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
Claim Status
Claims 1,6,11,12,13, and 17 are amended.
Claims 2, 7, 14 are cancelled.
Claims 1, 3-6, 8-13, and 15-17 are under examination.
Withdrawn Objections
The objection raised against the specification for containing an embedded hyperlink is withdrawn in light of Applicants amendments deleting the hyperlinks.
Withdrawn Rejections
Rejections under 35 USC § 102
The rejection of Claims 1-2, 4-7, 9-14 and 16-17 under 35 U.S.C. §102 (a)(l) as being
anticipated by He et al, as evidenced by Hayman et al is withdrawn in light of claims amendment. Applicants has amended the claim to delete the alternative recitation of
" or the coat layer includes the layer (i), the layer (i) is disposed at a position at which the
layer (i) comes into contact with the cells, and the culture medium includes the cell adhesion factor", and adding a new limitation that recite" wherein the cell adhesion factor comprises one or more of laminin, collagen, fibronectin and fibrinogen". In view of this amendment, the rejection is no longer applicable to the claims as presently amended.
Rejections under 35 USC § 103
The rejection of Claims 3, 8 and 15 under 35 U.S. C. § 103 as being unpatentable over
He et al. in view of Sghayyar et al. is withdrawn in light of claims amendments. The rejection is no longer applicable to the claim as presently amended.
Claim Interpretation
As per the specification, the term “easily peelable cells”, recited in instant claims 5 and 10, includes cells that are peeled from the culture surface of a cell culture container simply by the application of shocks or vibration to the cell culture container. Specific examples of easily peelable cells include cell aggregates including nerve cells, HEK293, which is a human embryonic kidney cell line, and the like. ( See [0045] on page 15-16)
Edited Rejections Necessitated by Claims Amendments
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.
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1,4-6,9-13, and 16-17 are rejected under 35 U.S.C. 103 as being unpatentable over He et al ( Biomaterials, 2005), in view of Seiten et al (Journal of Neuroscience, 2020), and Flanagan et al ( Journal of Neuroscience, 2006).
Regarding claims 1, 6, and 17, He et al utilize the electrostatic layer-by-layer (LbL) method to coat silicon wafers with multilayers comprising of polycation and proteins. The method involves building alternating layers of polycation (i.e. polyethyleneimine (PEI) or chitosan) and protein (i.e. gelatin or laminin) to fabricate multilayer films on silicon wafers. For example, one of the coatings taught by He et al comprises of 8 bilayers of PEI and gelatin (i.e. PEI-gelatin)8, with each bilayer comprising a layer of PEI followed by a layer of gelatin. ( See 2.1.2 on page 2984). It should be noted that the gelatin layer reads on (i-1), the polycation layer reads on (i-2), and the bilayer comprising PEI-gelatin reads on layer (i). He et al also teach utilizing the coated wafers to test their ability to promote neuronal attachment and differentiation. For example, He et al teach culturing chick cortical neurons, which is a type of adherent cells, at a density of 75,000 cells/cm2 in 24-well plates that contained silicon wafers coated with LbL coatings. ( See 2.3.2 and 2.3.3.). Thus, He et al teach the use of polycationic material in combination with gelatin to form a multilayer cell-interactive coat on a substrate. He et al further demonstrate the utility of these coatings for adhesion and differentiation of cortical neurons. In addition, He et al teach another coating comprising of PEI-gelatin bilayer and further chitosan-gelatin bilayers deposited thereon (i.e. PEI-gelatin-CH-gelatin)7; wherein the gelatin of said first bilayer can be seen as the layer (i-1 ), and the PEI as the polycationic material of layer (i-2) in claim 1 terminology; and gelatin of the further bilayers on said first PEI-gelatin can be seen as a "cell adhesion factor" within the scope of the instant claim, because gelatin is derived from collagen which is a major component of the ECM. ( See Figs.4-5).. Furthermore, the coating comprising of ( PEI-gelatin-CH-gelatin)7 is ended with gelatin (i.e. gelatin is the outermost layer). In other words, gelatin is being in contact with cells. Gelatin is a well-known cell adhesion factor, therefore, the outermost layer comprising gelatin reads on the layer (ii) of the instant claims. Taken together, under the broadest reasonable interpretation of instant claim, the coating comprised of ( PEI-gelatin-CH-gelatin)7 , as taught by He et al, reads on the (i) and (ii) layers. As such, the PEI layer reads on the (i-2) layer, the subsequent gelatin layer reads on the (i-1) layer, and the outermost layer of gelatin reads on (ii) layer. However, He et al do not teach the specific combination of gelatin, a polycationic layer, and a layer comprising an adhesion factor, wherein the adhesion factor is selected from laminin, collagen, fibronectin or fibrinogen.
Setien et al supplement He et al by evaluating four commonly used substrate for rat iPSCs-derived neural progenitor cells, including poly-L-ornithine in combination with laminin, and gelatin. Setien et al report that the combination of poly-Ornithine (i.e. polycationic) with laminin coating promoted neuronal arborization and maturation, whereas gelatin was the least favorable substrate for growth and differentiation of the tested cells. Setien et al further reports that gelatin was an inefficient coating strategy for producing neurons under the tested conditions. ( See abstract, and Fig.2). Setien et al further explains the respective functions of the components. For example, Setien et al state that “Laminin promotes adherence through its binding domains, which have been shown to increase cell expansion, differentiation, and neurite outgrowth of NPCs derived neurons in combination with polyornithine. Setien et al further state that although gelatin may be an adequate substrate for neuronal differentiation in certain contexts (e.g., differentiation of murine embryonic stem cells via induction of proneural factors), it has also been reported that gelatin is not an ideal substrate candidate for promoting NPCs neurite outgrowth or homogeneous differentiation”. ( See section 4.1. on page 7). In other words, Setien et al teach that while gelatin may be suitable in certain cellular context, however, laminin become the ideal substrate for promoting NPCs neurite outgrowth or homogeneous differentiation. Setien et al also teach that laminin provides a binding domain for cells which facilitate cell adhesion and is used in cell differentiation. As such, Setien et al identify a known limitation of gelatin as a neuronal culture substrate and identifies the combination of poly-L-ornithine/Laminin as a more favorable substrate for neuronal differentiation. Accordingly, Setien et al teach that the combination of polycationic layer topped with cell adhesion molecules, such as laminin are known, and that a polycationic material followed by laminin provides a known neuronal culture surface having a favorable neuronal characteristic. Setien et al’s teachings also provide an ordinary skill in the art with the knowledge that a coating comprising both gelatin and laminin may provide a substrate having broader applicability for supporting adhesion, differentiation, and growth of multiple cell types.
Flanagan et al further supplement Setien et al by teaching that laminin is an extracellular matrix cell-adhesion molecule having specific biological interaction with neural precursor cells. Specifically, Flanagan et al compare poly-L-ornithine (i.e. polycationic), Fibronectin, laminin, and Matrigel as substrates for human neural precursor cells. Flanagan et al show that laminin enhanced neural precursor-cell migration, expansion, neuronal and astrocytic differentiation, and neurite elongation. Flanagan et al further identifies laminin binding integrins α3, α6, α7, β1, and β4 on the surface of human NPCs and demonstrate a role for integrins in laminin-dependent cellular behavior. ( See abstract). Thus, the combined teachings of Setien and Flanagan demonstrate that laminin was known to provide specific cell-substrate adhesion interface in the context of neural precursor cells.
Taken together, it would have been prima facie obvious to one with ordinary skill in the art at the time the invention was filed to modify the multilayer coating technology of He et al by replacing gelatin with laminin as the cell-facing adhesion factor, while retaining a polycationic material as an intermediate layer. Because He et al teach a multilayer coatings technology in which polycationic materials are combined with proteinaceous materials including gelatin and laminin, and specifically disclose a coating comprising of multiple layers, with gelatin as the first layer, a polycationic layer as an intermediate layer, and gelatin as the outermost layer. The combined teachings of Setien and Flanagan further demonstrate that laminin was known to provide specific cell-substrate adhesion interface for neural precursor cells and expressly demonstrate its suitability as an outermost coating layer for promoting NPCs neurite outgrowth and homogeneous differentiation. Thus, an ordinary skill in the art who had reviewed He et al, could have come across Setien and Flanagan and immediately would have recognized the limitations of gelatin for supporting the growth and differentiation of neuronal cells, and would have understood that laminin could be substituted at the cell interface to achieve the desired cellular response. An ordinary skill in the art would have had a reasonable expectation that the combination would have been a predictable use of known materials to their known functions. In other words, instant claims are combining prior art elements according to known methods to yield predictable results. See MPEP 2143 (I)(A).
Regarding claim 4 ,9, and 16, He et al teach the use of polyethyleneimine.
Regarding claim 5 and 10 , He et al teach using the coated silicon wafers to culture chick cortical neurons, which are considered to be easily peelable cells. See claim interpretation above.
Regarding claims 11, following the discussion of claim 1 above, the method of He et al for coating the silicon wafers include the following step:
Brining a solution containing PEI into contact with silicon wafers for 30 mins to initiate the LbL self-assembly.
Removing the excess by rinsing the surface with deionized water for 1 mins.
Coating the silicon wafers with a solution containing gelatin, then rinsing with deionized water for 1 mins . ( See 2.1.1-2.1.2 on page 2984).
As previously discussed, the method of He et al further involves coating the bilayer containing PEI-gelatin with 7 bilayers containg chitosan-gelatin i.e. (ii) layer, with the gelatin being the outermost layer and hence comprising a cell adhesion factor in contact with the cells. It should be noted that the coating with chitosan-gelatin also involves exposing the wafer to a solution containing either chitosan or gelatin followed by removing the excess by washing with deionized water before the subsequent addition of the alternating layer. Taken together, the method of He et al involves the production of layers starting with (i) layer comprising (PEI-gelatin), then the (ii) layer comprising chitosan-gelatin, this reads on the order of (3), the (4), the (1), the (2), the (5), and the (6) of instant claim, and as discussed in claim 1 above, He in view of Setien and Flanagan render obvious the coating of laminin as being the outermost layer instead of gelatin in the coatings taught by He et al. Accordingly, the combined teachings of He, Setien, and Flanagan render obvious instant claim.
Regarding claims 12-13, the method of He et al also involves carrying out a hydrophilic treatment on the surface of the cell culture container before coating with PEI or gelatin. The hydrophilic treatment includes applying an ethanol solution
to the surface of the cell culture container and then removing it with deionized water. ( See 2.1.2. on page 2984).
Claims 3,8, and 15 are rejected under 35 U.S.C. 103 as being unpatentable over He et al, in view of Setien and Flanagan as applied to claims1,4-6,9-13, and 16-17 above and further in view of Sghayyar et al ( European Polymer Journal, 2020).
The teachings of He et al , Setien and Flanagan eta al are set forth above.
Regarding claims 3,8, and 15, following the discussion above, He et al teach gelatin that is derived from porcine skin.(See 2.1.1 on page 2984). It is submitted that none of the cited prior arts teach gelatin derived from fish.
Sghayyar et al teach utilizing gelatin derived from fish to coat phosphate-based glass fibers (PGFs) in order to investigate its potential use in wound healing application. Specifically, Sghayyar et al demonstrate that culturing adult human skin keratinocytes (HaCaT) on PGFs coated with gelatin derived from fish promoted HaCaT cell adhesion, migration and proliferation. According to Sghayyar et al, gelatin derived from fish perform very well as a coating for PGFs, improving cytocompatibility and cell interaction on their surface. Sghayyar et al also state that “Fish gelatin has been recognized as a safer, economical and more widely accepted alternative to gelatin derived from mammalian sources”. ( See abstract). Therefore, it would have been prima facie obvious to one with ordinary skill in the art at the time the invention was filed to substitute the source of gelatin from mammalian to fish. Because Sghayyar et al state that “ Fish gelatin has been recognized as a safer, economical and more widely accepted alternative to gelatin derived from mammalian sources” providing an ordinary skill in the art with the motivation to switch the source of gelatin from porcine to fish. In other words, instant claims would have been obvious to one of ordinary skill in the art, as the recited limitation is an example of substituting one known element for another known element, the elements having equivalent effect. According to the MPEP, the substitution is considered obvious, absent showing that the result of the substitution yields more than predictable results. See MPEP 2143(I)(B).
Conclusion
No claims is 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 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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to FATIMAH KHALAF MATALKAH whose telephone number is (703)756-5652. The examiner can normally be reached Monday-Friday,7:30 am-4:30 pm EST.
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/FATIMAH KHALAF MATALKAH/ Examiner, Art Unit 1638
/Tracy Vivlemore/ Supervisory Primary Examiner, Art Unit 1638
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