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 .
DETAILED OFFICE ACTION
This Office Action is in response to the papers filed on 16 September 2025.
CLAIMS UNDER EXAMINATION
Claims 1, 5-7 and 21-23 have been examined on their merits.
PRIORITY
Foreign priority document SG10201600290W, filed on 14 June 2016, is acknowledged.
The foreign priority document does not provide support for proteins determined by BLAST algorithm. The earliest support for this limitation is PCTSG2017/050020 filed on 16 January 2017. The foreign priority document does not provide support for all of the claimed protein units, e.g. AFtn, AfFtn-AA, Vault, lumazine synthase and DNA-binding protein from starved cells, recited in claim 1. The foreign priority document does not provide support for all of the species of oils recited in claim 6 (e.g., mineral oils and vegetable oils) or the limitations recited in claims 8-10.
WITHDRAWN REJECTIONS
The rejection of claims 9-10, 12, 17, 19 and 22 under 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, 4th paragraph, has been withdrawn due to claim cancellation.
REJECTIONS
The previous rejections have been modified to address the amended claims.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1, 5-7 and 21-23 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement.
The claims contain subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for pre-AIA the inventor(s), at the time the application was filed, had possession of the claimed invention.
The claims recite variants that have at least 80% sequence similarity (or alternatively at least 90%) to the amino acid sequences set forth in SEQ ID Nos 1-4. However, the specification has failed to sufficiently describe the structural features that must be retained by members of the claimed genus as to establish a structure-function relationship with respect to E2, E2LC2, AfFtn and AfFtn-AA. The specification does not define the term “similarity”. The term “similarity” is defined as “resembling without being identical”. SEQ ID: 1 is 260 amino acids long. SEQ ID: 2 is 260 amino acids long. SEQ ID: 3 is 173 amino acids long. SEQ ID: 4 is 170 amino acids long. The claim language encompasses substitutions, deletions or additions in any combinations along any length of the claimed polypeptides. The use of the term “similarity” does not require any of the amino acids of a variant to be the same as the filed SEQ IDs. While the claims are drawn to a genus that comprises an infinite number of sequences, the specification has only adequately described and successfully reduced to practice the full-length of SEQ ID NO: 1-4 as filed. This is not representative of the extremely large genus of possible sequences claimed, since no variants of SEQ ID NO: 1-4 are demonstrated to form Pickering emulsions.
At best, the specification contemplates the use of BLAST to identify homologs
based on sequence homology. However, this is not sufficient to describe members of the claimed genus because such methods access online databases that are continually being updated as sequencing technology improves. As a result, they are not a static source of information. Thus, one of skill in the art would readily appreciate that relying on a non-patent source that is continuously subject to change as a means to identify members of the claimed genus does not sufficiently meet the written description requirement.
Moreover, Friedberg (Automated protein function prediction—the genomic challenge.
Brief. Bioinformatics (2006) 7: 225-242) teaches that homology based transfer is not reliable for functional annotation even with high alignment percentages (page 227, second column). Friedberg also teaches that identification of functionally significant sub-regions is critical to functional annotation, and that often addition, deletion, or re-shuffling of domains can lead to errors in annotation (page 227, second column, page 228, first paragraph). Furthermore, Friedberg teaches that sequence-based tools are just not sensitive enough to identify functional protein similarity as databases get larger, and diversity of sequences gets larger (page 228, first full paragraph).
Thornton et al. (Nature structural biology, structural genomics supplement, November
2000, pgs. 991-994) teaches that the same protein structure is often seen in apparently different homologous families with different functions. Thornton et al. further describe examples of little correlation between specific enzyme function and overall protein structure (see page 992, right column, at lines 2-10).
Thus, when taken with the teachings of Friedberg and Thornton, one of
skill in the art would readily appreciate that sequence homology alone cannot serve as the basis to describe members of the genus that have the recited function.
In the absence of a representative number of examples, the specification must at least
describe the structural features that are required for the claimed function, in this case to form Pickering emulsion protein cages.
However, as discussed above, the specification fails to describe any structural limitations as to establish a structure-function relationship with respect to the claimed variants. Instead, Applicant merely offers a cursory statement that any polypeptide similar to the claimed proteins will work. Accordingly, the claims as currently written are not adequately described and one of skill in the art would readily appreciate that Applicant was not in possession of the claimed genus at the time of filing.
A consideration of the four corners of the specification does not reflect that applicants have actually invented the claimed invention, since the specification does not permit the skilled artisan to visualize or recognize all of the members of the genus being utilized in the claimed emulsion.
RESPONSE TO APPLICANT’S ARGUMENTS
The arguments made in the response filed on 16 September 2025 are acknowledged. The arguments state the base claims have been amended to recite variants with at least 80% sequence similarity as determined by BLAST algorithm. Claim 1 has also been amended to recite the protein cage has amphiphilic properties. The Applicant argues this is sufficient to identify all possible variants that meet the claim limitations.
In response: The claims do not require 80% sequence identity to SEQ ID 1-4. The claims encompass all known and unknown proteins that are at least 80% similar to SEQ ID 1-4. As set forth in the rejection made under 35 USC 112b, the metes and bounds of the term “similar” are unclear. While there is support for the use of a BLAST algorithm, the specification does not provide support for all of the possible proteins that are at least 80% similar to sequence identities 1-4 that have the claimed properties encompassed by the claims. The specification has only adequately described and successfully reduced to practice the full-length of SEQ ID NO: 1-4. The arguments are not persuasive.
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1, 5-7 and 21-23 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 1 recites “wherein said variants have at least 80% sequence similarity to the amino acid sequences set forth in SEQ ID Nos 1-4”. The specification does not provide an explicit definition for the term “similarity”. The term “similarity” is defined as “resembling without being identical”. Therefore it is a relative term which renders the claim indefinite. The term “similarity” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. Appropriate correction is required. All dependent claims are included in this rejection. For the purpose of examination, any E2, E2LC2 or ferritin is interpreted to read on the claim.
Claim 22 recites “said variants have at least 80% sequence similarity to the amino acid sequences set forth in SEQ ID Nos 3-4”. The specification does not provide an explicit definition for the term “similarity”. The term “similarity” is defined as “resembling without being identical”. Therefore it is relative term which renders the claim indefinite. The term “similarity” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. Appropriate correction is required. All dependent claims are included in this rejection. For the purpose of examination, any ferritin is interpreted to read on the claim
Claim 23 recites “said variants have at least 90% sequence similarity to the amino acid sequences set forth in SEQ ID Nos 1-4”. The specification does not provide an explicit definition for the term “similarity”. The term “similarity” is defined as “resembling without being identical”. Therefore it is relative term which renders the claim indefinite. The term “similarity” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. Appropriate correction is required. All dependent claims are included in this rejection. For the purpose of examination, any E2, E2LC2 or ferritin is interpreted to read on the claim
RESPONSE TO APPLICANT’S ARGUMENTS
The arguments made in the response filed on 16 September 2025 are acknowledged. The Applicant argues the specification defines the term “similarity” in the context of variants at [0055] of the PG Pub. The arguments state similarity is determined by using BLAST and refers to protein homologues.
In response: The arguments are not persuasive. The Specification does not provide a definition for the term similarity. Section [0055] defines a “variant”. It does not define the term “similar”. Examiner notes page 10 of the arguments allege claim 1 recites “variants with at least 80% sequence similarity/identity”. None of the claims recite variants with at least 80% identity. If the Applicant is attempting to claim variants with at least 80% identity, the claims should be amended.
Claim Rejections - 35 USC § 102
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1, 5-6 and 22-23 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Rijn et al. (previously cited; Pickering Emulsion templated soft capsules by self-assembling cross-linkable ferritin-polymer conjugates. Chem. Commun., 2011, 47, 8376-8378).
Rijn et al. disclose oil-in-water (o/w) and water-in-oil (w/o) Pickering emulsions prepared using ferritin–polymer conjugates” (Abstract). Rijn teaches the following (page 8376, right column, second paragraph):
Here we report on a bionanoparticle–polymer hybrid material recently developed by our group. It consists of a ferritin protein cage which is decorated on the outside with PNIPAAm/DMIAAm co-polymers (poly(N-isopropyl acrylamide)/2-(dimethyl maleinimido)-N-ethyl-acrylamide) via ATRP (atom transfer radical polymerisation). Due to their high affinity towards polar–apolar interfaces, the ferritin– PNIPAAm conjugates were found to stabilise emulsions very efficiently even at low concentrations. These Pickering emulsions, in which the stabilisers are particles instead of surfactants, are stabilised further via cross-linking the self assembled protein–polymer shell (S1, ESIw). Therefore, in addition to the well-known PNIPAAm, a photo-responsive cross-linker moiety24 (DMIAAm) was copolymerised.
Rijn teaches the following (page 8376, left column, last paragraph):
These days, emulsion stabilisation and capsule formation using nanoparticles, so called Pickering emulsions, is seen as a highly promising approach. These particles owe their stabilising effect to high attachment energies at liquid–liquid interfaces and range from inorganic particles to proteins and polymer nanoparticles and led to interesting architectures like colloidosomes and yeastosomes. The use of particles as stabiliser results in oil-in-water (o/w) as well as water-in-oil (w/o) emulsions depending on the polarity of the particle and therefore both a polar and an apolar liquid core can be obtained.
As set forth above, Rijn teaches a Pickering emulsion comprising a bionanoparticle-polymer hybrid (hence, a nanoparticle) protein cage (ferritin). The art teaches the protein cage has “high affinity towards polar–apolar interfaces” (supra). An amphiphile is a compound with hydrophilic (polar) and hydrophobic (nonpolar) regions. Therefore the protein cage taught by has amphiphilic properties. The emulsion comprises the phases recited in claim 1 and has liquid-liquid interface. “As determined by BLAST algorithm” is a product by process limitation that does not distinguish the claimed variant from the ferritin protein cage taught by Rijn. The protein cage is interpreted to read on a protein variant with at least 80% similarity to the ferritin proteins recited in claim 1. See MPEP 2113 II. Therefore claim 1 is anticipated.
Rijn teaches the use of water in a water and oil emulsion (supra). Therefore claim 5 is included in this rejection .
Rijn teaches oil (hence, a water-immiscible liquid) to prepare emulsions (supra). Therefore claim 6 is included in this rejection.
The ferritin taught by Rijn is broadly interpreted to read on the ferritin variants recited in claim 22.
The ferritin taught by the art is broadly interpreted to read on the ferritin variants recited in claim 23.
Therefore Applicant’s Invention is anticipated as claimed.
RESPONSE TO APPLICANT’S ARGUMENTS
The arguments made in the response filed on 16 September 2025 are acknowledged. The arguments state claim 1 is limited to AtFtn SEQ ID 3 (A. fulgifus) and AtfFtn-AA SEQ ID 4 (human). The Applicant argues Rijn does not teach the claimed species. The Applicant argues Rijn teaches horse ferritin.
In response: The variant recited in claim 1 is not limited to a protein from human or A. fulgifus. claim 1 recites a variant with at least 80% sequence similarity. As set forth above, the metes and bounds of “similarity” is unclear. Therefore the ferritin taught by Rijn reads on the claim. Rijn teaches a pickering emulsion comprising a protein cage. Rijn teaches the protein cage has “high affinity towards polar–apolar interfaces” (supra). An amphiphile is a compound with hydrophilic (polar) and hydrophobic (nonpolar) regions. Examiner notes on page 12 of the arguments, the Applicant acknowledges the protein cage taught by Rijn has “native amphiphilic character” (see eighth line from the bottom). Therefore the protein cage taught by Rijn has amphiphilic properties. The arguments are not persuasive.
Claim Rejections - 35 USC § 103
Claim 21 is rejected under 35 U.S.C. 103 as being unpatentable over Rijn et al. in view of Chen et al. (previously cited; Preparation of Novel W/O Gel-Emulsions and Their Application in the Preparation of Low-Density Materials. Langmuir 2012, 28, 9275−9281).
Claim 1 is rejected on the grounds set forth above. The teachings of Rijn et al. are reiterated. As set forth above, Rijn et al. disclose capsules containing Pickering emulsion comprising a ferritin protein cage which is decorated on the outside with PNIPAAm/DMIAAm co-polymers (poly(N-isopropyl acrylamide)/2-(dimethyl maleinimido)-N-ethyl-acrylamide). Examiner notes Rijn teaches PNIPAAm is often used in micro-gel structures meaning that it is able to hold a significant amount of water.
Rijn teaches self-assembly of molecular components and nanoparticles has been used to stabilise emulsions, form membranes and prepare capsules. Especially the latter is of great interest as these structures are used by many different industrial branches in a large variety of consumer goods, e.g. drug delivery, perfumes, foods or inks. See page 8376, left column, first paragraph.
While Rijn discloses a Pickering emulsion comprising a polymer often used in microgels, the art does not explicitly teach the emulsion is a gel.
Chen teaches gel-emulsions are two-phase systems, of which one is the internal or dispersed phase, and another is the continuous phase. Unlike routine emulsions, gel-emulsions possess typical rheological properties of physical gels. Practically, gel-emulsions have been widely used in food, cosmetics, medicine, chemical industry, and as templates for the preparation of various materials with porous structures and so on. Because of the fascinating properties and the widespread uses, creation of new gel-emulsions and extension of their applications have become a hot point of soft matter research (see page 9275, left column, first paragraph). Gel-emulsions can be classified into two categories: oil-in-water (O/W) and water-in-oil (W/O). Stabilizers used for the stabilization of the gel-emulsions could be surfactants, micro-/nanoparticles, and possibly low-molecular mass gelators (LMMGs) (see page 9275, left column, second paragraph).
It would have been obvious to combine the teachings of the prior art by preparing an emulsion that is a gel. Rijn teaches a o/w and w/o Pickering emulsion stabilized with a nanoparticle and Chen teaches emulsions stabilized with nanoparticles can be used to prepare gel-emulsions. One would have been motivated to do so since Rijn teaches capsules can be used for drug delivery (hence, for medical purposes) and Chen teaches gel-emulsions are widely used in medicine. One would have had a reasonable expectation of success since Chen teaches gel-emulsions can be stabilized with nanoparticles, and Rijn teaches the use of a nanoparticle to stabilize an emulsion. One would have had a reasonable expectation of success since Rijn and Chen are directed to stabilized emulsions. Therefore claim 21 is rendered obvious as claimed.
Therefore Applicant’s Invention is rendered obvious as claimed.
Claims 1 and 5-6 are rejected under 35 U.S.C. 103 as being unpatentable over Campion et al. (previously cited; Targeted Protein Cages. US20090035389) in view of Fujii et al. (previously cited; Ferritin as a bionano-particulate emulsifier. Journal of Colloid and Interface Science 338 (2009) 222–228) as evidenced by Ameen et al. (The clinical applications of ferritin. World Journal of Biology Pharmacy and Health Sciences 2022 12(01, 137-147).
Campion teaches protein cages (hence, a nanoparticle) for the specific delivery of a variety of agents to cells and tissues (Abstract). The protein cages have targeting moieties and therapeutics which are encapsulated within the protein cages or are located on the exterior surface of the cages (Abstract ;[0004]). The protein cages can be ferritin or heat shock proteins (see Figure 1A; [0013] [0027]-[0030]). As evidenced by the Instant Specification, a heat shock protein is a protein cage ([0048]). As evidenced by the specification, an “intrinsic” property of protein cages is their “amphiphilic properties” ([0047] of PG Pub). As evidenced by Ameen et al., ferritin comprises hydrophilic and hydrophobic channels (see last two lines of page 137, bridging second paragraph of page 138). Therefore heat shock protein and ferritin are protein cages with amphiphilic properties.
Campion teaches the protein cages can be formulated in emulsions ([0095]).
While the art teaches formulation as an emulsion, the art is silent regarding a Pickering emulsion. While the art teaches heat shock proteins, the art does not do so with sufficient specificity to anticipate claim 1.
Fujii teaches bionanoparticles can be used to stabilize emulsions (see second paragraph of Introduction). The art teaches bionanoparticles, such as viruses, protein and other biological materials, are monodisperse in size and can be functionalized in a robust, well-defined manner (same cited section). The art teaches a bionanoparticle that is a protein cage (ferrtin) can be used as an emulsifier to make a stable Pickering emulsion (Abstract), third and fourth paragraph of Introduction). The art teaches an oil-in-water type emulsion (Abstract). The art teaches the bionanoparticle is at the oil-water interface (see first paragraph of Conclusions).
It would have been obvious to try using the protein cages taught by Campion to make a Pickering emulsion. One would have been motivated to do so since Campion teaches formulating a protein cage in an emulsion and Fujii teaches protein cages can be used to make a Pickering emulsion. One would do so to produce a stabilized emulsion. The skilled artisan would include an oil and water phase since Fujii teaches these are phases in a Pickering emulsion. One would have had a reasonable expectation of success since Fujii teaches a protein cage can be used to make a Pickering emulsion with the claimed properties. One would have expected similar results since both references are directed to protein cages prepared as emulsions.
It would have been obvious to try using heat shock proteins since Campion identifies these as protein cages that can be used. KSR Rationale E indicates that “a person of ordinary skill has good reason to pursue the known options within his or her technical grasp. If this leads to the anticipated success, it is likely the product not of innovation but of ordinary skill and commonsense” (MPEP 2143 “Rationale E. Obvious to Try” section). Therefore claim 1 is rendered obvious.
Fujii uses water for an aqueous phase (an oil-in-water emulsion). Therefore claim 5 is included in this rejection. Fujii uses oil (hence, a water-immiscible liquid) to prepare emulsions (supra). Therefore claim 6 is included in this rejection.
Therefore Applicant’s invention is rendered obvious as claimed.
RESPONSE TO APPLICANT’S ARGUMENTS
The arguments made in the response filed on 16 September 2025 are acknowledged.
The arguments allege the claims recite “variants with at least 80% sequence similarity/identity”. The Applicant argues horse ferritin in excluded. The Applicant argues that in light of Rijn or Fuji, one would be directed toward using mammalian ferritins. The Applicant argues the protein cages have amphiphilic properties not recognized by the prior art. The Applicant argues “Campion fails to disclose , teach or suggest the use of ferritin that is derived from Bacillus stearathermophilus (E2, E2LC2) or A. fulgidus (AdDt, AfFtn-AA). The Applicant argues the reference does not teach the protein cage has amphiphilic properties. The Applicant argues Campion does not teach a pickering emulsion. The Applicant argues impermissible hindsight reasoning.
In response: Contrary to the arguments, none of the claims recite variants with at least 80% identity. The claims recite variants with at least 80% similarity. The claim language has been rejected under 35 USC 112b.
The Applicant argues Campion does not teach “ferritin that is derived from Bacillus stearathermophilus (E2, E2LC2)”. Examiner notes the claims and specification identify E2 as “pyruvate dehydrogenase multi-enzyme complex”. It is not ferritin. E2CL2 is a modified version of E2. Therefore the arguments made by the Applicant appear to misidentify the claimed proteins.
While the Applicant argues Campion would lead one of ordinary skill to only use mammalian proteins, Campion teaches heat shock proteins can be from bacteria (see ([0030]). Campion teaches heat shock protein. Claim 1 recites heat shock protein. The claims are not limited to a species of heat shock protein. Campion teaches ferritin protein cages can be derived from eukaryotic and prokaryotic species, in particular mammalian and bacterial ([0028]). As evidenced by the specification, amphiphilic properties are intrinsic to protein cages. Examiner notes on page 12 of the arguments, the Applicant acknowledges the protein cage taught by Rijn (ferritin) has “native amphiphilic character” (see eighth line from the bottom).
While Campion teaches the protein cage can be formulated in an emulsion, the art does not explicitly teach a “picking” emulsion. It would have been obvious to try using the protein cages taught by Campion to make a Pickering emulsion. One would have been motivated to do so since Campion teaches formulating a protein cage in an emulsion and Fujii teaches protein cages can be used to make a Pickering emulsion. One would do so to produce a stabilized emulsion. The skilled artisan would include an oil and water phase since Fujii teaches these are phases in a Pickering emulsion. One would have had a reasonable expectation of success since Fujii teaches a protein cage can be used to make a Pickering emulsion with the claimed properties. One would have expected similar results since both references are directed to protein cages prepared as emulsions.
Protein cages are taught by the prior art. As evidenced by the specification, amphiphilic properties are inherent to protein cages. Pickering emulsions comprising protein cages comprising heat shock proteins and ferritin are taught by the prior art. The rejection is based on knowledge which was within the level of ordinary skill in the art at the time the claimed invention was made. See MPEP 2145. Therefore the arguments are not persuasive.
Claim 7 is rejected under 35 U.S.C. 103 as being unpatentable over Campion in view of Fujii as applied to claim 1 above, and further in view of Cosmetic Ingredient Review et al. (previously cited; Safety Assessment of Rosmarinus Officinalis (Rosemary)-Derived Ingredients as Used in Cosmetics. 2013, pages 1-91) and Peng et al. (previously cited; Trimer-Based Design of pH-Responsive Protein Cage Results in Soluble Disassembled Structures. Biomacromolecules 2011, 12, 3131–3138).
Claim 1 is rejected on the grounds set forth above. The teachings of the prior art are reiterated. Campion teaches protein cages. The cages can be formulated as an emulsion. The protein cage can be viral or non-viral ([0013]). Campion teaches In some embodiments, the protein cage is modulated by a chemical switch ([0018]). Examples of such chemical switches include those modulated by pH, redox potential, and ionic strength. Such chemical switches can be reversible or irreversible ([0018]).
Campion is silent regarding preparation as a Pickering emulsion.
The art is silent regarding the use of an E2 protein cage.
Fujii teaches the use of five oils, including castor oil, olive oil or vegetable oil as the oil phase in a Pickering emulsion (Abstract). Fujii teaches the following (page 223, right column, last paragraph):
In order to check the ability of the ferritin nanoparticles as a Pickering-type emulsifier, five oils, namely n-dodecane, toluene, castor oil, olive oil and vegetable oil, were used as an oil phase to prepare emulsions at a ferritin concentration of 1.00 wt.% (see Table 1 and Fig. S3). n-Dodecane and toluene were used in order to characterize emulsions in detail and the other three oils were used as biocompatible model oils which can be used for biomedical applications. In all the cases, highly stable oil-in-water emulsions were achieved and optical microscopy studies revealed that emulsion droplets stably dispersed in aqueous continuous phase without coalescence. All the emulsions prepared in this study survived at least 10 months and nearly 100% emulsions were remained in closed system where the evaporation of oil and water are not allowed.
While the art teaches explicitly teaches the use of a protein cage, and discloses a variety of nanoparticles have been used to stabilize emulsions, neither reference teaches an E2 protein.
While Fujii teaches the use of oils that are biocompatible, the art is silent as to whether rosemary oil can be used.
The Cosmetic Ingredient Review teaches Rosmarinus officinalis L. is GRAS as a spice and other natural seasoning and flavoring when the intended use is for human consumption (21CFR182.10) and for animal drugs, feed, and related products (21CFR582.10). It is also GRAS as an essential oil, oleoresin (solvent-free), and natural extractive (including distillates) for human consumption (21CFR182.20) and for animal drugs, feed, and related products (21CFR582.20)… Rosemary is reported to have use as an anti-inflammatory, antioxidant, and anti-microbial agent…. As the oil or as an ointment, external application use is as an analgesic liniment for rheumatism. Rosemary is used as a poultice for poorly healing wounds and in the treatment of eczema. It is used in lotions to treat baldness,18 and the leaves and branches have been used for treating headaches. (see Non-Cosmetic” section at bottom of page 3). Because rosemary oil is generally regarded as safe, it is broadly interpreted to be biocompatible. Because the art teaches it is known for use to treat medical conditions, it is interpreted to be suitable for biomedical applications.
Peng et al. teach the following (page 3131, first paragraph bridging first paragraph of right column):
Protein cages, such as those in ferritin family, virus, and virus like particles, are formed by the self-assembly of a distinct number of protein subunits into multimeric, hollow, and nanoscale structures. These protein cages have been drawing much attention across multiple scientific research fields. For example, they are widely studied as nanoscale carriers in drug delivery and as platforms for the synthesis of nanostructured materials that can potentially be used as catalysts or to facilitate medical imaging.
Peng investigates a virus-like protein cage, E2 core domain (dihydrolipoamide acetyltransferase) of pyruvate dehydrogenase (PDH) complex from Bacillus stearothermophilus. The E2 protein has 60 identical subunits that self-assemble into a hollow, spherical protein cage with icosahedral symmetry (page 3131, left column, last paragraph). Unlike viral proteins, the virus-like E2 protein lacks infectious capacity, which makes it an attractive molecule for potential application as nanocapsule in drug delivery. A recently generated E2 scaffold consisting of only the core, caged structure with correct assembly and high thermostability has been designed to encapsulate druglike small molecules. Functionalities of the E2 protein are expandable by introducing modifications at the exterior, interior, or subunit interfaces. The exterior surface of E2 can be modified with antigenic peptide to facilitate vaccine development. Introduction of cysteine residues at the interior surface allow E2 protein to encapsulate fluorescent dye while its hollow caged structure remained unchanged (page 3131, left column, last paragraph bridging first paragraph of right column).
Peng investigates E2-WT (wild type E2) in addition to mutants E2-(2 + 2)H and E2-4H (first paragraph of Results and Discussion). The art teaches each form a protein cage (see last paragraph of 3133 through first paragraph of 3134). The wildtype taught by the prior art appears to be the same as the E2-WT disclosed in the Instant Specification.
It is also of note the art also teaches the following (page 3132, left column, second paragraph):
Other protein cages, such as human ferritin light chain, could be modified at their subunit interface by incorporating a GALA peptide that resulted in a pH-responsive ferritin protein cage. In this investigation, we focus on modifying the interactions between subunits to design a novel pH-sensitive E2 protein cage
Examiner notes the following from the Instant Specification:
The E2 protein is part of the multienzyme pyruvate dehydrogenase complex. The pyruvate dehydrogenase complex comprises three subunits, E1, E2, and E3. In this complex, the E2 subunits form the core upon which E1 and E3 are bound. Sixty E2 subunits self-assemble into a dodecahedron cage. Its crystallographic structure shows that the assembled structure has a hollow core of approximately 25 nm in diameter with 12 openings of 5 nm each. By replacing two amino acids on wild-type E2 (E2-WT) (SEQ ID NO:1, PDB ID: 1B5S, amino acid #381-382), namely aspartic acid and glycine, by cysteine, the inventors of the present invention have created protein cage E2LC2 (SEQ ID NO:1) with reactive —SH groups, which can be reactive with bifunctional agents, such as maleimide to attach agents to the protein cage
The Instant Specification identifies wild-type E2 (E2-WT) as SEQ ID NO:1.
It would have been obvious to use rosemary oil as the oil phase in a Pickering emulsion. One would have been motivated to do so since Fujii discloses the use of plant based, bio-compatible oils suitable for use in biomedical applications to produce an oil phase and rosemary oil is a plant based, biocompatible oil that can be used in biomedical applications. KSR B teaches that it is rational to substitute one known, equivalent element for another to obtain predictable results. One would have expected similar results since the Fujii teaches the use of a plant based, bio-compatible oils and rosemary oil is a plant based, bio-compatible oils.
It would have been obvious to try using the wild type E2 protein cage taught by Peng as a protein cage. One would have been motivated to do so since Campion teaches the use of viral protein cages and Peng teaches E2 is a viral protein cage. One would have had a reasonable expectation of success since Campion teaches the protein cage can be modulated by a pH switch and Peng’s cage is pH sensitive. Peng teaches the virus-like E2 protein lacks infectious capacity. One would have been motivated to use wild type E2 since Campion teaches a protein cage for drug delivery and Peng teaches this feature makes it an attractive molecule for potential application as nanocapsule in drug delivery. Peng investigates E2-WT (wild type E2). The Instant Specification identifies wild-type E2 (E2-WT) as SEQ ID NO:1. Therefore the E2 taught by Peng is interpreted to read on the claim. Any differences are interpreted to be obvious. One would have had a reasonable expectation of success using it in a Pickering emulsion since Fuji teaches virus bionanoparticles can be used as nano-scale particulate emulsifiers to stabilize emulsions. Therefore claim 7 is rendered obvious.
Therefore Application’s Invention is rendered obvious as claimed.
Claims 1, 5-6 and 22-23 are rejected under 35 U.S.C. 103 as being unpatentable over Rijn et al. in view of Sana (previously cited).
The teachings of Rijn as set forth above are reiterated.
While Rijn teaches ferritin, the art is silent regarding the claimed ferritin sequence variants.
Sana teaches Archaeoglobus fulgidus ferritin (AfFtn) is the only tetracosameric ferritin known to form a tetrahedral cage, a structure that remains unique in structural biology (page 32663, let column, first paragraph). The art teaches AfFtn and AfFtn-AA are able to bind and release iron (Abstract; Figure 8A and 8B). As evidenced by the Instant Specification SEQ ID No: 3 is AfFtn and SEQ ID No: 4 is AfFtn-AA ([0011]). Examiner notes Sana compares the binding kinetics of AfFtn and AfFtn-AA was with that of PfFtn (Figure 8A). PfFtn has a closed octahedral shell that is characteristic of ferritins (page 32664, left column, second paragraph). AfFtn and AfFtn-AA (tetrahedral cage) and PfFtn (octahedral cage) are able to bind and release iron (Figure 8A an 8B).
It would have been obvious to substitute AfFtn or AfFtn-AA in the Pickering emulsion taught by Rijn. One would have been motivated to do so since Rijn teaches a Pickering emulsion comprising a ferritin cage, and Sana teaches AfFtn and AfFtn-AA are ferritin cages. KSR B teaches it is rational to substitute one known, equivalent element for another to obtain predictable results. In the Instant case, the ferritins disclosed by Fujii and Sana form a cage. Each ferritin is able to transport iron. One would have had a reasonable expectation of success using AfFtn or AfFtn-AA since they have the same properties as the ferritin used by Sana. One would have expected similar results since each reference is directed to a ferritin cage protein.
Sana teaches AfFtn and AfFtn-AA are able to bind and release iron. As evidenced by the Instant Specification SEQ ID No: 3 is AfFtn and SEQ ID No: 4 is AfFtn-AA.
Therefore the protein cages taught by Sana are interpreted to read on the claimed variants. Any differences are interpreted to be obvious.
Therefore claim 1 is rendered obvious.
The art teaches the use of water in a water and oil emulsion (supra). Therefore claim 5 is included in this rejection. The art teaches the use of oil (hence, a water-immiscible liquid) to prepare emulsions (supra). Therefore claim 6 is included in this rejection.
Claims 22-23 are rendered obvious on the grounds set forth in the rejection of claim 1.
Therefore Applicant’s Invention is rendered obvious as claimed.
RESPONSE TO APPLICANT’S ARGUMENTS
The arguments made in the response filed on 16 September 2025 are acknowledged.
Regarding Sana et al.: The Applicant argues Sana merely characterizes the structural features of AfFtn and AfFtn-AA in the contact of iron storage. The Applicant argues Sana does not teach an emulsion or amphiphilic properties.
.
In response: Sana is not relied upon to teach an emulsion. Rijn teaches a pickering emulsion comprising ferritin, a naturally occurring protein cage. Rijn teaches
the protein cage has “high affinity towards polar–apolar interfaces” (supra). An amphiphile is a compound with hydrophilic (polar) and hydrophobic (nonpolar) regions. Therefore the protein cage taught by Rijn has amphiphilic properties. Sana is relied upon because it teaches the claimed ferritin sequences recited in claim 1.
It would have been obvious to substitute AfFtn or AfFtn-AA in the Pickering emulsion taught by Rijn. One would have been motivated to do so since Rijn teaches a Pickering emulsion comprising a ferritin cage, and Sana teaches AfFtn and AfFtn-AA are ferritin cages. KSR B teaches it is rational to substitute one known, equivalent element for another to obtain predictable results. In the Instant case, the ferritins disclosed by Fujii and Sana form a cage. Each ferritin is able to transport iron. One would have had a reasonable expectation of success using AfFtn or AfFtn-AA since they have the same properties as the ferritin used by Sana. One would have expected similar results since each reference is directed to a ferritin cage protein.
Claim 21 is rejected under 35 U.S.C. 103 as being unpatentable over Rijn in view of Sana as applied to claim 1 above, and further in view of Chen et al.
Claim 1 is rejected on the grounds set forth above. The teachings of Rijn et al. are reiterated.
As set forth above, Rijn et al. disclose capsules containing Pickering emulsion comprising a ferritin protein cage which is decorated on the outside with PNIPAAm/DMIAAm co-polymers (poly(N-isopropyl acrylamide)/2-(dimethyl maleinimido)-N-ethyl-acrylamide). Examiner notes Rijn teaches PNIPAAm is often used in micro-gel structures meaning that it is able to hold a significant amount of water.
Rijn teaches self-assembly of molecular components and nanoparticles has been used to stabilize emulsions, form membranes and prepare capsules. Especially the latter is of great interest as these structures are used by many different industrial branches in a large variety of consumer goods, e.g. drug delivery, perfumes, foods or inks.
While Rijn discloses a Pickering emulsion comprising a polymer that is often used in microgels, the art does not explicitly teach the emulsion is a gel.
Chen teaches gel-emulsions are two-phase systems, of which one is the internal or dispersed phase, and another is the continuous phase. Unlike routine emulsions, gel-emulsions possess typical rheological properties of physical gels. Practically, gel-emulsions have been widely used in food, cosmetics, medicine, chemical industry, and as templates for the preparation of various materials with porous structures and so on. Because of the fascinating properties and the widespread uses, creation of new gel-emulsions and extension of their applications have become a hot point of soft matter research (see page 9275, left column, first paragraph). Gel-emulsions can be classified into two categories: oil-in-water (O/W) and water-in-oil (W/O). Stabilizers used for the stabilization of the gel-emulsions could be surfactants, micro-/nanoparticles, and possibly low-molecular mass gelators (LMMGs) (see page 9275, left column, second paragraph).
It would have been obvious to combine the teachings of the prior art by preparing an emulsion that is a gel. One would have been motivated to do so since Rijn teaches a o/w and w/o Pickering emulsion stabilized with a nanoparticle and Chen teaches emulsions stabilized with nanoparticles can be used to prepare gel-emulsions. One would have been motivated to do so since Rijn teaches capsules can be used for drug delivery (hence, for medical purposes) and Chen teaches gel-emulsions are widely used in medicine. One would have had a reasonable expectation of success since Chen teaches gel-emulsions can be stabilized with nanoparticles, and Rijn teaches the use of a nanoparticle to stabilize an emulsion. One would have had a reasonable expectation of success since Rijn and Chen are directed to stabilized emulsions. Therefore claim 21 is rendered obvious as claimed.
Therefore Applicant’s Invention is rendered obvious as claimed.
CONCLUSION
No Claims Are Allowed
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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 extension fee 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 date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to NATALIE MOSS whose telephone number is (571) 270-7439. The examiner can normally be reached on Monday-Friday, 8am-5pm EST.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Sharmila Landau can be reached on (571) 272-0614. The fax phone number for the organization where this application or proceeding is assigned is (571) 273-8300.
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/NATALIE M MOSS/ Examiner, Art Unit 1653
/SHARMILA G LANDAU/ Supervisory Patent Examiner, Art Unit 1653