DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 09/01/2026 has been entered.
Priority
The present application is filed as a continuation of 15/071,626, filed 02/06/2016, which claims benefit under 35 U.S.C. 119(e) to provisional application Nos. 62/247,415, filed 10/28/2015 and 62/113,141, filed 02/06/2016.
Status of the Claims
Claims 61-69, 72-78, 82 and 123 are pending; claims 1-60, 70, 71, 79-81 and 83-122 are canceled; and no claims are amended; claims 64, 76, 77 and 82 are withdrawn. As such, claims 61-63, 65-69, 72-75, 78 and 123 are examined below.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 61-63, 65-68, 72-75 and 78 are rejected under 35 U.S.C. 103 as being unpatentable over Cho et al., Relationship between the expressions of PD-L1 and tumor-infiltrating lymphocytes in oral squamous cell carcinoma, Oral Oncology, 47, (2011), p. 1148-1153 in view of Kelly et al., US PG Pub No. 2013/0115593A1, Buchwalow et al., A multicolor fluorescence immunostaining technique for simultaneous antigen targeting, Acta Histochemica, 107, (2005), p. 143-148 and Kushculey et al., US PG Pub No. 2009/0230823A1, as evidenced by each of Keller et al., EP1103622A2 (English machine translation obtained via Google Patents), Stevens, US PG Pub No. 2001/0051380A1 and Hoffman, JP3544962B2 (English translation obtained via Google Patents).
Cho teach methods for immunological assay, the methods of Cho comprising evaluating PD-L1 expression and the infiltration degree of each lymphocyte by IHC, the IHC methods of Cho comprising the detection of a panel of three antigens, namely CD4, CD8 and PD-L1 in a tissue specimen (i.e., providing a tissue sample, and addressing Applicant’s elected species of cellular antigens for first, second and third target antigen) (see abstract and page 1149, col. 1, para 2). In particular, Cho teach reacting the first target antigen (CD4) with a first immunoreagent, the second target antigen (CD8) with a second immunoreagent, and the third target antigen (PD-L1) with a third immunoreagent (see the IHC technique of Cho comprising the use of primary specific antibodies (one specific antibody for each targeted antigen)). See Cho teach detection of primary antibodies using the Dako EnVisionTM kits (Dako) (namely labeled secondary antibody), thereby addressing reacting the first immunoreagent with a first detectable secondary antibody, the second immunoreagent with a second detectable secondary antibody, and the third immunoreagent with a third detectable secondary antibody, and detecting the first, second and third secondary detectable antibodies (see page 1149, end of col. 1 to col. 2, first, second and third antigens analyzed simultaneously, see further col. 2 results, referring to analysis of the 3 antigens detected in the tissue specimens, see further page 1150, col. 1, end of col., relationship between PD-L1 expression and CD8, CD4 expressions evaluated, i.e., analyzed).
Although Cho is disclosing indirect binding for detection of each of the antigens of the panel, Cho fails to teach the IHC method comprising primary antibodies coupled to bridging antigens, namely a first primary antibody coupled to a first bridging antigen, a second primary antibody coupled to a second bridging antigen, and a third primary antibody coupled to a third bridging antigen; and fails to teach secondary antibody for each bridging antigen (i.e., first secondary antibody for the first bridging antigen, second secondary antibody for the second bridging antigen, and third secondary antibody for the third bridging antigen). As such, Cho similarly fails to teach detectable second antibodies having high affinity for each of the respective bridging antigens. Cho et al. is also silent as to whether or not their paraffin embedded tissue is fixed tissue (see page 1149, col. 1, paras 1 and 2, specimens are paraffin-embedded tissue specimens, sectioned, deparaffinized in xylene, and rehydrated in graded alcohol solution) and further fails to clearly teach each of the first, second and third antigens reacted with the antibodies in the same tissue specimen, such that they are simultaneously analyzed/detected.
However, although Cho fails to teach the indirect binding assay format comprising primary antibody coupled a bridging antigen detected by labeled secondary antibody for the bridging antigen (see as noted above, Cho merely teach indirect binding, not this particular indirect format with bridging antigen), this indirect binding assay technique (using bridging antigen) was well known to those of ordinary skill in the art at the time, see for example Kelly discussing art recognized indirect binding techniques (paras [0084] and [0086], comprising either secondary antibody specific for primary antibody OR secondary antibody for hapten that binds haptenylated primary antibody). Kelly et al. teach kits and reagents for detection of target antigen in sample (samples including tissue), see Kelly teach for example use of haptenylated primary antibody specific for an antigen, and an anti-hapten antibody conjugated to an enzyme label (see para [0086]). See also para [0086] Kelly teach detection reagents for more than one target, e.g., multiplex detection of one or more target molecules present in a specimen such as tissue (i.e., in a single sample, see also paras [0005] and [0058] of Kelly, referencing the use of different colors to identify multiple targets on one sample).
Buchwalow review different approaches focused on multiple immunolabeling with monoclonal primary antibodies (detecting multiple antigens simultaneously), see abstract, Buchwalow teach a basic universal protocol for use of secondary antibodies that selectively recognize different monoclonal primary antibodies, that this offers a simple technique for simultaneous detection of multiple antigens. See at page 144, col. 1, para 1, Buchwalow teach methods for immunofluorescent detection of multiple tissue antigens in their simplest form make use of primary antibodies that are raised in different species and therefore can be accordingly visualized with differently labeled species-specific secondary antibody. Buchwalow teach a general problem in immunocytochemistry is the development of a reliable multiple immunolabeling method with primary antibodies originating from the same host species (abstract and page 144, col. 1, para 1 a general problem relates to the fact that most of the available primary antibodies originate from two main species, i.e., rabbit and mouse, resulting in cross reaction with the secondary species-specific antibodies). In particular, see Buchwalow teach indirect methods using haptenylated primary antibodies as an approach known to this problem (see page 145, col. 1, para 1, describing haptens, e.g., biotin, digoxigenin or any fluorophore).
Kushculey et al. teach, regarding tissue sectioning techniques, for preparing samples for histology evaluations, that the most common technique to cut fixed tissues is the paraffin-embedded tissue (PET) method. At para [0178], Kushculey et al. teach that in order to obtain thin sections, tissues must be infiltrated after fixation with embedding substances that impart a rigid consistency to the tissue, most common material being paraffin. Kushculey et al. teach formalin fixation is a crucial step prior to the embedding procedures.
Regarding hapten-anti-hapten binding reactions, see for example Keller et al. and Stevens as evidence that hapten/anti-hapten antibody interaction is considered to be a high affinity binding interaction. Keller et al., (translation, page 4, second paragraph), hapten/anti-hapten binding interaction is considered in the prior art as a high-affinity binding interaction. This is further supported by Stevens, para [0046], the high affinity binding pair system is a hapten….and a specific anti-hapten antibody. Further, see also Hoffmann, page 6, para [0024], Hoffman teach binding pairs containing haptens or hapten-like molecules exhibiting high affinity, para [0024], Hoffman indicate such affinity is at least 10-9 M, more preferable 10-10 M, most preferable 10-11 M.
It would have been prima facie obvious to one having ordinary skill in the art before the effective filing date of the claimed invention, to have modified the indirect IHC method of Cho comprising indirect detection of the panel of cellular antigen markers PD-L1, CD4 and CD8 to have substituted the indirect assay technique (binding reagents) of Cho for that of Kelly and Buchwalow, in particular to have substituted the assay binding format in order to use antigen specific haptenylated primary antibodies to target the antigens (a high affinity binding interaction, see for example as evidenced by each of Keller et al. and also Stevens), thereby modifying the method in order to achieve simultaneous detection of the primary antibodies bound at each antigen with differentially detectable anti-hapten secondary antibodies (simultaneous detection/analysis) as an obvious matter of a simple substitution of one known indirect binding format for another because both were art recognized indirect binding techniques for multiplex detection of plural antigens in a specimen (see each of Cho, Kelly and Buchwalow), one specifically motivated to modify in this way because the modification eliminates a need for multiplex detection comprising different species primary antibodies, and further one motivated to use haptenylated primary antibody and anti-hapten secondary antibody detection reagents in order to reduce instances of cross-reaction when primary antibodies are of the same species (as in Cho, see CD4 and CD8 primary antibody both comprising monoclonal mouse anti-human antibodies). Additionally, one would have been motivated to apply this technique, allowing simultaneous multiple antigen detection (consistent with Buchwalow and also Kelly), because the prior art reports this technique as a simple technique for simultaneous detection of multiple antigens.
One having ordinary skill in the art would have a reasonable expectation of success performing the modification as indicated above (the substitution of the indirect binding technique of Cho for the indirect haptenylated binding technique of Kelly and Buchwalow) because both Kelly and Buchwalow support the technique is similarly adaptable for multiple detection of differentially detectable target antigens, simultaneously.
Additionally, regarding the previous amendment to claim 61, in order to recite, “wherein the first, second and third bridging antigens are structurally distinct from one another”, it would have been obvious to one of ordinary skill from the combination as set forth in detail above, that the haptens be distinct haptens from one another (i.e., distinct structural species), such to achieve the multiplex detection. The combination of the cited art addresses this limitation because if they were not distinct, one could not achieve differential detection (i.e., if they were labeled the same, the first, second and third targets could not be distinguished). One having ordinary skill would appreciate that the combination of references as set forth above must rely on distinct hapten species because the use of haptenylated primary antibody and secondary antibody to the hapten serves the purpose of overcoming, for example, any issue that would arise using a single host species for primary antibodies (referring to Buchwalow above).
Further, based on the cited prior art above (Keller et al., and also Stevens), those having ordinary skill in the art would have recognized hapten/anti-hapten antibody binding interaction of Kelly to be a high affinity binding interaction (the anti-hapten antibody binding the hapten (i.e., bridging antigen) with high affinity). See also evidentiary reference Hoffman as cited above, which serves as further evidence to support that such hapten/anti-hapten antibody interaction is a high affinity interaction, specifically this interaction is high affinity according to what Applicant indicates in the originally filed specification to be meant by high affinity (see Hoffman teaching affinity that is 10-9-10-11 M as being high affinity binding, which is consistent with what Applicant indicates to be high affinity, at originally filed specification para [0110]).
Although Cho et al. does not specifically teach their tissue specimens are fixed tissue specimens, Cho et al. does teach tissue that is paraffin-embedded tissue sections. It would have been prima facie obvious to one having ordinary skill in the art before the effective filing date of the claimed invention that the tissue of Cho is a fixed tissue because it was known that with paraffin embedded tissue (the most common technique to cut fixed tissue sections), tissue must be infiltrated with the embedding substance after fixation, see as taught by Kushculey et al., fixation is a crucial step in the embedding procedure. Considering that prior to embedding in paraffin, tissue is commonly fixed, it would have been obvious that the tissue of Cho is a fixed tissue specimen because although Cho is silent as to whether or not their tissue is fixed, fixation was a commonly recognized, crucial step in achieving paraffin embedded sectioning of tissue.
One having ordinary skill would have a reasonable expectation of success since Cho is specifically teaching their tissue is paraffin embedded, treated by deparaffinized in xylene, and rehydrated in graded alcohol solution, the step of rehydration further supporting the specimen had been a fixed sample (and as such, subjected to dehydration).
Regarding claims 62, 63, 74 and 75, see as cited above, the combination of the cited art addresses Applicant’s elected species of panel, namely CD8, CD4 and PD-L1, each of which are cellular surface markers.
Regarding claim 65, see the art as cited in detail above, the combination of the cited art addresses wherein the first, second and third detectable secondary antibodies are each differentially detectably labeled.
Regarding claims 66, 68 and 73 see regarding multiplex indirect detection using haptenylated antibodies, see Kelly teach secondary enzyme conjugated antibody, such as alkaline phosphatase (para [0086]). It would have been further obvious to have performed the indirect detection using an enzyme label (enzymatic detection of a label such as alkaline phosphatase as in Kelly) for detection as an obvious matter of applying a known label for its art recognized purpose, namely detection of a targeted molecule/antigen. One having ordinary skill in the art would have a reasonable expectation of success using a known reagent for its art recognized intended purpose.
Regarding claims 67, 72 and 78, see further Kelly also teach at para [0057] a label is a detectable compound that can be directly or indirectly conjugated to facilitate detection, see Kelly teach examples of suitable labels include fluorescent labels, see for example fluorophores (para [0083]) are indicated as a suitable label species (in addition to enzyme labels). It would have been further obvious to have performed the indirect detection using a fluorophore label (detecting the fluorescence) for detection as an obvious matter of applying a known label for its art recognized purpose, namely detection of a targeted molecule/antigen. One having ordinary skill in the art would have had a reasonable expectation of success using a known reagent for its art recognized intended purpose.
Claims 68 and 69 are rejected under 35 U.S.C. 103 as being unpatentable over Cho in view of Kelly, Buchwalow and Kushculey et al., as evidenced by each of Keller et al., EP1103622A2 (English machine translation obtained via Google Patents), Stevens, US PG Pub No. 2001/0051380A1 and Hoffman, JP3544962B2 (English translation obtained via Google Patents), as applied to claim 66 above, and further in view of Price, US PG Pub No. 2003/0152962A1.
Cho et al. and the cited prior art teach a method substantially as claimed (see as discussed in detail above); see the cited art addresses enzyme label that is alkaline phosphatase. However, Cho and the cited prior art fails to teach wherein the enzyme label is peroxidase, particularly horseradish peroxidase (claims 68 and 69).
However, see Price for example, teaching detection of target markers in a tissue specimen (e.g., abstract), Price teach regarding secondary antibody reagent, that secondary detection antibody is preferably conjugated to either fluorescent or enzyme label, that this is conventional for indirect immunohistochemistry (para [0040]). Price teach examples of enzyme labels are HRP or alkaline phosphatase (para [0040]).
It would have been prima facie obvious to one having ordinary skill in the art before the effective filling date of the claimed invention to have substituted the enzyme label alkaline phosphatase (as in Kelly) for horseradish peroxidase as a simple substitution of one known enzyme for indirect detection for another. In particular, the prior art recognized indirect detection using enzyme labeled secondary antibody (see e.g., Cho, Kelly, Price). Further, each of the specific species of enzyme, alkaline phosphatase (Kelly and Price) and horseradish peroxidase (Price), were art recognized enzymes, both known for indirect binding assay (Price, Price teaching enzyme label as conventional label for indirect IHC, specifically indicating both of these enzymes as specific examples). Given this knowledge recognized by those of ordinary skill in the art, one having ordinary skill would have found it obvious to have substituted one known enzyme for the other, and the results of the substitution would have been predictable, namely it would be predictable that indirect detection would be achieved (it would be predictable that the enzymes would be interchangeable considering both were recognized for this art recognized purpose).
The ordinarily skilled artisan would have a reasonable expectation of success considering such enzymatic detection was considered conventional in the assay art for indirect detection (Price).
Claim 123 is rejected under 35 U.S.C. 103 as being unpatentable over Cho et al. in view of Kelly et al., Buchwalow et al., and Kushculey et al, as evidenced by each of Keller et al., Stevens, and Hoffman, as applied to claim 61 above, and further in view of Williamson et al., US PG Pub No. 2014/0363427A1 and Tanenbaum et al., A protein tagged system for signal amplification in gene expression and fluorescence imaging, Cell, 159(3), (2014), p. 635-646 (IDS entered 01/07/2021).
Cho et al. and the cited prior art teach a method substantially as claimed (see as discussed in detail above, the combination of the cited art teaching the use of hapten at the primary antibody (haptenylated primary antibody) and a secondary antibody specific to said hapten, using different haptens (each having a single molecular structure, i.e., distinct species) at each primary antibody); however, the combination of the cited prior art fails to teach each single molecular structure as having a plurality of antigenic determinants (claim 123).
As discussed in detail previously above, Buchwalow teach using a bridging sequence (hapten) between the primary antibody, to which secondary antibody binds (hapten that serves as a bridging antigen, see as discussed in detail above).
See also Williamson et al., Williamson also recognize that primary antibody epitope tagging was known in the prior art, see for example described at para [0206], Williamson teach a tag/epitope tag referring to a sequence of amino acid residues added to, for example, an antibody, the use of such tag for purpose including detection. Williamson et al. (para [0206]) teach a tag comprising a polypeptide with enough residues to provide an epitope recognized by an antibody, yet short enough such that it does not interfere with activity to that which it is attached, tag polypeptide is typically sufficiently unique so an antibody that specifically binds thereto does not substantially cross-react with epitopes in in the polypeptide to which it is linked, that such tags are well-known and can be readily synthesized and designed.
Tanenbaum et al. teach, with regard to peptide tags comprising repeating sequences, that such tags are capable of recruiting multiple detectably labeled antibodies (see abstract, page 3, paragraph 2, and Figure 1), thereby amplifying signal (e.g., title and abstract, see also page 10, para 3). See at figure 1, multiple labeled antibodies are able to bind at the tandem repeating structures.
It would have been prima facie obvious to one having ordinary skill in the art, to have modified Cho and the cited prior art in order to modify the haptenylated primary antibodies, to instead using peptide tags (and secondary antibody specific to each tag), as in Williamson, as a simple substitution of one art recognized antigen for bridging binding between primary and secondary antibody for another (hapten, as in Buchwalow for polypeptide sequence, as in Williamson et al.). In particular, the base concept was recognized in the prior art (indirect binding achieved by an antigen bound to a primary antibody, secondary antibody binding that antigen), see for example either of Buchwalow (and further supported by Williamson), either species of antigen (hapten or polypeptide, with secondary antibody specific to said hapten or polypeptide) was known in the prior art (Buchwalow and Williamson). One having ordinary skill in the art would have found it obvious to have used a polypeptide antigen (tag) in place of hapten, and the results would have been predictable because both are similarly used in the same way (see referring to citation of each above).
Regarding the modification to use a polypeptide sequence, it would have been further obvious to have modified the peptides with the type or repeating tag structure as in Tanenbaum, namely comprising multiple repeating structures, in order to recruit a plurality of labeled detection antibodies, as in Tanenbaum, in order to amplify signal, thereby improving detection. One having ordinary skill in the art would have a reasonable expectation of success modifying in this way because it was known in the art to use peptide tags to facilitate binding between primary and secondary antibody (polypeptide tagged primary antibody, detectable using labeled secondary antibody, Williamson).
Response to Arguments
Applicant's arguments filed 09/01/2026 have been fully considered but they are not persuasive for the following reasons:
Applicant argues the rejection of claims under 35 U.S.C. 103 (see remarks pages 7-8), specifically Applicant maintains previous arguments of record (page 7), Applicant remarks on limitations missing from Cho et al. (does not teach bridging antigen, and secondary antibody having high affinity for bridging antigens, and does not explicitly disclose the sample is fixed). Applicant argues the additionally cited references, and the three evidentiary references, do not teach any multiplexed tissue assay. Applicant argues that the reasons to combine and the asserted expectations of success rest on the cited combination rather than on evidence contemporaneous with the effective filing date.
It is maintained that Applicant’s previous arguments are not persuasive for the reasons discussed previously (previous response to argument), and further contrary to Applicant’s argument that none of the additionally cited references teach any multiplex tissue assay, it is noted that Cho et al. is teaching multiplexed detection in a tissue specimen. See also cited in detail above Buchwalow is teaching multiple antigens detected in a tissue specimen. Furthermore, the citation of Kelly et al. above is also in reference to multiplex detection of multiple targeted analytes in a tissue specimen, referring to para [0086] cited above).
Applicant remarks that the reason to combine and expectation of success rest on the recited combination of references rather than on evidence contemporaneous with the effective filing date, however, no specific evidence against the cited combination of references is presented in the present remarks.
For all of these reasons, Applicant’s remarks are not persuasive and the rejections are maintained.
Conclusion
All claims are identical to or patentably indistinct from, or have unity of invention with claims in the application prior to the entry of the submission under 37 CFR 1.114 (that is, restriction (including a lack of unity of invention) would not be proper) and all claims could have been finally rejected on the grounds and art of record in the next Office action if they had been entered in the application prior to entry under 37 CFR 1.114. Accordingly, THIS ACTION IS MADE FINAL even though it is a first action after the filing of a request for continued examination and the submission under 37 CFR 1.114. See MPEP § 706.07(b). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Correspondence
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ELLEN J MARCSISIN whose telephone number is (571)272-6001. The examiner can normally be reached M-F 8:00am-4:30pm.
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/ELLEN J MARCSISIN/Primary Examiner, Art Unit 1677
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