Viral vector delivery methods, systems, and applications for passivation of implantable neural electrodes

Abstract

The application discloses a virus carrier delivery method, system and application for preventing implantable neural electrode passivation, which comprises the following steps: firstly, a delivery structure is arranged on an implantable neural electrode for accommodating a virus carrier before or after implantation; a recombinant nucleic acid sequence of the virus carrier comprises a gene expression cassette, and the gene expression cassette comprises a cell type related promoter and a functional gene; then, the electrode is implanted into brain tissue to locally release the virus carrier; and finally, the virus carrier is used to transduce target glial cells, the cell type related promoter is used to make the functional gene mainly expressed in astrocytes and / or microglia, and an expression product of the functional gene is used to regulate inflammatory response, glial cell state and extracellular matrix, so as to reduce the thickness and compactness of a glial scar.

Description

Technical Field

[0001] This invention relates to the fields of biomedical engineering, brain-computer interface, viral vector delivery and neuroimmune regulation, and particularly to a method, system and application of viral vector delivery that resists the passivation of implanted neural electrodes. Background Technology

[0002] Implantable neural electrodes are widely used in fields such as brain-computer interfaces (BCI) and deep brain stimulation (DBS). Implantable electrodes can record neural activity and provide local stimulation at a high temporal resolution. However, after long-term implantation, tissue damage, release of inflammatory factors, microglia activation and migration, reactive proliferation of astrocytes, and extracellular matrix deposition inevitably occur around the electrodes, eventually forming a glial scar layer at the electrode-tissue interface.

[0003] The thickness and density of glial scars increase the physical distance and electrical isolation between the recording site and nearby neurons, gradually increasing the interface impedance, decreasing the signal-to-noise ratio of neural signals, reducing the number of effective recording units, and potentially causing an increase in the stimulation threshold and unstable neural modulation effects. This leads to long-term passivation of brain-computer interface electrodes and a limited service life.

[0004] For defects in glial scars around electrodes, existing technologies mainly reduce tissue damage, mechanical stimulation, and inflammatory responses caused by implantation by improving electrode materials and structures, using local coatings and sustained-release of anti-inflammatory drugs or neurotrophic factors, and optimizing surgical paths, implantation speeds, and implantation support structures. While these existing technologies can reduce acute inflammatory responses to some extent and even inhibit subsequent glial scar formation to some degree, they generally cannot directly and continuously intervene in the thickness and density of glial scars.

[0005] Chinese invention patent application No. 202510334859.4, filed on March 20, 2025, discloses a medium material for brain-computer interfaces, brain-spinal interfaces, or eye-computer interfaces and its application. The medium material includes a 3D cell layer; the 3D cell layer is prepared from a membrane matrix and cells; the cells are selected from autologous oral mucosal epithelial cells, allogeneic umbilical cord mesenchymal stem cells, or allogeneic amniotic mesenchymal stem cells. This design aims to use this medium material to encapsulate a chip before implantation, reducing the immune rejection reaction between the implanted chip and human tissue, thereby reducing stimulation of brain tissue by the implanted chip and preventing the formation of glial scar tissue. However, it has the following drawbacks:

[0006] First, this design is intended for implanted chips, not implanted neural electrodes;

[0007] Secondly, the design aims to avoid the formation of glial scar tissue, rather than focusing on reducing the thickness or density of glial scars, in order to avoid a gradual increase in surface impedance and a decrease in the signal-to-noise ratio of neural signals.

[0008] The information disclosed in this background section is intended only to enhance understanding of the overall background of this application and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0009] The purpose of this invention is to overcome the defects and problems of existing technologies that cannot directly reduce the thickness or density of glial scars, and to provide a method, system and application for delivering viral vectors that can directly reduce the thickness or density of glial scars and resist the passivation of implanted neural electrodes.

[0010] To achieve the above objectives, the technical solution of the present invention is: a method for delivering a viral vector that resists the passivation of implantable neural electrodes, the method comprising the following steps:

[0011] Step 1: First, a delivery structure is set on the implantable neural electrode. This delivery structure is used to load, contain, deliver and / or release a viral vector. The recombinant nucleic acid sequence of the viral vector includes at least one gene expression cassette, which includes at least one cell type-related promoter and at least one functional gene. The viral vector enters the delivery structure either before or after implantation.

[0012] Step 2: First, implant the implantable neural electrode into the brain tissue, and then release the viral vector locally at the electrode-brain tissue interface.

[0013] Step 3: After release, the virus vector first transduces the target glial cells, which are astrocytes and / or microglia. Then, the cell type-related promoter drives the expression of functional genes in the target glial cells. The expression products of the functional genes then regulate the inflammatory response, glial cell status, and extracellular matrix to reduce the thickness and density of glial scars.

[0014] In the first step, the delivery structure refers to any one or any combination of the following:

[0015] The first method involves creating microporous structures, microfluidic channels, or liquid reservoirs on or inside the electrode surface to contain the viral vector.

[0016] The second method involves encapsulating the viral vector by applying a porous polymer coating, a hydrogel sustained-release layer, a biodegradable polymer coating, an electroresponsive release coating, a magnetically responsive release coating, or a thermosensitive release coating to the electrode surface.

[0017] In the first step, the viral vector is any one of adeno-associated virus vector, lentiviral vector, herpes simplex virus vector, or any one of the engineered forms of the aforementioned viral vectors.

[0018] The adeno-associated virus vector is used in the following manner:

[0019] For astrocytes, use natural serotypes such as AAV5 or AAV11, or engineered adeno-associated virus vector AAV-F which has astrocyte transduction advantage;

[0020] For microglia, AAV9 from the natural serotype or the engineered adeno-associated virus vector AAV9-YAFGGEG, which has advantages in microglia transduction, is selected.

[0021] In the first step, the target cells are astrocytes:

[0022] The cell type-related promoters are GFAP promoter, gfaABC1D promoter, ALDH1L1 promoter, SLC1A3 promoter or other astrocyte-related promoters;

[0023] The functional genes are IL-10, ChABC, L1CAM or other genes, and these other genes refer to genes related to anti-inflammation, matrix degradation, nerve adhesion or repair support.

[0024] In the first step, the target cells are microglia:

[0025] The cell type-related promoters are Iba1 promoter, CD11b promoter, CX3CR1 promoter, TMEM119 promoter, P2RY12 promoter, or other microglia-related promoters;

[0026] The functional gene is IL-10, Arg1, STAT6 or other genes, where the other genes refer to functional genes with anti-inflammatory or repair phenotypes.

[0027] In the first step, when there are two or more types of viral vectors, the target glial cell types corresponding to each viral vector may be the same or different, and the target glial cell types are selected from astrocytes and microglia.

[0028] Subsequently, in the second step, all viral vectors are released either synchronously or in stages; the staged release is controlled by the delivery structure, including any one of partitioned loading, layered coating, materials with different degradation rates, or different microfluidic channels.

[0029] In the first step, the gene expression cassette also includes optional enhancers, miRNA detargeting elements, posttranscriptional regulatory elements, polyA signaling elements, and non-therapeutic marker elements;

[0030] The non-therapeutic labeling element includes one or more of the following: fluorescent protein-coding genes, bioluminescent reporter genes, immunoepitope tag coding sequences, or other detectable labeling sequences.

[0031] A viral vector delivery system for resisting passivation of implantable neural electrodes, the system being an implantable neural electrode with a delivery structure, wherein the delivery structure is used to load, contain, deliver and / or release a viral vector, the recombinant nucleic acid sequence of the viral vector including at least one gene expression cassette, the gene expression cassette including at least one cell type-related promoter and at least one functional gene.

[0032] Application of a viral vector delivery system for resisting the passivation of implantable neural electrodes, wherein the system is the aforementioned viral vector delivery system for resisting the passivation of implantable neural electrodes; the application refers to the application of the system in the preparation of neural implantable devices for reducing the increase of interfacial impedance of implantable neural electrodes, maintaining the quality of neural signals, reducing the increase of stimulation threshold, or extending the service life of brain-computer interface electrodes.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0034] 1. This invention discloses a method, system, and application for delivering a viral vector to resist the passivation of implantable neural electrodes. First, a delivery structure is set on the implantable neural electrode. This delivery structure loads, contains, delivers, and / or releases a viral vector. The recombinant nucleic acid sequence of the viral vector includes a gene expression cassette, which includes a cell type-related promoter and a functional gene. The implantable neural electrode is then implanted into brain tissue. The viral vector is then locally released at the electrode-brain tissue interface. The viral vector transduces target glial cells. The cell type-related promoter causes the functional gene to be expressed primarily in astrocytes and / or microglia (i.e., the functional gene is mainly or preferentially expressed in astrocytes or microglia surrounding the electrode, while expression is relatively low in neurons, oligodendrocytes, and other non-target cells). The expression products of the functional gene further regulate the inflammatory response, glial cell state, and extracellular matrix, thereby reducing the thickness and density of glial scars. The advantages of this design include:

[0035] Firstly, this design directly reduces the thickness and density of the glial scar layer, improves ion conduction and electrical coupling at the electrode-tissue interface, thereby helping to reduce the rate of increase in electrode interface impedance and maintain neural signal recording performance. While protecting tissue repair function, it reduces the increase in electrode impedance and signal attenuation in the chronic phase, resulting in a more reasonable biological endpoint.

[0036] Secondly, this design can directly reduce the thickness of glial scars. The preferred evaluation index is that the radial thickness of the glial scar layer is within 50 μm, or that it is reduced by more than 20% compared with the control group of ordinary implanted neural electrodes.

[0037] Thirdly, this design can directly reduce the density of glial scars. The preferred evaluation index is that the proportion of GFAP positive area and / or CSPG positive area in the 0-50μm range from the electrode-tissue interface is reduced by more than 20% compared with the control group of ordinary implanted nerve electrodes.

[0038] Fourthly, the selection of viral vectors, cell type-related promoters, and functional genes can directly infect and regulate astrocytes and / or microglia, thereby inhibiting excessive inflammatory responses and abnormal glial cell proliferation. This shifts the glial response from a state of persistent pro-inflammatory and excessive encapsulation to a state of low inflammation, support, and structural stability, promoting the formation of thin, stable glial scar interfaces with low inflammatory levels, rather than simply clearing all glial cells. Simultaneously, it enhances the expression selectivity of functional genes in target glial cells, reducing the impact on neurons and other non-target cells.

[0039] Fifthly, the local release in this invention refers to the deloading of the viral vector through a delivery structure on the implanted neural electrode, followed by its release. This design allows the viral vector to be released directly at the electrode-brain tissue interface, reducing diffusion to brain tissue far from the electrode. The recruitment of glial cells around the electrode and the selective expression of glial cell-related promoters can further concentrate the expression and function of functional genes near the electrode-tissue interface.

[0040] Sixth point: This invention can reduce the expression levels of inflammation-related indicators such as Iba1 and CD68 around the electrode, as well as pro-inflammatory factors such as IL-1β, TNF-α, and IL-6, compared to the control group of ordinary implanted neural electrodes, preferably by more than 20%, thereby achieving the basic requirement of low inflammation level.

[0041] Seventh point: During the chronic observation phase after implantation, such as from week 4 to week 8 or longer, the variation in glial scar thickness and electrode interface impedance is preferably no more than 20%, and the performance is stable.

[0042] Therefore, this invention is not only highly targeted, capable of directly reducing the thickness or density of glial scars and preventing electrode passivation, but also capable of local release, reducing non-specific effects, so as to facilitate the formation of a thin, stable, and low-inflammatory glial scar interface.

[0043] 2. In the present invention, a method, system, and application for delivering a viral vector to resist the passivation of implantable neural electrodes, there are limitations on the viral vector, cell type-related promoters, and functional genes. Based on the primary target cells being astrocytes or microglia, not only is the viral vector optimized, but the combination of cell type-related promoters and functional genes is also optimized to achieve precise regulation, as detailed below:

[0044] First, precise cell type targeting: Viral vectors have the advantage of glial cell transduction, with promoters related to astrocytes or microglia directly controlling the expression of functional genes primarily in the corresponding glial cells; at the same time, optional miRNA detargeting elements can inhibit the expression of functional genes in non-target cells, thereby improving the overall transduction and expression selectivity in astrocytes and / or microglia, reducing spatial and cell type nonspecific effects compared to drug diffusion;

[0045] Secondly, precise targeting of scar formation stages: Different functional genes target different pathological processes. For example, IL-10, Arg1, and STAT6 mainly regulate inflammation and microglial state; ChABC mainly reduces scar matrix such as CSPGs; and L1CAM mainly improves neuronal adhesion and interfacial coupling, thus controlling different stages of scar formation. Furthermore, viral vectors loaded with specific functional genes, combined with different delivery structures, such as sustained-release materials with different degradation rates, and electro-, magnetic-, or thermo-sensitive release structures, can release different viral vectors at different time stages, further enhancing the precision of scar formation stages.

[0046] Therefore, the present invention can precisely control scar formation.

[0047] 3. In the present invention, a viral vector delivery method, system, and application for preventing the passivation of implantable neural electrodes addresses the challenges of long-term stable operation of brain-computer interface electrodes. Relying solely on a single-use drug coating or short-term administration is insufficient to cover the chronic glial reaction period of several weeks to months or even longer. Furthermore, traditional drug-release strategies suffer from drawbacks such as short duration of action, off-target effects due to drug diffusion, and potential toxic side effects with long-term use. However, this invention is entirely different. After transducing target glial cells, the viral vector in this invention enables the continuous expression of functional genes and the continuous production of functional proteins within the target cells (after AAV transduction, the functional genes carried by the vector can be continuously expressed within the cells, enabling the target cells to continuously produce functional proteins such as IL-10 and ChABC for a prolonged period, lasting for several months, with the longest observation period up to 12 months), without relying on the continuous release of drugs pre-loaded in the delivery structure. Compared to the problems of gradual degradation, diffusion, and depletion of active ingredients associated with drug-release, this invention can cover the chronic glial reaction phase of several weeks to months or even longer with a single local delivery, covering the critical time window of glial scar formation and chronic electrode passivation, and providing a longer-lasting local intervention capability compared to traditional drug-release methods. Therefore, the present invention has long-term effectiveness.

[0048] 4. In the present invention, a method, system, and application for delivering a viral vector to resist the passivation of implantable neural electrodes, the gene expression cassette further includes optional enhancers, miRNA detargeting elements, post-transcriptional regulatory elements, polyA signals, and non-therapeutic labeling elements. The enhancers, miRNA detargeting elements, post-transcriptional regulatory elements, and polyA signals are used to regulate the intensity, specificity, and stability of functional gene expression; the non-therapeutic labeling elements are used to display and evaluate the transduction and expression of the viral vector, and to assist in evaluating the transduction of the viral vector in the tissue surrounding the electrode. Thus, overall, anti-inflammatory effects, scar matrix regulation, enhanced neural adhesion, and optional labeling verification are achieved within the same system, forming an integrated "delivery-regulation-verification-evaluation" anti-passivation scheme. Therefore, the present invention can achieve multifunctional integration.

[0049] 5. In the present invention, a method, system, and application for delivering a viral vector to resist the passivation of implantable neural electrodes, the delivery structure preferably includes any one or any combination of the following: First, a microporous structure, microfluidic channel, or reservoir is provided on or inside the electrode surface to contain the viral vector; Second, a porous polymer coating, hydrogel sustained-release layer, biodegradable polymer coating, electroresponsive release coating, magnetically responsive release coating, or thermosensitive release coating is provided on the electrode surface to encapsulate the viral vector. The design of these various delivery structures not only enables the local release of the viral vector at the electrode-brain tissue interface, reducing the thickness or density of glial scars, but also allows for the collaborative release of the viral vector during the release phase, achieving staged release for better regulatory effects. Furthermore, it avoids the need for additional large-volume drug delivery devices, is compatible with existing implantable neural electrode platforms, and exhibits good interface coupling. Therefore, the present invention, through the design of the delivery structure, not only helps to reduce the thickness or density of glial scars but also improves the regulatory effect on scar formation, exhibiting good interface coupling. Attached Figure Description

[0050] Figure 1 This is a flowchart illustrating the present invention.

[0051] Figure 2 This is a schematic diagram of the mechanism of action of the present invention.

[0052] Figure 3 This is a schematic diagram of a delivery structure in this invention.

[0053] Figure 4 This is a schematic diagram of another delivery structure in this invention. Detailed Implementation

[0054] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0055] See Figure 1 — Figure 4 A method for delivering a viral vector that resists the passivation of implantable neural electrodes, the method comprising the following steps:

[0056] Step 1: First, a delivery structure is set on the implantable neural electrode. This delivery structure is used to load, contain, deliver, and / or release a viral vector. The recombinant nucleic acid sequence of the viral vector includes at least one gene expression cassette. The gene expression cassette includes at least one cell type-related promoter and at least one functional gene (when there are multiple functional genes, the multiple functional genes can be set in one or more gene expression cassettes of the same viral vector, or they can be set in different viral vectors and delivered together). The viral vector enters the delivery structure either before or after implantation.

[0057] Step 2: First, implant the implantable neural electrode into the brain tissue, and then release the viral vector locally at the electrode-brain tissue interface.

[0058] Step 3: After release, the virus vector first transduces the target glial cells, which are astrocytes and / or microglia. Then, the cell type-related promoter drives the expression of functional genes in the target glial cells. The expression products of the functional genes then regulate the inflammatory response, glial cell status, and extracellular matrix to reduce the thickness and density of glial scars.

[0059] In the first step, the delivery structure refers to any one or any combination of the following:

[0060] The first method involves creating microporous structures, microfluidic channels, or liquid reservoirs on or inside the electrode surface to contain the viral vector.

[0061] The second method involves encapsulating the viral vector by applying a porous polymer coating, a hydrogel sustained-release layer, a biodegradable polymer coating, an electroresponsive release coating, a magnetically responsive release coating, or a thermosensitive release coating to the electrode surface.

[0062] In the first step, the viral vector is any one of adeno-associated virus vector, lentiviral vector, herpes simplex virus vector, or any one of the engineered forms of the aforementioned viral vectors.

[0063] The adeno-associated virus vector is used in the following manner:

[0064] For astrocytes, use natural serotypes such as AAV5 or AAV11, or engineered adeno-associated virus vector AAV-F which has astrocyte transduction advantage;

[0065] For microglia, AAV9 from the natural serotype or the engineered adeno-associated virus vector AAV9-YAFGGEG, which has advantages in microglia transduction, is selected.

[0066] In the first step, the target cells are astrocytes:

[0067] The cell type-related promoters are GFAP promoter, gfaABC1D promoter, ALDH1L1 promoter, SLC1A3 promoter or other astrocyte-related promoters;

[0068] The functional genes are IL-10, ChABC, L1CAM or other genes, and these other genes refer to genes related to anti-inflammation, matrix degradation, nerve adhesion or repair support.

[0069] In the first step, the target cells are microglia:

[0070] The cell type-related promoters are Iba1 promoter, CD11b promoter, CX3CR1 promoter, TMEM119 promoter, P2RY12 promoter, or other microglia-related promoters;

[0071] The functional gene is IL-10, Arg1, STAT6 or other genes, where the other genes refer to functional genes with anti-inflammatory or repair phenotypes.

[0072] In the first step, when there are two or more types of viral vectors, the target glial cell types corresponding to each viral vector may be the same or different, and the target glial cell types are selected from astrocytes and microglia.

[0073] Subsequently, in the second step, all viral vectors are released either synchronously or in stages; the staged release is controlled by the delivery structure, including any one of partitioned loading, layered coating, materials with different degradation rates, or different microfluidic channels.

[0074] In the first step, the gene expression cassette further includes optional enhancers, miRNA detargeting elements, posttranscriptional regulatory elements, polyA signaling elements, or non-therapeutic marker elements; the non-therapeutic marker elements include one or more of fluorescent protein-coding genes, bioluminescent reporter genes, immunoepitope tag coding sequences, or other detectable marker sequences.

[0075] A viral vector delivery system for resisting passivation of implantable neural electrodes, the system being an implantable neural electrode with a delivery structure, wherein the delivery structure is used to load, contain, deliver and / or release a viral vector, the recombinant nucleic acid sequence of the viral vector including at least one gene expression cassette, the gene expression cassette including at least one cell type-related promoter and at least one functional gene.

[0076] Application of a viral vector delivery system for resisting the passivation of implantable neural electrodes, wherein the system is the aforementioned viral vector delivery system for resisting the passivation of implantable neural electrodes; the application refers to the application of the system in the preparation of neural implantable devices for reducing the increase of interfacial impedance of implantable neural electrodes, maintaining the quality of neural signals, reducing the increase of stimulation threshold, or extending the service life of brain-computer interface electrodes.

[0077] The supplementary technical features of this invention are as follows:

[0078] The implantable neural electrode of this invention is used to implant into the target brain region and form an electrical interface with the surrounding neural tissue. The electrode array on the implantable neural electrode contains multiple independent electrode channels, some of which are used for neural signal recording and some for electrical stimulation modulation. It can also be dynamically configured by the control system to achieve the synergy of recording, stimulation and local delivery functions.

[0079] Example 1:

[0080] See Figure 1 — Figure 2 A method for delivering a viral vector that resists the passivation of implantable neural electrodes, the method comprising the following steps:

[0081] Step 1: First, a delivery structure is set on the implanted neural electrode. This delivery structure is used to load, contain, deliver and / or release a viral vector (preferably any one of adeno-associated virus vector, lentiviral vector, herpes simplex virus vector, or any engineered form of the aforementioned viral vector). The recombinant nucleic acid sequence of the viral vector includes at least one gene expression cassette. The gene expression cassette includes at least one cell type-related promoter and at least one functional gene (when there are multiple functional genes, the multiple functional genes can be set in one or more gene expression cassettes of the same viral vector, or they can be set in different viral vectors and delivered together).

[0082] Step 2: First, implant the implantable neural electrode into the brain tissue, and then release the viral vector locally at the electrode-brain tissue interface.

[0083] Step 3: After release, the virus vector first transduces the target glial cells, which are astrocytes and / or microglia. Then, the cell type-related promoter drives the expression of functional genes in the target glial cells. The expression products of the functional genes then regulate the inflammatory response, glial cell status, and extracellular matrix to reduce the thickness and density of glial scars.

[0084] A viral vector delivery system for resisting passivation of implantable neural electrodes, the system being an implantable neural electrode with a delivery structure, wherein the delivery structure is used to load, contain, deliver and / or release a viral vector, the recombinant nucleic acid sequence of the viral vector including at least one gene expression cassette, the gene expression cassette including at least one cell type-related promoter and at least one functional gene.

[0085] Application of a viral vector delivery system for resisting the passivation of implantable neural electrodes, wherein the system is the aforementioned viral vector delivery system for resisting the passivation of implantable neural electrodes; the application refers to the application of the system in the preparation of neural implantable devices for reducing the increase of interfacial impedance of implantable neural electrodes, maintaining the quality of neural signals, reducing the increase of stimulation threshold, or extending the service life of brain-computer interface electrodes.

[0086] Example 2:

[0087] The basic content is the same as in Example 1, except that:

[0088] The adeno-associated virus (AAV) vectors are applied as follows: For astrocytes, AAV5 or AAV11 from natural serotypes, or the engineered AAV-F vector with astrocyte transduction advantage, are selected. These viral vectors act directly on astrocytes and scar-related extracellular matrix, and are more directly related to reducing the thickness and density of glial scars. For microglia, AAV9 from natural serotypes, or the engineered AAV9-YAFGGEG vector with microglia transduction advantage, are selected. These viral vectors mainly target the upstream inflammatory response mediated by microglia, indirectly reducing subsequent astrocyte activation and extracellular matrix deposition.

[0089] The preferred schemes for the aforementioned natural serotypes are more conducive to delivering functional genes to target glial cells, increasing the tendency and efficiency of viral vectors entering target glial cells. The main advantage of using engineered or mutant vectors with glial cell transduction advantages is that by changing the capsid structure, the transduction efficiency of conventional natural serotypes to target glial cells is further improved. This is especially suitable for microglia where natural AAV is difficult to transduce effectively, and is more conducive to delivering functional genes to target glial cells, thus increasing the tendency and efficiency of viral vectors entering target glial cells.

[0090] Example 3:

[0091] The basic content is the same as in Example 1, except that:

[0092] In the first step, for astrocytes: the cell type-related promoter is the GFAP promoter, gfaABC1D promoter, ALDH1L1 promoter, SLC1A3 promoter, or other astrocyte-related promoters; the functional gene is IL-10, ChABC, L1CAM, or other genes, where other genes refer to genes related to anti-inflammation, matrix degradation, neural adhesion, or repair support.

[0093] Among them, IL-10 is used to inhibit local pro-inflammatory responses, ChABC is used to degrade chondroitin sulfate proteoglycans (CSPGs) and reduce glial scar barriers, and L1CAM is used to enhance neuronal adhesion and neurite regeneration, thereby improving neuron-electrode functional coupling around the electrode.

[0094] Further preferred is any of the following combinations: AAV5 or AAV11 viral vector + GFAP or gfaABC1D promoter + IL-10 or ChABC functional gene + optional miR-124 detargeting element + WPRE + polyA signal; wherein, the GFAP or gfaABC1D promoter enables the functional gene to be expressed mainly in astrocytes; the miR-124 target sequence can inhibit the residual expression of the functional gene in neurons; WPRE and polyA signal are used to improve the stability and expression efficiency of mRNA.

[0095] Example 4:

[0096] The basic content is the same as in Example 1, except that:

[0097] In the first step, targeting microglia: the cell type-related promoters are Iba1 promoter, CD11b promoter, CX3CR1 promoter, TMEM119 promoter, P2RY12 promoter, or other microglia-related promoters; the functional genes are IL-10, Arg1, STAT6, or other genes, where "other genes" refers to functional genes that promote anti-inflammatory or repair phenotypes. The purpose of this design is to drive or maintain the transformation of microglia into a low-pro-inflammatory, high-repair functional state, reducing the sustained induction of reactive astrocyte proliferation by chronic inflammation.

[0098] Further preferred is any of the following combinations: AAV9 or an engineered AAV viral vector with proven microglia transduction advantage + Iba1-related promoter + IL-10, Arg1, or STAT6 functional genes + optional miR-9 and miR-129-2-3p detargeting elements + WPRE + polyA signaling, wherein the Iba1-related promoter enables preferential expression of functional genes in microglia; and the miR-9 and miR-129-2-3p target sequences are used to suppress residual expression in non-microglia.

[0099] Example 5:

[0100] The basic content is the same as in Example 1, except that:

[0101] In the first step, when there are two or more viral vectors, at least one viral vector targets astrocytes (preferably carrying anti-inflammatory functional genes and / or glial scar-related extracellular matrix regulatory genes, such as IL-10, TGF-β, or ChABC, which are used to reduce local inflammation and decrease glial scar-related extracellular matrix deposition, respectively), while the other viral vector targets microglia (preferably carrying regulatory genes that promote anti-inflammatory or repair phenotypes, such as IL-10, Arg1, or STAT6, which are used to influence the inflammatory response and repair-related status of microglia). After the above viral vectors are delivered together, combined intervention can be performed on astrocytes, microglia, and scar-related extracellular matrix.

[0102] Subsequently, in the second step, all viral vectors are released either simultaneously or in stages; the staged release is controlled by the delivery structure, including any one of the following: partitioned loading, layered coating, materials with different degradation rates, or different microfluidic channels. Furthermore, two types of viral vectors can be loaded simultaneously or partitionedly in the same electrode delivery structure.

[0103] Example 6:

[0104] The basic content is the same as in Example 1, except that:

[0105] In specific implementation, the present invention preferably adopts a basic scheme + an advanced scheme + a high-order scheme in sequence.

[0106] The basic protocol works by combining anti-inflammatory measures with scar matrix regulation. It involves locally releasing AAV5, AAV11, or engineered AAV cells via electrodes. These cells carry astrocyte-related promoters and functional genes such as IL-10 and ChABC, replacing short-acting anti-inflammatory drugs and exogenous scar-degrading enzymes to improve the thickness and density of glial scars. Furthermore, the viral vector in this protocol does not only transduce astrocytes; the genes it carries, such as the astrocyte-related promoters, are used to ensure that functional genes are primarily or preferentially expressed in astrocytes, improving cell type selectivity. However, there is also a probability of expression in other cells. For example, the expression products of IL-10 and ChABC can also act on surrounding microglia and the extracellular matrix. Therefore, the basic protocol is a protocol that primarily targets astrocytes for expression while simultaneously regulating the local microenvironment.

[0107] The advanced approach further introduces neural adhesion-related genes such as L1CAM into the basic approach to enhance the adhesion and repair support capabilities of neurons at the interface around the electrodes.

[0108] The advanced protocol employs multi-AAV vector co-delivery (i.e., using multiple viral vectors for co-delivery, with each viral vector carrying at least one gene expression cassette to regulate different cell types or different pathological processes), while simultaneously regulating astrocytes and microglia to achieve synergistic effects of anti-inflammatory, scar matrix regulation, neural adhesion, and immune repair phenotype induction.

[0109] Therefore, the basic and advanced protocols prioritize astrocytes as the primary cells for the expression of functional genes, which are mainly expressed in astrocytes. The advanced protocol further introduces microglia-related promoters and corresponding viral vectors, enabling some functional genes to also be expressed primarily in microglia. This not only indirectly affects microglia but also increases the direct intervention on the inflammatory response and repair-related states of microglia.

[0110] Example 7:

[0111] The basic content is the same as in Example 1, except that:

[0112] The delivery structure preferably includes a reservoir, a microfluidic channel, and a release outlet. The reservoir is used to contain the viral vector, and the microfluidic channel is disposed inside the base of the implantable neural electrode and communicates with both the reservoir and the release outlet for delivering the viral vector. The release outlet is preferably located around the electrode recording / stimulation site, at the tip, and / or in the vicinity of the insertion trajectory for releasing the viral vector to the vicinity of the electrode-tissue interface.

[0113] Please see Figure 3 The viral vector in the reservoir enters the microfluidic channel connected to it and is transported along the microfluidic channel located inside the electrode substrate. It is then released near the recording / stimulation site through the release outlet connected to the microfluidic channel, thereby achieving local delivery of the viral vector near the electrode-tissue interface.

[0114] Example 8:

[0115] The basic content is the same as in Example 1, except that:

[0116] The delivery structure preferably comprises a porous polymer coating, a hydrogel sustained-release coating, a biodegradable polymer coating, an electroresponsive release coating, a magnetically responsive release coating, or a thermosensitive release coating on the electrode surface to encapsulate the viral vector. More preferably, the delivery structure is disposed around the electrode recording / stimulation site, at the tip, and / or in the region adjacent to the insertion trajectory.

[0117] Please see Figure 4The viral vector is loaded into a coating disposed on the surface of the implantable neural electrode substrate via adsorption, embedding, and / or reversible immobilization. This coating avoids the recording / stimulation sites, keeping the electrode surface at the recording / stimulation sites exposed. After electrode implantation, tissue fluid enters the coating, and the viral vector is gradually released to the vicinity of the recording / stimulation sites through desorption, diffusion, and / or material degradation, thereby achieving localized release of the viral vector near the electrode-tissue interface.

[0118] The above description is only a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. Any equivalent modifications or changes made by those skilled in the art based on the content disclosed in the present invention should be included within the scope of protection set forth in the claims.

Claims

1. A method for delivering a viral vector that resists passivation of implanted neural electrodes, characterized in that: The method includes the following steps: Step 1: First, a delivery structure is set on the implantable neural electrode. This delivery structure is used to load, contain, deliver and / or release a viral vector. The recombinant nucleic acid sequence of the viral vector includes at least one gene expression cassette, which includes at least one cell type-related promoter and at least one functional gene. The viral vector enters the delivery structure either before or after implantation. Step 2: First, implant the implantable neural electrode into the brain tissue, and then release the viral vector locally at the electrode-brain tissue interface. Step 3: After release, the virus vector first transduces the target glial cells, which are astrocytes and / or microglia. Then, the cell type-related promoter drives the expression of functional genes in the target glial cells. The expression products of the functional genes then regulate the inflammatory response, glial cell status, and extracellular matrix to reduce the thickness and density of glial scars.

2. The method for delivering a viral vector to resist the passivation of implantable neural electrodes according to claim 1, characterized in that: In the first step, the delivery structure refers to any one or any combination of the following: The first method involves creating microporous structures, microfluidic channels, or liquid reservoirs on or inside the electrode surface to contain the viral vector. The second method involves encapsulating the viral vector by applying a porous polymer coating, a hydrogel sustained-release layer, a biodegradable polymer coating, an electroresponsive release coating, a magnetically responsive release coating, or a thermosensitive release coating to the electrode surface.

3. A method for delivering a viral vector to resist the passivation of implantable neural electrodes according to claim 1 or 2, characterized in that: In the first step, the viral vector is any one of adeno-associated virus vector, lentiviral vector, herpes simplex virus vector, or any one of the engineered forms of the aforementioned viral vectors.

4. The method for delivering a viral vector to resist the passivation of implantable neural electrodes according to claim 3, characterized in that: The adeno-associated virus vector is used in the following manner: For astrocytes, use natural serotypes such as AAV5 or AAV11, or engineered adeno-associated virus vector AAV-F which has astrocyte transduction advantage; For microglia, AAV9 from the natural serotype or the engineered adeno-associated virus vector AAV9-YAFGGEG, which has advantages in microglia transduction, is selected.

5. A method for delivering a viral vector to resist the passivation of implantable neural electrodes according to claim 1 or 2, characterized in that: In the first step, the target cells are astrocytes: The cell type-related promoters are GFAP promoter, gfaABC1D promoter, ALDH1L1 promoter, SLC1A3 promoter or other astrocyte-related promoters; The functional genes are IL-10, ChABC, L1CAM or other genes, and these other genes refer to genes related to anti-inflammation, matrix degradation, nerve adhesion or repair support.

6. A method for delivering a viral vector to resist the passivation of implantable neural electrodes according to claim 1 or 2, characterized in that: In the first step, the target cells are microglia: The cell type-related promoters are Iba1 promoter, CD11b promoter, CX3CR1 promoter, TMEM119 promoter, P2RY12 promoter, or other microglia-related promoters; The functional gene is IL-10, Arg1, STAT6 or other genes, where the other genes refer to functional genes with anti-inflammatory or repair phenotypes.

7. A method for delivering a viral vector to resist the passivation of implantable neural electrodes according to claim 1 or 2, characterized in that: In the first step, when there are two or more types of viral vectors, the target glial cell types corresponding to each viral vector may be the same or different, and the target glial cell types are selected from astrocytes and microglia. Subsequently, in the second step, all viral vectors are released either simultaneously or in stages. The staged release is controlled by a delivery structure, including any one of partitioned loading, layered coating, materials with different degradation rates, or different microfluidic channels.

8. A method for delivering a viral vector to resist the passivation of implantable neural electrodes according to claim 1 or 2, characterized in that: In the first step, the gene expression cassette also includes optional enhancers, miRNA detargeting elements, posttranscriptional regulatory elements, polyA signaling elements, and non-therapeutic marker elements; The non-therapeutic labeling element includes one or more of the following: fluorescent protein-coding genes, bioluminescent reporter genes, immunoepitope tag coding sequences, or other detectable labeling sequences.

9. A viral vector delivery system resistant to implantable neural electrode passivation, characterized in that: The system is an implantable neural electrode with a delivery structure as described in claim 1 or 2, and the delivery structure is used to load, contain, deliver and / or release a viral vector, wherein the recombinant nucleic acid sequence of the viral vector includes at least one gene expression cassette, the gene expression cassette including at least one cell type-related promoter and at least one functional gene.

10. The application of a viral vector delivery system resistant to implantable neural electrode passivation, characterized in that: The system is a viral vector delivery system for implantable neural electrodes as described in claim 9; The application refers to the use of the system in the preparation of neural implantation devices for reducing the increase in interface impedance of implantable neural electrodes, maintaining the quality of neural signals, reducing the increase in stimulation threshold, or extending the service life of brain-computer interface electrodes.

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