KR20170048432A

KR20170048432A - Bone graft material coated with osteogenic protein and extracellular matrix and method for manufacturing the same

Info

Publication number: KR20170048432A
Application number: KR1020177007986A
Authority: KR
Inventors: 정홍희; 이정수; 이광일; 김영식; 장주웅; 심영복
Original assignee: 주식회사 셀루메드
Priority date: 2014-08-25
Filing date: 2015-08-25
Publication date: 2017-05-08
Also published as: WO2016032197A1; KR101962251B1

Abstract

The present invention relates to a bone graft material and a method for manufacturing the same, and more particularly, to a bone graft material coated with an extracellular matrix to which an osteogenic protein is added, and a method for producing the bone graft material.

Description

Bone graft material coated with osteogenic protein and extracellular matrix and method for manufacturing the same

Numerous experimental and clinical attempts have been made for the rapid and complete recovery of defective bone, and a variety of bone grafts, bone substitutes and bone growth factors have been studied and developed in the course of their efforts. However, an ideal and perfect bone substitute has not yet been developed, and various studies are being conducted to find it.

The autologous bone graft, which is the most ideal method for bone defect, requires additional surgery on other parts of the body, and the quality of the bone taken and the amount of bone to be harvested are limited according to the pathological condition of the harvesting site. To overcome the drawbacks of autogenous bone grafting, graft materials for treating bone defects using genetically heterogeneous bone have been developed. However, in the case of heterogeneous bone, the protein is deproteinized in order to minimize cellular antigenic substances.

On the other hand, bone graft materials are often used to increase the natural regeneration process when defects or wounds are present in the bone. Studies have been carried out to attach materials capable of improving tissue regeneration in order to improve the bone regeneration efficiency of bone graft materials have.

These substances can help to induce and differentiate osteocytes, and can be BMP (Bone Morphogenic Protein), PDGF (Platelet Derived Growth Factor), VEGF (Vascular Endothelial Growth Factor), and the like. Among them, BMP-2 is known to play a most important role in the regeneration of bone tissue, and various studies on its use have been made.

However, currently, factors such as BMP-2 remain stable, and bone graft materials are not yet developed. When bone grafts are transplanted into bone defect sites, BMP-2 is often not sufficiently conjugated to allow stable efficacy during treatment.

Usually, BMP-2 has been used as a method of injecting bone defects by mixing with saline. However, even if BMP-2 is injected by this method, the effect is maintained for several hours to several days, and most of it is decomposed. Considering that it takes several to several months to recover bone defect, BMP-2 There is a problem in that the effect by the light emitting diode can not be sustained and is insignificant. In addition, a large amount of BMP-2 should be applied to maintain the effect, but this is a problem of high cost.

Under these technical backgrounds, the inventors of the present application found that, in the case of a bone graft coated with an extracellular matrix to which an osteogenic protein is added, the osteogenic protein can be continuously maintained during bone defect treatment, And completed the present invention.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a bone graft material capable of solving the problems of the prior art and exhibiting excellent bone forming ability suitable for bone defect treatment and a method for manufacturing the same.

The present invention relates to a method for preparing bone graft coated with an extracellular matrix (ECM) to which an osteogenic protein (BMP) is added, comprising the steps of:

(a) mixing a bone graft material with an osteogenic protein / extracellular matrix hydrogel;

(b) lyophilizing the mixture of step (a); And

(c) pulverizing the lyophilizate of step (b) and separating the bone graft material coated with the osteogenic protein / extracellular matrix hydrogel by a micro sieve.

The present invention also relates to a bone graft coated with an extracellular matrix (ECM) to which a bone morphogenetic protein (BMP) is added, which is produced by the above production method.

1 shows a scanning electron microscope (SEM) image of a bone graft material coated with an extracellular matrix (ECM) to which bone morphogenetic protein (BMP) has been added.
FIG. 2 shows the cell proliferation results of Rat-derived Mesenchymal stem cells cultured in bone graft coated with extracellular matrix (ECM) supplemented with bone morphogenetic protein (BMP).
FIG. 3 shows the expression of Alkaline Phosphatase of Mesenchymal stem cells derived from Rat cultured in bone graft coated with extracellular matrix (ECM) supplemented with bone morphogenetic protein (BMP).
FIG. 4 shows the result of Alkaline Phosphatase staining of mesenchymal stem cells derived from Rat cultured in bone graft coated with extracellular matrix (ECM) containing bone morphogenetic protein (BMP).
Figure 5 shows the results of analysis of the amount of BMP2 released from DBM powder coated with ECM / BMP2.

DETAILED DESCRIPTION OF THE INVENTION AND PREFERRED EMBODIMENTS

In one aspect, the present invention relates to a method for preparing a bone graft material coated with an osteogenic protein (BMP) -adrenergic extracellular matrix (ECM) comprising the steps of: (a) Mixing the outer substrate hydrogel; (b) lyophilizing the mixture of step (a); And (c) pulverizing the lyophilizate of step (b) and separating the bone graft material coated with the osteogenic protein / extracellular matrix hydrogel with a micro sieve.

The manufacturing method according to the present invention comprises (a) mixing a bone graft material and an osteogenic protein / extracellular matrix hydrogel. The mixing can be carried out, for example, through a bone-forming protein / extracellular matrix hydrogel with a bone graft material through a mixing device, for example, a paste mixer.

The bone graft material may be homologous or xenograftable, for example, a demineralized bone matrix in connection with the reconstruction of a defective bone, which is safe from the risk of transmission of disease from the donor site.

The extracellular matrix is a component other than the cells in the tissue. The extracellular matrix possesses various growth factors and cytokines secreted by the cells and can play an important role in determining the functions of the cells. Cells can best be adapted to extracellular matrix environments similar to their own, and can be used as scaffolds because their physiological activity is most active.

The extracellular matrix may be in the form of a gel, for example, as a mixture of soluble and insoluble material separated from acid-treated demineralized bone. The extracellular matrix may contain high amounts of growth factors, non-collagenous proteins and type I collagen. An extracellular matrix according to the present invention can be prepared, for example, by including the following steps:

a) preparing a demineralized bone matrix solution by adding a citric acid solvent at a concentration of 3M to 5M to the demineralized bone matrix; b) separating the solution containing the soluble material of the demineralized bone matrix from the demineralized bone matrix solution and the insoluble material; c) neutralizing the solution comprising the soluble material; d) drying the result of step c); e) rehydrating the result of step d); And f) repeating the step of freezing the solution re-hydrated in step e) at a temperature of -80 ° C to -60 ° C and thawing it.

Such an extracellular matrix and a method for its production are disclosed in Korean Patent No. 1329559 of the present applicant and incorporated herein by reference.

The osteogenic protein may be, for example, BMP-2, BMP-4, BMP-7 or BMP-14, preferably BMP-2.

The osteogenic protein / extracellular matrix hydrogel according to the present invention may be one in which a solution containing a soluble substance in the extracellular matrix acts as a gel carrier to be in the form of a hydrogel, to which an osteogenic protein is added.

In one embodiment, the bone-derived extracellular matrix can be included, for example, at a concentration of 1 to 20%, preferably 1 to 10%. In the case of including the bone-derived extracellular matrix in the above-mentioned range, the bone graft material produced through the bone graft material composition according to the present invention can continuously maintain the bone formation protein exhibiting the bone loss restoration effect during the treatment. When the concentration of bone-derived extracellular matrix is out of the above-mentioned range, it is not prepared in the form of hydrogel due to the concentration of extracellular matrix, and thus there is a problem in coating with bone graft material.

The bone-derived extracellular matrix to which the bone-forming protein is added and the bone graft material may be contained in a weight ratio of 0.1-10: 1, preferably 0.5-5: 1, more preferably 0.5-1.5: 1. When the bone graft material is contained in the ratio described above, the bone graft material prepared through the bone graft material composition according to the present invention may be a form in which the osteogenic extracellular matrix is uniformly coated. When the weight ratio of the osteogenic extracellular matrix to the bone graft material to which the osteogenic protein is added is out of the above range, there is a problem that the osteoconductive material is not uniformly coated.

The osteogenic protein may be added at a concentration of, for example, 1-20 占 퐂 / ml, preferably 1-15 占 퐂 / ml, more preferably 1-10 占 퐂 / ml. According to the present invention, osteogenic proteins are immobilized through bone-derived extracellular matrix, so that even when the osteogenic protein in saline is directly injected into the bone defect site together with the graft material, Formation-inducing effect can be achieved.

The process according to the present invention comprises (b) lyophilizing the mixture of step (a). The mixture prepared in step (a) may be lyophilized at -120 캜 to -50 캜 for 24 to 72 hours. It has an effect of partially removing microorganisms in water that can be present in the graft material through freeze-drying, and has an effect of inhibiting the propagation of microorganisms that may be caused by moisture. Preferably the moisture content can be up to 6%.

The method according to the present invention comprises (c) pulverizing the lyophilisate of step (b) and separating the bone graft material coated with the osteogenic protein / extracellular matrix hydrogel with a micro sieve. The lyophilizate of step (b) may be pulverized and dispersed, for example, with a mortar or a mixer, and then the pulverized dispersion is passed through a microsieve to obtain a powdery osteogenic protein / extracellular matrix The hydrogel-coated bone graft material can be separated.

At this time, the microsieve has a sieve size for separating into a form suitable for producing a bone graft material, and may have a sieve size of, for example, 0.5 to 900 μm, preferably 200 to 300 μm.

In another aspect, the present invention is a bone graft material produced by the above-described method, wherein the graft material is coated with an extracellular matrix (ECM) to which an osteogenic protein (BMP) is added. The bone graft material according to the present invention can exhibit safe and improved bone forming ability.

The bone graft material according to the present invention may be, for example, in the form of a powder, and the size (particle size) of the powder may be, for example, 500 탆 to 900 탆, preferably 200 탆 to 300 탆.

The description of the above-described bone formation proteins and bone-derived extracellular matrix and bone graft materials can be equally applied to bone graft materials according to the present invention.

Hereinafter, the present invention will be described in more detail with reference to Examples. It is to be understood by those skilled in the art that these examples are for illustrative purposes only and that the scope of the present invention is not construed as being limited by these examples.

Example 1: Preparation of ECM / BMP-2 coated DBM

1. Manufacture of ECM

(1) Preparation of demineralized bone matrix

The bovine cortical bone (processed by Seloom) was treated with 83% ethanol and 6% hydrogen peroxide solution to remove bone marrow and lipid. Then, the bone was cut into blocks using a band saw machine. The cut block was placed in a bone mill 1 (M20, Fritsch, Germany) and subjected to primary pulverization. Then, the primary pulverized material was placed in a bone mill 2 (M35, IKA, Germany) The size of the water was further reduced. In order to remove debris from the pulverized bone powder, 15 ml of purified water per 1 g of bone powder was added to the vessel, which was then washed for 10 minutes, and the purified water was exchanged for a total of three washes. The washed bone powder was added to a stirrer, 15 ml of 0.6 N HCl was added per 1 g of bone powder, and the mixture was stirred at a rate of 200 rpm for 6 hours at 24 ° C. After the agitation, the washing operation was repeated until the pH of the solution containing the bone powder became 6.0 or more. Thereafter, the bone powder was treated with 83% ethanol and 6% hydrogen peroxide, disinfected, and the supernatant was removed and then stored at -70 ° C for 12 hours. The resultant was lyophilized to prepare a demineralized bone matrix.

(2) Manufacturing of ECM

1.5 kg of demineralized bone matrix prepared in (1) was added to 15 L of 3M citric acid and treated at 100 rpm and room temperature for 72 hours. Using a sieve having a pore size of 20um or more and 50um or less, the soluble material and the insoluble material were separated and a solution containing the soluble material was collected in a 50L tank, and the insoluble material was placed in a 20L tank. 15 L of purified water was added to a 20 L tank containing insoluble matter and washed at 100 rpm. The purified water was changed twice to wash until the pH reached between 7.0 and 7.5. The washed insoluble material was dried at -70 ° C or lower for 12 hours or more using a freeze dryer. A solution containing the soluble material transferred to the 50 L tank was concentrated and refined to 5 L by circulating approximately 45 L of purified water until the pH was between 7.0 and 7.5 using a micro hollow fiber (PALL, USA, 10K cut off) . The solution containing the concentrated soluble substance was dried in a freeze dryer at -70 DEG C or lower for 12 hours or more. The dried soluble material was added to purified water to make an 8% aqueous solution. 8% aqueous solution was frozen at -70 ° C for 3 hours and thawed at room temperature for 12 times. The dried insoluble materials were mixed in a volume ratio of 1: 1 to an aqueous 8% solution which was viscous during the freezing-thawing process, and then filled in a syringe.

2. Preparation of BMP-2 added ECM

BMP-2 (Cellumed) was added at a concentration of 10 ug / ml after 1%, 5%, and 10% ECM hydrogel preparation, and stored at 4 until immediately before use.

3. Preparation of ECM / BMP-2 coated DBM

Bovine DBM (Intergraft) and 1%, 5%, and 10% ECM / BMP-2 hydrogels manufactured by Cellumed SOP regulations were mixed with a paste mixer (Condotech, PDM-300V) : 1 (v / v). The mixture was lyophilized at -70 for 72 hours. After the lyophilized Intergraft / ECM / BMP was in a lump state, it was dispersed in a mortar or a mixer, and the microsieve (CISA) / ECM / BMP. The prepared Intergraft / ECM / BMP was packaged in glass vials, sterilized by gamma sterilization and stored in refrigeration (4).

Test Example 1: Surface analysis of Intergraft / ECM / BMP

The Intergraft / ECM / BMP sample prepared in Example 1 was fixed to a metal plate using a carbon tape, platinum coated with argon for 2 minutes using a plasma sputterer, and then observed under a scanning electron microscope for morphological characteristics. The results are shown in Fig. It was confirmed that ECM / BMP was partially coated on the intergraft surface when ECM concentration was 1 ~ 5%, whereas it was uniformly coated on the intergraft surface when ECM concentration was 10%.

Test Example 2: Evaluation of cell proliferation of Intergraft / ECM / BMP

Rat (Sprague dawley rat / male / 250 ~ 300g)) were inoculated to a 24-well plate at 2 × 10 ⁵ cells. Then, 25 mg of ECM / BMP-coated intergraft coated with 1-10% of ECM / BMP according to Example 1 was cultured for 1, 3, and 7 days, treated with CCK-8 for 3 hours, and OD was measured at 450 nm wavelength Respectively.

The results are shown in Fig. As shown in FIG. 2, the number of proliferating cells increased over time during the incubation period of 1, 3, and 7 days after the evaluation of cell proliferation for each graft material. Compared with each group, 10% of ECM / BMP coated intergrafts were increased on the 1st, 3rd and 7th days compared to the other groups.

Test Example 3: Analysis of bone formation ability of Intergraft / ECM / BMP

1. ALP (Alkaline Phosphatase) activity assay

Mesenchymal stem cells isolated from Rat (Sprague dawley rat / male / 250 ~ 300g) were inoculated 5 × 10 ⁴ into 12 well plates. After that, 25 mg of ECM / BMP-coated intergraft according to Example 1 was added to each well. Ascorbic acid (50 μg / ml), β-Glycrol phosphate (10 mM) And cultured in Dexamethasone (100 mM / ml) for 7 or 14 days. ALP activity was measured using an alkaline phosphatase activity colorimetric assay kit (BioVision) using p-nitrophenylphosphate as a substrate.

The results are shown in Fig. As shown in FIG. 3, the ALP activity as an index of osteogenic differentiation was increased in the 5% and 10% ECM / BMP coated intergrafts compared to the other groups.

2. ALP staining

Mesenchymal stem cells derived from a 12-well plate (Sprague dawley rat / male / 250-300 g) containing 1% to 10% ECM / BMP coated Intergraft according to Example 1 were cultured for 14 days and stained with alkaline phosphate solution Blue stained cells were regarded as osteoblasts.

The results are shown in Fig. According to FIG. 4, osteoblast differentiation was observed in the intergraft coated with ECM / BMP by ALP staining 14 days later, and the osteoblast differentiation was observed in the 10% ECM / BMP coated intergraft.

Example 2 Analysis of Water Absorption Rate of ECM / BMP2 Coated DBM Powder

Bovine DBM (Intergraft) (manufactured by Cellu Med SOP regulation) and 1%, 5%, and 10% ECM hydrogels were prepared. ECM hydrogels and Bovine DBM (Intergraft) were mixed in a paste mixer (Conductec, PDM-300V) at a mixing ratio of 1: 1 (v / v). The mixture was lyophilized at -70 ° C for 72 hours, dispersed with a mortar or a mixer, and then separated into 100 ~ 300 μm sized Intergraft / ECM using a microsieve (CISA) having a sieve size of 300 μm. 1 g of Intergraft / ECM prepared from 1%, 5%, and 10% ECM hydrogels was placed in a container containing 10 ml of phosphate buffer solution (pH = 7.4), then placed in a 37-well water bath at 15 rpm for 6 hours . After removal of the phosphate buffer solution, the mass of Intergraft / ECM prepared with 1%, 5%, and 10% ECM hydrogels absorbing moisture was determined and the water uptake was analyzed.

As a result, water absorption rate of Intergraft / ECM prepared with 1%, 5%, and 10% ECM hydrogels was measured. As a result, it was confirmed that increase of ECM hydrate concentration increased water absorption rate.

Example 3 Analysis of BMP2 Emission from ECM / BMP2 Coated DBM Powder

Bovine DBM (Intergraft) (manufactured by Cellu Med SOP regulation) and 1%, 5%, and 10% ECM hydrogels were prepared. 1%, 5%, and 10% ECM hydrogels were mixed with BMP-2 at a concentration of 10 ug / ml. ECM hydrogels to which BMP-2 was added and Bovine DBM (Intergraft) were mixed in a paste mixer (Conductec, PDM-300V) at a mixing ratio of 1: 1 (v / v). The mixture was lyophilized at -70 ° C for 72 hours, dispersed with a mortar or a mixer, and then subjected to a microsieve (CISA) having a sieve size of 300 μm to separate only Intergraft / ECM / BMP having a size of 100 to 300 μm. 1 g of Intergraft / ECM / BMP prepared from 1%, 5%, and 10% ECM hydrogels was placed in a container containing 5 ml of phosphate buffer solution (pH = 7.4), and the mixture was placed in a 37-well water bath and rotated at 15 rpm . The amount of BMP2 contained in the buffer was measured using a BMP2 Quantikine ELISA kit (R & D system, USA).

The release of BMP2 from Intergraft / ECM / BMP prepared with 1%, 5%, and 10% ECM hydrogels was 75%, 60%, and 35%, respectively, , The rapid initial mass release was reduced. BMP2 release of Intergraft / ECM / BMP made from 10% ECM hydrogels and 5% ECM hydrogels lasted up to 18 days (Figure 5).

Those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

The bone graft material according to the present invention is capable of minimizing the disadvantage that the bone graft protein is degraded while the effect is not maintained while treating bone defects by simple injection of the conventional bone graft forming protein, The BMP-2 can achieve the desired therapeutic effect even with a small amount of BMP-2, and thus can reduce the cost incurred by applying a large amount of BMP-2.

Claims

A method for preparing bone graft coated with an extracellular matrix (ECM) coated with an osteogenic protein (BMP) comprising the steps of:
(a) mixing a bone graft material with an osteogenic protein / extracellular matrix hydrogel;
(b) lyophilizing the mixture of step (a); And
(c) pulverizing the lyophilizate of step (b) and separating the bone graft material coated with the osteogenic protein / extracellular matrix hydrogel by a micro sieve.

The method according to claim 1,
RTI ID = 0.0 > 1, < / RTI > wherein the bone graft material comprises a demineralized bone matrix.

The method according to claim 1,
Wherein the extracellular matrix hydrogel of step (a) is prepared by the following steps:
a) preparing a demineralized bone matrix solution by adding a citric acid solvent at a concentration of 3M to 5M to the demineralized bone matrix;
b) separating the solution containing the soluble material of the demineralized bone matrix from the demineralized bone matrix solution and the insoluble material;
c) neutralizing the solution comprising the soluble material;
d) drying the result of step c);
e) rehydrating the result of step d); And
f) repeating the step of freezing the solution re-hydrated in step e) at a temperature of -80 ° C to -60 ° C and thawing it.

The method according to claim 1,
Wherein the concentration of the extracellular matrix in the mixture of step (a) is 1 to 10%.

The method according to claim 1,
Wherein the bone forming protein / extracellular matrix hydrogel and bone graft material of step (a) are contained in a weight ratio of 1: 0.1-10.

The method according to claim 1,
Wherein the osteogenic protein of step (a) is BMP-2, BMP-4, BMP-7 or BMP-14.

The method according to claim 1,
Wherein the concentration of the osteogenic protein of step (a) is 1-20 占 퐂 / ml.

The method according to claim 1,
Wherein the microsieve in the step (c) has a sieve size of 200 to 300 mu m.

8. A bone graft material coated with an extracellular matrix (ECM) to which a bone morphogenetic protein (BMP) is added, which is prepared according to the method of any one of claims 1 to 8.

10. The method of claim 9,
Wherein the bone graft material is a powder having a size of 200 to 300 mu m.