Patent Application
20210038818
The present invention relates to an injector and a method of injecting a solution containing biomolecules into a cell nucleus of an injection target using the same.
Regarding injectors for injecting a drug solution into a living body or the like, there are catheters including an injection needle and a drive source for transporting a drug solution into an injection target in addition to a needle syringe that performs injection through an injection needle and a needleless syringe that performs injection without using an injection needle.
Among these, a needleless syringe may be configured to inject an injection component by applying a pressure to an accommodation chamber in which an injection solution is accommodated using a pressurized gas, a spring, or an electromagnetic force. For example, a configuration in which a plurality of nozzle holes are formed inside a syringe main body and a piston that is driven during injection is arranged to correspond to each nozzle hole may be used (Patent Document 1). With such a configuration, an injection solution is sprayed simultaneously from a plurality of nozzle holes and uniform injection into a target is realized. Then, a plasmid containing a luciferase gene can be injected into rats and cells can be transferred with high efficiency.
In addition, there is a form in which a pressurized gas is used as an injection power source for an injection solution in a needleless syringe. For example, a pressurization form in which a high pressure is instantaneously applied in the initial stage of injection, and the applied pressure is then gradually reduced over 40 to 50 msec may be exemplified (Patent Document 2).
However, there are no reports in which a solution containing biomolecules can be directly injected into a cell nucleus of an injection target by an injector with high efficiency. In addition, there are no reports focusing on conditions for injecting a solution containing biomolecules from an injector required for directly injecting a solution containing biomolecules into a cell nucleus of the injection target with high efficiency.
[Patent Document 1] Japanese Patent Application Publication. No. 2004-358234
The present invention has been made in view of such circumstances, and an object of the present invention is to provide an injector that can directly inject a solution containing biomolecules into a cell nucleus of an injection target with high efficiency and a method of directly injecting a solution containing biomolecules into a cell nucleus of an injection target using the injector with high efficiency.
The inventors conducted extensive studies and as a result, found that, in an injector in which a solution containing biomolecules is accommodated, by focusing on an injection speed of the solution containing biomolecules within a predetermined time from an injection start time of the solution containing biomolecules injected by the injector, the following injector can address the above problems, and thus completed the present invention. The present invention is as follows.
an accommodation unit for accommodating a solution containing biomolecules; and
a nozzle unit including an injection port through which the solution containing biomolecules flows and is injected into the injection target, the solution being pressurized,
wherein there is a time at which an injection speed of the solution containing biomolecules is 40 m/s or more between an injection start time of the solution containing biomolecules and a time of 0.20 ms.
wherein there is a time at which the injection speed of the solution containing biomolecules is 75 m/s or more between the injection start time of the solution containing biomolecules and a time of 0.20 ms.
wherein there is a time at which the injection speed of the solution containing biomolecules is 75 m/s or more between the injection start time of the solution containing biomolecules and a time of 0.15 ms.
According to the present invention, it is possible to provide an injector that can directly inject a solution containing biomolecules into a cell nucleus of an injection target with high efficiency and a method of directly injecting a solution containing biomolecules into a cell nucleus of an injection target using the injector with high efficiency.
The present invention includes an invention of an injector (first aspect) and an invention of a method of injecting a solution containing biomolecules to a cell nucleus of an injection target using the injector (second aspect).
<First Aspect>
The first aspect of the present invention is an injector that injects a solution containing biomolecules into an injection target from an injector main body without performing injection through a given structure in a state where the given structure is inserted into the injection target, the injector comprising: an accommodation unit for accommodating a solution containing biomolecules; and a nozzle unit including an injection port through which the solution containing biomolecules flows and is injected into the injection target, the solution being pressurized, wherein there is a time at which an injection speed of the solution containing biomolecules is 40 m/s or more between an injection start time of the solution containing biomolecules and a time of 0.20 ms.
In the injector according to the first aspect of the present invention, since there is a time at which the injection speed of the solution containing biomolecules is 40 m/s or more between the injection start time of the solution containing biomolecules and a time of 0.20 ms, it is possible to directly inject the solution containing biomolecules into a cell nucleus of the injection target with high efficiency.
Specifically, for example, when the injection target is cells in a mammalian individual (living body), there is a time at which the injection speed of the solution containing biomolecules is 40 m/s or more between the injection start time of the solution containing biomolecules and a time of 0.20 ms, and thus the solution containing biomolecules penetrates through the epidermis of the mammalian individual (living body), the cells are deformed due to a shear force when the solution is injected into the dermis, and the solution containing biomolecules is expected to be directly injected into the cell nucleus of the cells in the mammalian individual (living body) with high efficiency.
In this case, since the solution containing biomolecules is directly injected into a cell nucleus of the injection target with higher efficiency, preferably, there is a time at which the injection speed of the solution containing biomolecules is 75 m/s or more between the injection start time of the solution containing biomolecules and a time of 0.20 ms, and more preferably there a time at which the injection speed of the solution containing biomolecules is 75 m/s or more between the injection start time of the solution containing biomolecules and a time of 0.15 ms. In addition, for example, when the injection target is cells in a mammalian individual (living body), since the solution containing biomolecules is expected to be injected into the injection target without penetrating through the mammalian. individual (living body) itself, the injection speed of the solution containing biomolecules is preferably 250 m/s or less and more preferably 200 m/s or less between the injection start time of the solution containing biomolecules and a time of 0.20 ms. For example, when the injection target is cells in swine, and as a preferable form, when the injection target is cells in the skin of the abdomen, the injection speed is preferably 200 m/s or less. In addition, when. the injection target is cells in a rat, and as a preferable form, when the injection target is cells in the skin of the lumbar back, the injection speed is preferably 150 m/s or less.
In the first aspect of the present invention, biomolecules injected into the cell nucleus of the injection target are not particularly limited as long as they function in the cell nucleus or cells of the injection target when they are injected into the cell nucleus of the injection target. In addition, the biomolecules may be a natural product or artificially synthesized product. Examples thereof include nucleic acids or derivatives thereof; nucleosides, nucleotides or derivatives thereof; amino acids, peptides, proteins or derivatives thereof; lipids or derivatives thereof; metal ions; low-molecular-weight compounds or derivatives thereof; antibiotics; and vitamins or derivatives thereof. The nucleic acid may be DNA or RNA, and may include a gene. In examples to be described below, a free Cy3-labeled plasmid DNA is used as biomolecules.
The form of the biomolecules to be injected into the cell nucleus of the injection target and a solvent therefor are not particularly limited as long as biomolecules are stably present and there is no adverse effect such as destruction of the injection target or the cell nucleus of the injection target to be injected, and may be a free form, a form in which biomolecules are fixed to carriers such as nanoparticles, a modified form.
When DNA contains a gene, a design form in which the gene is contained in an expression cassette or expression vector may be exemplified. In addition, for example, the gene may be provided under control of a promoter suitable for the type of the injection target into which the DNA is injected and the injection site. That is, in any of the forms, a known genetic engineering technique can be used.
In the injector according to the first aspect of the present invention, “distal end side” refers to the side on which an injection port through which a solution containing biomolecules is injected from an injector is arranged, and “proximal end side” refers to the side opposite to the distal end side in the injector, and these terms do not limit specific locations or positions.
The injector according to the first aspect of the present invention injects a solution containing biomolecules to the injection target from an injector main body without performing injection through a given structure in the state where the given structure is inserted into the injection target. The injector according to the first aspect of the present invention may have, for example, a given structure such as a catheter for guiding a solution containing biomolecules from an injector main body to an injection target, for example, when a distance from the injector main body to the injection target is large. Therefore, the injector according to the first aspect of the present invention. may or may not have such a given structure. However, when the injector has such a given structure, a solution containing biomolecules is not injected into the injection target in the state where the given structure is inserted into the injection target.
In the injector according to the first aspect of the present invention, a driving unit for pressurizing a solution containing biomolecules is not particularly limited. The pressurization may be caused by, for example, a pressure generated when the pressure of the compressed gas is released, or a pressure generated by combustion of an explosive that is ignited by an ignition device. In addition, pressurization using an electromagnetic force, for example, pressurization using a linear electromagnetic actuator, may be used. Preferably, at least, a form in which a pressure generated by combustion of an explosive that is ignited by an ignition device is used, or any one of two other pressurization forms or a combination of them may be used.
When a form in which a pressure generated by combustion of an explosive that ignited by an ignition device is used for pressurization is used, the explosive may be, for example, any explosive among an explosive containing zirconium and potassium perchlorate (ZPP), an explosive containing titanium hydride and potassium perchlorate (THPP), an explosive containing titanium and potassium perchlorate (TiPP), an explosive containing aluminum and potassium perchlorate (APP), an explosive containing aluminum and bismuth oxide (ABO), an explosive containing aluminum and molybdenum oxide (AMO), an explosive containing aluminum and copper oxide (ACO), and an explosive containing aluminum and iron oxide (AFO) or an explosive composed of a plurality of combinations of these. Regarding a feature of these explosives, if the combustion products are gases in a high temperature state, since they do not contain gas components at room temperature, the combustion products after ignition immediately condense.
In addition, when the generated energy of a gas generating agent is used as injection energy, various gas generating agents used in a single base smokeless explosive, a gas generator for an airbag, and a gas generator for a seat belt pretensioner can be used as the gas generating agent.
In the injector according to the first aspect of the present invention, the solution containing biomolecules is not accommodated in a filling chamber from the beginning, and the solution containing biomolecules is accommodated in the filling chamber by sucking through a nozzle having an injection port. In this manner, when a configuration in which a filling operation in the filling chamber is required is used, it is possible to inject any required solution containing biomolecules into the injection target. Therefore, in the injector according to the first aspect of the present invention, a syringe part is removable.
Herenafter, regarding an example of an injector according to one embodiment of the first aspect of the present invention, a syringe 1 (needleless syringe) will be described with reference to the drawings. Here, the configuration of the following embodiment is an example, and the first aspect of the present invention is not limited to the configuration of the embodiment. Here, the terms “distal end side” and “proximal end side” are used as terms that represent the relative positional relationships in the syringe 1 in the longitudinal direction. The “distal end side” represents a position near the tip of the syringe 1 to be described below, that is, near an injection port 31a, and the “proximal end side” represents a side on the side opposite to the “distal end side” of the syringe 1 in the longitudinal direction, that is, a side on the side of a driving unit 7. In addition, this example is an example in which combustion energy of an explosive that is ignited by an ignition device is used as injection energy and a DNA. solution is used as solution containing bioolecules, but the first aspect of the mpresent invention is not limited thereto.
(Configuration of Syringe 1)
As described above, the syringe assembly 10 is configured to be detachable from the housing 2. A filling chamber 32 formed between the syringe part 3 and the plunger 4 included in the syringe assembly 10 is filled with a DNA solution, and the syringe assembly 10 is a unit that is discarded whenever the DNA solution is injected. On the other hand, on the side of the housing 2, a battery 9 that supplies power to an igniter 71 included in the driving unit 7 of the syringe assembly 10 is included. When a user performs an operation of pressing a button 8 provided in the housing 2, supply of power from the battery 9 is performed between an electrode on the side of the housing 2 and an electrode on the side of the driving unit 7 of the syringe assembly 10 via a wiring. Here, the shape and position of both electrodes are designed so that the electrode on the side of the housing 2 and the electrode on the side of the driving unit 7 of the syringe assembly 10 are automatically brought in contact when the syringe assembly 10 is mounted in the housing 2. In addition, the housing 2 is a unit that can be repeatedly used as long as power that can be supplied to the driving unit 7 remains in the battery 9. Here, in the housing 2, when the battery 9 has no power, only the battery 9 may be replaced, and the housing 2 may be continuously used.
In addition, in the syringe main body 6 shown in
(Injection Target)
The injection target in the first aspect of the present invention has no limitation, and may be, for eample, any of cells, cells in cell sheets, cells in tissues, cells in organs (body organs), cells in organ systems, and cells in individuals (living bodies). Examples of a preferable injection target include injection targets derived from mammals. The injection target more preferably cells in mammalian individual (living body), still more preferably cells in the skin, and yet more preferably cells in one or more tissues selected from the group consisting of intradermal, subcutaneous and cutaneous muscles.
Here, when the mammalian individual (living body) has an adipose layer, the subcutaneous muscle includes the adipose layer. For example, swine have a thick adipose layer, whereas rats do not have an adipose layer or if they have an adipose layer, the adipose layer is thin.
In this case, a method in which a solution containing biomolecules is injected from an injector into a skin surface of a mammalian individual (living body), and injected from the skin surface into cells in one or more tissues selected from the group consisting of intradermal, subcutaneous and cutaneous muscles in the skin can be used.
In addition, a system in which a solution containing biomolecules is injected from an injector into an injection target may be any of an in vitro system, an in vivo system, and an ex vivo system.
In addition, the mammal is not particularly limited, and examples thereof include humans, mice, rats, guinea pigs, hamsters, cows, goats, sheep, swine, monkeys, dogs, and cats. In addition, depending on the injection target, a form in which humans are excluded from mammals may be exemplified.
(Method of confirming that solution containing biomolecules is directly injected into cell nucleus of injection target)
A method of confirming that a solution containing biomolecules is directly injected into a cell nucleus of an injection target is not particularly limited, and a known biological technique can be used. For example, a method which biomolecules are fluorescently labeled in advance, injected into a cell nucleus of an injection target, and then observed under fluorescence microscope may be exemplified. In examples to be described below, a Cy3-labeled plasmid V7905 (commercially available from Mirus Bio LLC.) is used as DNA that is directly injected into a cell nucleus of cells in the mammalian individual (living body) and DAPI is used as a nuclear staining dye. For example, a sample can be prepared by acquiring a tissue immediately after injecting DNA and separating it into pieces. In this case, DAPI staining may be performed simultaneously. Red fluorescence is exhibited at a position at which the Cy3-labeled plasmid V7905 is injected, and blue fluorescence is exhibited due to DAPI at a position of the cell nucleus. Therefore, according to observation under a fluorescence microscope, a position at which blue purple fluorescence is exhibited can be identified as a position of the Cy3-labeled plasmid V7905 directly injected into the cell nucleus.
<Second Aspect>
The second aspect of the present invention is a method of injecting a solution containing biomolecules to a cell nucleus of an injection target using the injector of the first aspect.
The description of the first aspect of the present invention above applies to the injector, the injection target, and the solution containing biomolecules in the second aspect of the present invention.
Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples without departing from the spirit and scope of the invention.
(Evaluation of injection speed of injector)
The injector shown in
This example was the same as Example 1-1 except that 15 mg of ZPP was used.
This example was the same as Example 1-1 except that 55 mg of ZPP was used.
This example was the same as Example 1-1 except that 90 mg of ZPP was used.
(Test of injecting DNA solution into cell nucleus of cells in mammalian :individual (living body))
The injector used in Example 1 was filled with 30 μL of a solution containing a Cy3-labeled plasmid V7905 (solvent: endotoxin-free TE buffer, final concentration: 0.1 mg/mL). Regarding the explosive, 35 mg of an explosive containing zirconium and potassium perchlorate (ZPP) was used, and regarding the gas generating agent, 40 mg of a single base smokeless explosive. The solution was injected into the skin of the lumbar back of a female SD rat (10-week old). Here, as described above, no gas generating agent was used in Example 1-1, but the gas generating agent was used in this example. This is because it is considered that use of a gas generating agent does not affect the initial injection speed defined in the present invention.
Immediately after injection, the skin was removed and frozen in an OCT compound (embedding agent for preparing a frozen tissue section (Tissue Tech. O.C.T. Compound), commercially available from Sakura Finetek Japan Co., Ltd.) with dry ice. Using a cryostat (commercially available from Leica), the cross section of the injection part was cut into slices with a thickness of 6 μm and encapsulated with an encapsulant containing DAPI. The fluorescence of the prepared sample was observed under an all-in-one fluorescence microscope (Z-X700, commercially available from Keyence Corporation), and a red fluorescence image of Cy3 and a blue fluorescence image of DAPI were obtained with a thickness of 0.1 to 0.4 μm. In order to obtain an injection distribution in the injection area, images in a plurality of fields were obtained. The results are shown in
A proportion of the number of cells into which DNA was directly injected was calculated as follows using a hybrid cell count function. That is, for cells in each analysis target area (each area surrounded by a white frame in
This example was the same as Example 2-1 except that 15 mg of ZPP was used. The results are shown in
In
This example was the same as Example 2-1 except that 55 mg of ZPP was used, and female swine (15-week old, edible Sangenton (LWD) (hybrid of Landrace species, Yorkshire species, and Duroc species)) were used in place of the female SD rat (10-week old), and injection into the skin of the abdomen was performed.
Here, when a proportion of the number of cells into which DNA was directly injected was calculated, as analysis target areas, an area (a1) surrounded. by a white dashed frame on the upper side and an area (b1) surrounded by a white dashed frame on the lower side in
As shown in
The same applies to the image (b2) shown in
This example was the same as Example 2-3 except that 90 mg of ZPP was used. The results are shown in
In
1: Syringe, 2: Housing, 3: Syringe part, 4: Plunger, 5: Piston, 6: Syringe main body, 7: Driving unit, 8: Button, 9: Battery, 10: Syringe assembly, 31: Nozzle unit, 31a: Injection port, 32: Filling chamber, 71: Igniter
| Number | Date | Country | Kind |
|---|---|---|---|
| 2018-021910 | Feb 2018 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2019/004724 | 2/8/2019 | WO | 00 |
