the total area of said photoslide.
Claim 58
Dependent Claim
34 words
The method as provided in claim 33 further comprising the step of removing, prior to said illuminating steps, substantially all unbound second labeled antibodies which have not reacted immunologically by spraying said surface means.
Claim 59
Dependent Claim
36 words
The method as provided in claim 33 further comprising the step of removing, prior to said illuminating steps, substantially all unbound second labeled antibodies which have not reacted immunologically by washing and spraying said surface means.
Claim 60
Dependent Claim
25 words
The method as provided in claim 33 wherein the step of detecting the effect of said illumination comprises detecting light reflected from said surface means.
Claim 61
Dependent Claim
25 words
The method as provided in claim 33 wherein the step of detecting the effect of said illumination comprises detecting light transmitted through said surface means.
Claim 62
Dependent Claim
43 words
The method as provided in claim 33 wherein the step of detecting the effect of said illumination comprises detecting bulk fluorescence and intrinsic fluorescence of said surface means for use as a reference whereby the true level of bulk fluorescence may be assessed.
Claim 63
Dependent Claim
26 words
The method as provided in claim 33 wherein the step of detecting the effect of said illumination comprises detecting bulk fluorescence reflected from said surface means.
Claim 64
Dependent Claim
22 words
The method as provided in claim 30 wherein said providing step comprises providing surface means comprising a disk adapted for rotary motion.
Claim 65
Dependent Claim
58 words
The method as provided in claim 1 wherein the providing step comprises providing surface means having first antibodies specific for the antigen to be determined, said first antibodies attached to latex particles and said particles associated with said surface means in a specified pattern of areas, each area alternating with the presence and absence of said first antibodies.
Claim 66
Dependent Claim
58 words
The method as provided in claim 8 wherein the providing step comprises providing surface means having first antibodies specific for the antigens to be determined, said first antibodies attached to latex particles and said particles associated with said surface means in a specified pattern of areas, each area alternating with the presence and absence of said first antibodies.
Claim 67
Dependent Claim
51 words
The method as provided in claim 16 wherein the providing step comprises providing surface means having second antigens, said second antigens attached to latex particles and said particles associated with said surface means in a specified pattern of areas, each area alternating with the presence and absence of said second antigen.
Claim 68
Dependent Claim
51 words
The method as provided in claim 23 wherein the providing step comprises providing surface means having second antigens, said second antigens attached to latex particles and said particles associated with said surface means in a specified pattern of areas, each area alternating with the presence and absence of said second antigens.
Claim 69
Dependent Claim
51 words
The method as provided in claim 30 wherein the providing step comprises providing surface means having first antibodies, said first antibodies attached to latex particles and said particles associated with said surface means in a specified pattern of areas, each area alternating with the presence and absence of said first antibodies.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
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| 3.5 Years (Year 4) | 1987-12-11 | 1988-06-11 | 1988-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-11 | 1992-06-11 | 1992-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-11 | 1996-06-11 | 1996-12-11 | $7700.00 | Window Closed / Lapsed |