Composition comprising fibrous acellular dermal matrix by drying and method for producing the same

Abstract

To provide a composition comprising a fibrous acellular dermal matrix having enhanced physical properties, which is easily applicable even to a bent wound site, and a method for producing the same.SOLUTION: A composition comprising 48 to 95.5 wt.% of a fibrous acellular dermal matrix and 0.5 to 52 wt.% of water, wherein a biocompatible polymer is not added, an average tensile strength value of 0.2 N / mm2 or more is satisfied, and the composition is a sheet type.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a composition containing a fibrotic acellular dermal matrix and a method for producing the same, and to a composition containing a fibrotic acellular dermal matrix to which a drying method is applied and a method for producing the same.

Background Art

[0002] A wound refers to a state in which the skin or other tissues are cut or damaged by external pressure, breaking the tissue continuity, and usually damaging the dermis layer of the skin and opening the skin. Wound surgery basically prevents infection and suppresses the inflammatory reaction by suturing and bandaging the wound site to block exposure to the external environment. The materials of wound dressings can be broadly divided into autologous dermis and allogeneic dermis, and wound dressings can be manufactured by a method of extracting specific polymers from the materials and a method using a dermal matrix.

[0003] An acellular dermal matrix (ADM) is obtained by removing the epidermis from a cadaveric skin tissue donated to eliminate the immune rejection reaction and then removing the cells in the dermis. It is widely used in this field for soft tissue reconstruction surgery and is also widely used for allograft for burn treatment. The dermal tissue is composed of 80 - 90% collagen, elastin, and glycosaminoglycan.

[0004] On the one hand, in 1994, LifeCell commercialized an acellular dermal matrix (ADM) produced by decellularizing and lyophilizing skin tissue collected from cadavers (Alloderm (allograft)), which was used for burn treatment, skin reconstruction, etc. Alloderm (allograft) was safer than xenogeneic products and showed excellent engraftment rates and healing effects. Similar products such as AlloMax from Bard Dabol and FlexHD from Ethicon were developed. However, products like the above had problems with reduced flexibility and were difficult to use on wound sites that were bent or deeply dug.

[0005] To solve such problems, in 1999, LifeCell developed a technology to granulate the acellular dermal matrix and launched the AlloDerm (Cymetra) product in the form of an injectable micronized preparation. Additionally, Wright Medical Group developed the Graftjacket product in an injectable form and launched the Graftjacket Xpress product. In 2014, L&C Bio developed a composition in which hyaluronic acid was cross-linked after granulating the acellular dermal matrix. However, in the case of a composition in which acellular dermal matrix particles and a biocompatible polymer are cross-linked as described above, although the structural stability is high, the degree of cross-linking, viscoelasticity, hardness, and extrusion force also increase. While it is suitable for applications such as fillers and shape-retaining materials, it still lacks in terms of application as a wound dressing material. In the case of the micronized form, there was a problem that it could not be fixed to the wound site in a liquid form and would flow out of the dressing and could not be evenly distributed over the wound.

[0006] Therefore, there is an urgent need to develop a form of acellular dermal matrix that can be fixed to the wound site.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] The object of the present invention was derived to solve the above problems. By not applying a biocompatible polymer and applying a step of drying with a mold, a composition containing a fibrotic acellular dermal matrix by drying, which is easy to apply to a bent wound site and has enhanced physical properties, and a method for producing the same are provided.

Means for Solving the Problems

[0009] To achieve the above object, a composition containing a fibrotic acellular dermal matrix by drying according to an embodiment of the present invention contains 48 to 95.5% by weight of a fibrotic acellular dermal matrix and 0.5 to 52% by weight of water, and no biocompatible polymer is added.

[0010] A method for producing a composition containing a fibrotic acellular dermal matrix by drying according to another embodiment of the present invention includes: (a) a step of pulverizing an acellular dermal matrix to produce a fibrotic acellular dermal matrix; (b) a step of adding water to the fibrotic acellular dermal matrix to rehydrate it; and (c) a step of drying the rehydrated fibrotic acellular dermal matrix.

Effects of the Invention

[0011] According to an embodiment of the present invention, a composition containing a fibrotic acellular dermal matrix by drying and a method for producing the same do not have a biocompatible polymer added, do not have a physical property change due to heat, and do not require a step for heat-treating the biocompatible polymer, so the manufacturing process can be simplified and the manufacturing cost can be reduced.

[0012] In addition, since it has a structure very similar to the dermal matrix of a human body wound site, it has excellent biocompatibility and in-vivo preservation properties, maintains a good wet environment, has an excellent therapeutic effect, and may be easy to apply to a bent wound site.

[0013] Also, by performing the step of drying with a mold, the physical properties and tensile strength are improved, and it may be easier for the operator to use during the procedure.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

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Figure 4

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Figure 6

Modes for Carrying Out the Invention

[0015] Hereinafter, the present invention will be described in detail according to the embodiments of the present invention with reference to the accompanying drawings. However, the following embodiments are presented as examples of the present invention, and when it is determined that a detailed description of well-known famous techniques or configurations to those skilled in the art will unnecessarily obscure the gist of the present invention, the detailed description can be omitted, and thus the present invention is not limited. The present invention can be variously modified and applied within the scope of the claims described below and the equivalent categories interpreted therefrom.

[0016] In addition, the terminology used in this specification is the terminology used to appropriately represent the preferred embodiments of the present invention, which may vary according to the intentions of users and operators or the conventions in the field to which the present invention belongs. Therefore, the definitions of this terminology should be based on the content throughout this specification. Throughout the specification, when a certain part refers to a certain component as "including", this means that, unless otherwise stated, it does not exclude other components, but may further include other components.

[0017] Throughout this specification, the "%" used to indicate the concentration of a specific substance is, unless otherwise specified, %(w / w) for solid / solid, %(w / v) for solid / liquid, and %(v / v) for liquid / liquid.

[0018] Hereinafter, a composition containing a fibrotic acellular dermal matrix according to an embodiment of the present invention will be described in detail.

[0019] The composition containing the fibrotic acellular dermal matrix of this embodiment contains a fibrotic acellular dermal matrix and water.

[0020] The fibrotic acellular dermal matrix (ADM) has excellent biocompatibility with high cell adhesion ability and low immune response compared to conventional animal-derived products, and is a component widely used for the reconstruction, regeneration, and strengthening of skin, muscle, and ligaments in plastic and orthopedic surgery. The fibrotic acellular dermal matrix used in this embodiment can contain 90% or more, more preferably 50 - 90%, of those with a major axis length of 10 - 3,000 μm, preferably 100 - 2,000 μm. However, if a large number of those less than 100 μm are included, when attempting to process into a sheet type, the form may not be correctly made, or it may only be made into a film form and it may be difficult to adhere flexibly to the wound site. Such a fibrotic acellular dermal matrix can be included at 48 - 95.5% by weight.

[0021] Water is an ingredient added for rehydration and can be contained in an amount of 0.5 to 52% by weight. If the water content is less than 0.5% by weight, it may be difficult to hydrate the acellular dermal matrix. If it exceeds 52% by weight, it may be difficult to achieve the desired formulation due to excessive use.

[0022] In this embodiment, no biocompatible polymer is added. Since there is no physical property change due to heat and no step for heat-treating the biocompatible polymer is required, simplification of the manufacturing process and reduction of manufacturing costs can be achieved. Also, because it has a structure very similar to the dermal matrix of the wound site of the human body, it has excellent biocompatibility and in-vivo preservation properties, maintains a good wet environment, has excellent therapeutic effects, and may be easy to apply to a bent wound site.

[0023] In this embodiment, the fibrous acellular dermal matrix can mean that the individual particulate forms of the acellular dermal matrix are in an elongated fibrous form like a thread rather than a spherical or streamline shape.

[0024] In this embodiment, it can further contain stem cells, growth factors, or a mixture thereof.

[0025] Also, in this embodiment, it can further contain one or more selected from pharmaceutically used antibacterial agents, excipients, and additives.

[0026] As the antibacterial agent, one or more selected from short-chain alcohols, benzoalkonium chloride (BAC), didecyl dimethyl ammonium chloride (DDAC), zeolite (CWT-A), isothiazolone, alkyldimethylammonium chloride, triazine, 2-thiocyanomethylthiobenzothiazole, methylene bisthiocyanate, acrolein, dodecylguanidine hydrochloride, chlorophenol, quaternary ammonium salts, glutaraldehyde, dithiocarbamate, 2-mercaptobenzothiazole, para-chloro-meta-xylenol, silver, chlorhexidine, polyhexamethylene biguanide, n-halamine, triclosan, phospholipids, α-hydroxy acids, 2,2-dibromo-3-nitrilopropionamide, 2-bromo-2-nitro-1,3-propanediol, panthenol, iodine, bromine, hydrogen peroxide, chlorine dioxide, vegetable oils, plant extracts, benzoalkonium chloride, chlorine and sodium hypochlorite can be used.

[0027] As the excipient, one or more selected from stabilizers, antioxidants, osmotic pressure regulators, buffers and pH regulators can be used. Specifically, one or more selected from starch, cellulose, glucose, lactose, sucrose, gelatin, corn, rice, wheat flour, chalk, silica gel, magnesium stearate, sodium stearate, glycerol monostearate, sodium chloride, glycerol, propylene glycol, water and ethanol can be used.

[0028] As the additive, one or more selected from physiologically biocompatible buffers (tris hydrochloride), chelating agents (DTPA or DTPA-bisamide), and calcium chelate complexes (calcium DTPA, CaNaDTPA-bisamide) can be used. In some cases, calcium or sodium salts (calcium chloride, calcium ascorbate, calcium gluconate or calcium lactate) can be used.

[0029] The composition can further contain one or more of stem cells and growth factors.

[0030] In this embodiment, the composition containing the fibrotic acellular dermal matrix can be produced in the form of an aqueous solution, a suspension, an emulsion, a paste, a cream, a balm, an ointment, a foam, a sheet, a gel, a gum, a spray, a slurry, a film, granules, a patch, a powder, etc. Preferably, it may be of a sheet type and can be used as a coating material, an adhesive, a surgical and medical device, artificial skin, a bandage, a foaming agent, an anti-adsorption agent, or a graft material.

[0031] Hereinafter, a method for producing a composition containing a fibrotic acellular dermal matrix according to another embodiment of the present invention will be described in detail with reference to the drawings.

[0032] FIG. 1 is a process diagram for explaining a method for producing a composition containing a fibrotic acellular dermal matrix according to another embodiment of the present invention.

[0033] Referring to FIG. 1, first, an acellular dermal matrix is pulverized to produce a fibrotic acellular dermal matrix (S10).

[0034] The acellular dermal matrix can be ground with one or more grinders selected from a cutting mill, a food processor, an agate grinder, a cryogenic grinder, a micronizer, a vibratory micro mill, a jaw crusher, a mortar grinder, a planetary mill, a disk mill, a ball mill, a knife mill, and a variable speed rotor mill to produce a fibrous acellular dermal matrix. At this time, it is preferable to set the rotation speed of the grinder to 500 to 2000 rpm so that grinding can be facilitated in a short time.

[0035] On the other hand, in the present embodiment, as the acellular dermal matrix, a step of preparing a human-derived skin tissue that has not undergone a separate epidermis removal and defatting process, a step of treating the skin tissue with a hypotonic solution containing a surfactant, and a step of washing the treated skin tissue with an isotonic solution can be used. Here, as the acellular dermal matrix, it is preferable to apply one that satisfies a thickness of 0.1 mm to 3 mm.

[0036] Next, water is added to the fibrous acellular dermal matrix for rehydration (S20).

[0037] Water can be added in an amount of 300 to 2000 parts by weight to 100 parts by weight of the acellular dermal matrix produced in step S10 for hydration. If the water content is less than 300 parts by weight, it becomes difficult to hydrate the fibrous acellular dermal matrix, and if it exceeds 2000 parts by weight, the heat drying time described later may become longer due to unnecessary use, which is not preferable. In the present embodiment, the water can be sterilized distilled water.

[0038] Then, the rehydrated fibrous acellular dermal matrix is heat-dried (S30).

[0039] The fibrotic acellular dermal matrix rehydrated in step S20 can be heat-dried at 30 to 50 °C for 6 hours or more, for example 10 hours or more, for example 10 to 24 hours, preferably 16 to 18 hours, until the water content becomes 0.5 to 52% by weight in a mold, preferably a grid-shaped mold. If the temperature is less than 30 °C, it may take an excessive amount of time for drying. If it exceeds 50 °C, not only can the human tissue be deformed and the amino acid content be reduced, but also the tensile strength and the degree of hydration can be reduced.

[0040] Under the above heat drying conditions, the average value of the tensile strength of the fibrotic acellular dermal matrix is 0.2 N / mm 2 By satisfying the above, in some cases, it may be easier for the operator to use during the operation than before.

[0041] After step S30, the step of processing the heat-dried fibrotic acellular dermal matrix into a sheet type can further be included.

[0042] After applying the fibrotic acellular dermal matrix heat-dried in step S30 to a mold (mold or frame), it can be shaped and processed into a sheet type, and it goes without saying that it can be manufactured in various ways according to the horizontal, vertical, and thickness sizes required by the wound site or surgical characteristics.

[0043] On the other hand, before processing into a sheet type, non-chemical crosslinking using radiation, reduced pressure, and heat or a chemical crosslinking step using a crosslinking agent can further be carried out according to physical properties (such as the degree of crosslinking and the degree of curing).

[0044] Hereinafter, the present invention will be described in more detail using examples. These examples are merely for explaining the present invention more specifically, and it is self-evident to those having ordinary knowledge in the technical field that the scope of the present invention is not limited thereby.

[0045] Production Example 1. Production of Acellular Dermal Matrix The EURO skin bank purchased skin tissue from Allosource and CTS, selected tissues with a thickness of 0.5 mm or more, removed the adipose tissue adhering to the skin tissue using forceps, and then washed it three times with a sterile number. Next, it was immersed in a hypotonic solution (Tris-Hcl, EDTA, NaOH, and SDS) and treated for 6 hours. Then, the skin tissue was washed with PBS at 4°C overnight to remove the remaining fat, epidermis, cells, and hypotonic solution on the skin tissue, and then washed with an isotonic solution (Tris-HCl, EDTA, NaCl, NaOH) for 6 hours to produce a decellularized human-derived acellular dermal matrix.

[0046] Example 1. Preparation of a composition containing a fibrotic acellular dermal matrix The human-derived acellular dermal matrix produced in Production Example 1 was pulverized and fibrotic using a cutting mill to produce a fibrotic acellular dermal matrix. Here, 10 times the sterile distilled water was added for rehydration, placed in a grid-shaped mold, heat-dried at 30°C to 50°C for 6 hours or more, then applied to the mold to take shape and processed into a sheet type to produce a composition containing a fibrotic acellular dermal matrix.

[0047] On the other hand, for the composition containing the fibrotic acellular dermal matrix according to Example 1, the weights before and after heat-drying treatment at a high temperature of 126°C for 10 minutes or more are shown in Figure 2.

[0048] Looking at Figure 2(c), it can be confirmed that the composition containing the fibrotic acellular dermal matrix contains 48.32% by weight of the fibrotic acellular dermal matrix and 51.68% by weight of water, based on the pre-drying weight of 0.387 g shown in Figure 2(a) and the post-drying weight of 0.187 g shown in Figure 2(b).

[0049] ※ In Example 1, drying did not progress during overnight at RT which is a temperature less than 30°C.

[0050] Comparative Example 1. Preparation of a composition containing a fibrotic acellular dermal matrix It was produced in the same manner as in Example 1, except that the heat treatment was carried out at 60°C for 6 hours or more.

[0051] Comparative Example 2. Production of a Composition Containing Fibrous Acellular Dermal Matrix It was produced in the same manner as in Example 1, except that the heat treatment was carried out at 70 °C for 6 hours or more.

[0052] Comparative Example 3. Production of a Composition Containing Fibrous Acellular Dermal Matrix It was produced in the same manner as in Example 1, except that the heat treatment was carried out at 100 °C for 6 hours or more.

[0053] Experimental Example 1. Appearance Evaluation The appearances of the compositions containing the fibrous acellular dermal matrix prepared in Example 1 and Comparative Examples 1 to 3 were visually confirmed and evaluated.

[0054] As a result, as shown in Figure 3, it was confirmed that Example 1 had a structure very similar to the dermal matrix of the wound site of the human body in appearance, there were somewhat differences in appearance between Comparative Examples 1 and 2 and the dermal matrix of the wound site of the human body, and it was confirmed that the tissue was burned in Comparative Example 3.

[0055] Thus, the composition containing the fibrous acellular dermal matrix of the present invention does not need to be heated to a high temperature because no biocompatible polymer is added, there is no physical property change due to heat, and no step for heat-treating the biocompatible polymer is required, so it can be confirmed that the manufacturing process can be simplified and the manufacturing cost can be reduced.

[0056] Experimental Example 2. Evaluation of Amino Acid Content Depending on Heat Treatment Temperature To confirm the change in amino acid content depending on the heat treatment temperature, the amino acid contents of Example 1, Comparative Examples 1 and 2 were measured using an amino acid automatic analyzer (S433D, Sykam GmbH Co., Germany), and the results are shown in Figure 4.

[0057] Referring to Figure 4, it can be confirmed that the amino acid content decreases from Example 1 to Comparative Examples 1 and 2, and this was presumably because human tissue deformation occurred in Comparative Examples 1 and 2.

[0058] The composition containing the fibrotic acellular dermal matrix produced according to the embodiment of the present invention has a structure very similar to the dermal matrix at the wound site of the human body. Therefore, it has excellent biocompatibility and in-vivo preservation property, and it can be seen that the therapeutic effect is improved and it is easy to apply to a bent wound site.

[0059] Experimental Example 3. Evaluation of water content by heat treatment temperature In order to confirm the water content by heat treatment temperature, Examples 1, Comparative Examples 1 and 2 were put into a tube filled with water and observed, and the results are shown in FIG. 5.

[0060] Referring to FIG. 5, it can be confirmed that Example 1 sank within several seconds, while Comparative Examples 1 and 2 continuously floated without sinking. This was presumably due to the influence of drying and shrinkage at high temperature.

[0061] It can be seen that the composition containing the fibrotic acellular dermal matrix produced according to the embodiment of the present invention maintains a good wet environment, has an excellent therapeutic effect, and is easy to apply to a bent wound site.

[0062] Experimental Example 4. Evaluation of tensile strength by heat treatment temperature In order to confirm the tensile strength by heat treatment temperature, the results are shown in FIG. 6.

[0063] Referring to FIG. 6, it was confirmed that the tensile strength of Comparative Examples 1 and 2 decreased compared to Example 1.

[0064] It can be seen that the composition containing the fibrotic acellular dermal matrix produced according to the embodiment of the present invention does not need to be heated at high temperature because no biocompatible polymer is added, and there is no physical property change due to heat. By performing the step of heat drying, especially heat drying with a mold, the physical properties and tensile strength are improved, and it is easy for the operator to use during the operation.

[0065] As described above in detail with respect to exemplary embodiments of the present invention, the scope of the rights of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention defined in the following claims also belong to the scope of the rights of the present invention.

[0066] All technical terms used in the present invention are used in the meaning generally understood by ordinary skilled persons in the relevant field of the present invention, unless otherwise defined. The content of all publications described as references in this specification is incorporated into the present invention.

Claims

1. A composition comprising 48 to 95.5% by weight of a fibrotic acellular dermal matrix and 0.5 to 52% by weight of water, and containing no added biocompatible polymer, the composition comprising a fibrotic acellular dermal matrix.

2.

3. The average tensile strength is 0.2 N / mm ２ The composition containing the acellular dermal matrix without fibrosis according to claim 1, which satisfies the above.

4. The composition according to claim 1, further comprising stem cells, growth factors, or a mixture thereof, the composition comprising a fibrotic acellular dermal matrix.

5. The composition according to claim 1, wherein the composition is in sheet form, the composition comprising a fibrotic acellular dermal matrix.

6. A method for producing a composition comprising a fibrotic acellular dermal matrix, the method comprising: (a) pulverizing an acellular dermal matrix to produce a fibrotic acellular dermal matrix; (b) adding water to the fibrotic acellular dermal matrix to rehydrate it; and (c) heat-drying the rehydrated fibrotic acellular dermal matrix.

7. The method for producing a composition comprising a fibrotic acellular dermal matrix according to claim 5, wherein the heat-drying in step (c) is carried out at 30 to 50°C for 6 hours or more.

8.

9.

10. The method for producing a composition comprising a fibrotic acellular dermal matrix according to claim 5, wherein the heat-drying in step (c) is carried out in a mold.

11. The method for producing a composition comprising a fibrotic acellular dermal matrix according to claim 5, further comprising, after step (c), (d) processing the heat-dried fibrotic acellular dermal matrix into a sheet form.

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