CN101773687B - Preparation method of composite soft-tissue patch - Google Patents
Preparation method of composite soft-tissue patch Download PDFInfo
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- CN101773687B CN101773687B CN 200910254641 CN200910254641A CN101773687B CN 101773687 B CN101773687 B CN 101773687B CN 200910254641 CN200910254641 CN 200910254641 CN 200910254641 A CN200910254641 A CN 200910254641A CN 101773687 B CN101773687 B CN 101773687B
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Abstract
The invention discloses a preparation method of a composite soft-tissue patch. Sustained-release microspheres containing human cell culture secretion are mixed with gel solution, then the mixture is compounded with an acellular dermal matrix under vacuum, and after drying and sterilization, the composite soft-tissue patch is obtained. The prepared composite patch can improve the biocompatibility and the bioactivity of the dermal matrix effectively. The experiment shows that compared with the single acellular dermal matrix, the patch can promote cell proliferation and collagen formation effectively and has better biocompatibility and better tissue remolding. The patch can be widely applied to closure of various wound surfaces, repair of various soft-tissue defects and reinforcement of weak places and can be prepared into micro particles to be used for filling various fine and weak or dented places by injection, thus having wider application prospect in clinic.
Description
Technical field
The invention belongs to the tissue engineering technique field of bio-medical material, be specifically related to a kind of preparation method of the complex tissue sticking patch of repairing for soft tissue defects.
Background technology
Damaged, the weakness of soft tissue is FAQs clinically, and the reason that causes has birth defect, pathological factor and old and feeble etc., and clinical manifestation is: hernia, fistula, cicatrix and wrinkle etc.Damaged, the weakness of this class soft tissue usually can't self-healing, has influence on greatly function and the outward appearance of corresponding organ tissue.Mainly rely on clinically at present tissue patch filling reparation, therefore the research and development of tissue patch become one of focus of modern bio-medical material.
The kind of tissue patch is a lot, has by the material classification: nylon sticking patch, polypropylene sticking patch, expanded polytetrafluoroethylsealing sticking patch, biological sticking patch, composite patch etc.Abiotic sticking patch wherein have biocompatibility relatively poor, can not degrade, affect the problems such as postoperative life quality.In recent years, what the biological sticking patch that comes into the market mostly was allosome/xenogenesis takes off cell products and derived product thereof, as: take off the cell human dermis, take off cell cattle corium etc.Simple takes off cell material because also removed a large amount of active substances in the process of removing cell, and biological activity reduces greatly; But the improvement by to method for removing cells can effectively improve the biological activity that takes off cell material, in order further to improve the character of taking off cell material, makes it possess better biocompatibility simultaneously, realizes certain physiological function, and composite patch becomes the emphasis of research.
Chinese patent (200610027044.9) discloses the allosome that a kind of human fibroblasts modifies/xenogenesis acellular dermal substitute, with fibroblast and the compound cultivation of acellular dermal matrix, make acellular dermal surface formation single or multiple lift human fibroblasts, affinity and the vigor of acellular dermal have been improved, as dermal substitute.The deficiency of the method is: prepared dermal substitute, and its range of application only limits to skin histology; This dermal substitute contains cell, easily produces immunologic rejection in clinical practice, therefore is difficult to be applied to the reparation of in-vivo tissue; In addition, celliferous sticking patch complicated process of preparation, production cost is high, and difficult quality is controlled, and the industrialization bottleneck is not yet broken through.
Chinese patent (200610153403.5) discloses a kind of surgical patch with bioactivator, and this sticking patch has the function that discharges antiinflammatory, anti-platelet agents, anticoagulant, fibrinolytic agent, cell cycle inhibitor and/or antiproliferative; But it only limits to vascular patch, and just adopts simple medicine coating process preparation, can't realize the continuous action of medicine.
Through retrieval, up to the present there is no the requirement that a kind of sticking patch can satisfy clinical practice fully.
Summary of the invention
For the deficiencies in the prior art, the preparation method that the purpose of this invention is to provide a kind of composite soft-tissue patch, the gained soft-tissue patch is not only had repair the function of filling, also have the ability that promotes cell proliferation and secretion substrate, biocompatibility and tissue reconstruction better effects if in clinical manifestation.
Composite soft-tissue patch preparation method provided by the present invention, employing has the dermal matrix of processing through taking off cell, it is characterized in that, to contain the sustained-release micro-spheres that human body cell is cultivated secretions, be mixed in gel solution, compound under vacuum condition with acellular dermal matrix again, obtain can be used for the composite soft-tissue patch that human body soft tissue is repaired after the drying sterilization.Described acellular dermal matrix can derive from xenogenesis or allosome, has natural three dimensional structure, and its porosity can reach more than 90%, is conducive to cell and grows into, and is a kind of well behaved biologic bracket material.Described human body cell is cultivated secretions, the Cell health factor that the various active factor of secreting in incubation for human body cell and stromatin consist of; Institute's cultured cells is according to sticking patch purposes needs, can be cells all types of in tissue; Collect the secretions of these cell culture, with the compound sustained-release micro-spheres that contains cell culture secretions that becomes of microsphere; Described microsphere can adopt any or several mixture of glycidyl methacrylate dextran, polylactic acid, polyglycolic acid or gelatin to be prepared from.Prepared tissue patch has higher biological activity, and slowly release cells is cultivated secretions and promoted cell proliferation and matrix secretion in implant into body three months, promotes tissue reconstruction, thereby reaches better clinical therapeutic efficacy.
The concrete steps of composite soft-tissue patch preparation method of the present invention comprise:
Step 1, preparation acellular dermal matrix: get the mammiferous fresh skin of health (people, pig, cattle etc.), remove subcutaneus adipose tissue and epidermis after cleaning, keep the thick skin corium skin graft of 0.1mm～2mm, clean with aseptic PBS solution respectively with deionized water, soak abundant swelling in 4 ℃ of deionized waters; Be placed in-80 ℃ freezing more than 30 minutes, melt to organizing to take out after complete deep colling, can effectively destroy cell, cellular content is come out, be convenient to next step removing, this frozen-thaw process is at least one times; Adopting W/V is 0.1%～0.3% trypsin solution digestion skin graft again, removes being connected between collagen protein and other albumen, and the removal of antigen protein is convenient in crumbly texture; Detergent solution with any or several mixing that contain Triton X-100/200, NaTDC or sodium lauryl sulphate cleans skin graft, removes most antigenic component, still stays part small fragment nucleic acid; With the DNA enzymatic solution digestion of 40～150U/ml, remove residual DNA, along with digestion time can be suitably shortened in the increase of temperature again; With the NaOH solution ablation corium skin graft 1h of 1M, to remove the virus in corium, guarantee the use safety of prepared dermal matrix; At last skin graft is cleaned with PBS solution and pure water respectively, after lyophilization, sterilization, 4 ℃ save backup; Resulting acellular dermal matrix has higher biological activity and biocompatibility, and its porosity is more than 90%.
Step 2, preparation cell culture secretions: the culture fluid under changing in the collecting cell incubation, cell culture processes can be with reference to " tissue engineering philosophy and technique " (publication in 2004 of banket publishing house of The Fourth Military Medical University) or other prior arts; Concentrate (ultrafiltration post can adopt 30K aperture) by hyperfiltration process, desalt with washed with de-ionized water; Adopt the protein purification instrument to remove bovine serum albumin, remaining protein ingredient is the cell culture secretions that contains required Cell health factor, preserves after filtration sterilization;
step 3, preparation contains the sustained-release micro-spheres of cell culture secretions: with reference to " experimentation of the biological controlled-released promotion paradenlal tissue regeneration of somatomedin " (Chen Faming, thesis for the doctorate) or other prior arts, micro-sphere material can adopt the glycidyl methacrylate dextran, polylactic acid, polyglycolic acid, or the mixing of any or two kinds of gelatin, the particle diameter of prepared microsphere is 10nm～3um, after the lyophilizing sterilization, use the method for adsorption from aqueous solution under aseptic condition, make the cell culture secretions that contains 100～500mg in the 1g microsphere, namely get the sustained-release micro-spheres that contains cell culture secretions after lyophilizing,
Step 4, preparation composite soft-tissue patch: any of employing collagen, cellulose, alginic acid, hyaluronic acid or chitosan or a several mixture are raw material, preparation W/V is 0.2～1.5% gel solution, add therein the sustained-release micro-spheres that contains cell culture secretions, the final concentration that makes cell culture secretions is 50～200mg/ml, evenly cover after mixing and be applied to the acellular dermal matrix surface, the gel solution that contains cell culture secretions microsphere fully is penetrated in the hole of acellular dermal, and covering the amount of being coated with is 0.5～1ml/cm
2, be composite soft-tissue patch after drying.
The preservation of composite soft-tissue patch of the present invention and use: should preserve under 0～8 ℃; During use, sticking patch is cut into required size and is placed in sterile chamber, the normal saline immersion 5～30min with 10～50 times of amounts can be used for the sealing of various wound surface, the repairing of soft tissue defects and the enhancing of weakness; Sticking patch fragment and cutting residue can adopt injection system to be used for the filling of various tiny soft tissue weaknesses or recess after crushed.
The composite soft-tissue patch of the present invention's preparation has kept the good three dimensional structure of acellular dermal matrix, for adhering to of cell provides natural three dimensions; Due to the use of uniting of the methods such as enzyme processing, detergent cleaning and alkali treatment, effectively removed antigenic component, can not cause obvious immunological rejection; The gel that compound tense adopts can promote growing into of cell; Carry a large amount of cell growth factor and extracellular matrix components in sustained-release micro-spheres and can promote cell proliferation and matrix secretion; Sustained-release micro-spheres is adsorbed onto the release time that can effectively extend the emiocytosis thing in the hole of acellular dermal, makes the effect of emiocytosis thing more stable lasting.The present invention is not owing to adopting the compound cultivation of cell, makes that making is easier, cost is lower, quality is easily controlled, it is more convenient to use.Experiment shows, compares with simple acellular dermal matrix, and sticking patch of the present invention can effectively promote the secretion of propagation and the substrate of cell, has better biocompatibility and more excellent tissue reconstruction.Sticking patch of the present invention can be widely used in the sealing of various wound surface, the repairing of soft tissue defects and the enhancing of weakness, also can be made into powder and is used for the filling of various tiny weaknesses or recess by injection, has clinically application prospect widely.
The specific embodiment
Below in conjunction with instantiation, technical solution of the present invention is described in further detail.
Embodiment 1,
Step 1, preparation acellular dermal matrix: get healthy fresh porcine skin, remove subcutaneus adipose tissue and epidermis with the bark fetching drum, keep the thick skin corium of 0.1mm, clean with deionized water, clean with aseptic PBS solution again, after 4 ℃ of deionized waters soak abundant swelling, be placed in-80 ℃ freezing more than 30 minutes, be placed in 37 ℃ of environment and melt, 2 times repeatedly to organizing to take out after complete deep colling; Adopt the trypsin solution of 0.1% (W/V) to digest skin graft 1 day; Use subsequently 0.02% (W/V) Triton X-100/200 solution to clean 1 day; 37 ℃ of digestion of the DNA enzymatic solution of employing 40U/ml 2 hours; NaOH solution soaking corium skin graft 1h with 1M; After cleaning with PBS solution and pure water respectively, after lyophilization, sterilization, save backup in 4 ℃; The acellular dermal matrix porosity for preparing by the method is 91%;
Step 2, preparation cell culture secretions: carry out the fibroblast cultivation with reference to " tissue engineering philosophy and technique " (publication in 2004 of banket publishing house of The Fourth Military Medical University), collect the culture fluid under changing; The employing hyperfiltration process is concentrated, and washed with de-ionized water desalts, and the ultrafiltration post adopts the 30K aperture; Adopt protein purification instrument (AKTA PRIME) to remove bovine serum albumin, remaining protein ingredient is required people's cell culture secretions, surveys secretion content (in Tot Prot), and concentration transfers to 200mg/ml, preserves after filtration sterilization;
Step 3, preparation contain the sustained-release micro-spheres of cell culture secretions: with reference to " experimentation of the biological controlled-released promotion paradenlal tissue regeneration of somatomedin " (Chen Faming, thesis for the doctorate) method in prepares glycidyl methacrylate dextran microsphere, the mean diameter of microsphere is 50～100nm, after the lyophilizing sterilization, add the aqueous solution of 1ml cell culture secretions under aseptic condition in the 1g microsphere, placed one day under 4 ℃, must contain the sustained-release micro-spheres of cell culture secretions after lyophilizing;
Step 4, preparation composite soft-tissue patch: adding cell culture secretions final concentration in W/V is 0.3% collagen solution is the sustained-release micro-spheres that contains cell culture secretions of 80mg/ml, after mixing, this gel solution is evenly covered and be applied to the acellular dermal matrix surface, covering the amount of being coated with is 0.6ml/cm
2, make under vacuum condition in its hole that fully is penetrated into acellular dermal, namely get composite soft-tissue patch after lyophilization.
The composite soft-tissue patch thickness of this example preparation is 0.1～0.15mm, and fracture tensile strength is greater than 0.1Mpa.Sticking patch is preserved under 4 ℃ of conditions, during use, the sticking patch taking-up is cut into suitable size as required and is placed in sterile chamber, adds the normal saline of 10～20 times of amounts to soak 10min.This sticking patch can be used for the reparation of soft tissue defects in body and the enhancing of soft tissue weakness, as: the sealing of wound surface etc. after hernia reparation, tumor operation; Its sticking patch fragment and cutting residue can be used for local the filling after crushed, as injecting reduce wrinkle etc.
Embodiment 2,
Step 1, preparation acellular dermal matrix: get healthy abortive calfskin, manual subcutaneus adipose tissue and the epidermis removed after cleaning, keep the thick skin corium of 1mm, clean with deionized water, clean with aseptic PBS solution again, after 4 ℃ of deionized waters soak abundant swelling, be placed in-80 ℃ freezing more than 30 minutes, be placed in 37 ℃ of environment and melt, 3 times repeatedly to organizing to take out after complete deep colling; Adopt the trypsin solution of 0.25% (W/V) to digest 2 hours, then cleaned 8 hours with 0.05% sodium dodecyl sulfate solution; 37 ℃ of digestion of the DNA enzymatic solution of employing 80U/ml 2 hours; NaOH solution ablation corium skin graft 1h with 1M; Corium after processing after lyophilization, sterilization, saves backup in 4 ℃ after cleaning with PBS solution and pure water respectively; The acellular dermal matrix porosity for preparing by the method is 93%;
Step 2, preparation cell culture secretions: with reference to the comparative study of the spready hide sheet method in " Chinese Reconstructive surgery " (06 phase in 2004) and lingel method cultivation epidermis cell, carry out epidermis cell and cultivate, collect the culture fluid under changing; Carry out the fibroblast cultivation by example 1, collect the culture fluid of changing; Adopt hyperfiltration process concentrated respectively, washed with de-ionized water desalts, and the ultrafiltration post adopts the 30K aperture; Adopt protein purification instrument (AKTA PRIME) to remove bovine serum albumin, obtain respectively two kinds of required cell culture secretions, survey respectively secretion content (in Tot Prot), preserve after filtration sterilization;
step 3, preparation contains the sustained-release micro-spheres of cell culture secretions: with reference to " sustained-release micro-spheres of preparation composite growth factor is also investigated it to the impact of cell " (yellow sand, banket etc., " Shanghai biomedical engineering " magazine the 25th the 4th phase of volume in 2004) preparation method of gelatine microsphere in, the preparation mean diameter is the gelatine microsphere of 100～500nm, after the lyophilizing sterilization, add in the 2g microsphere under aseptic condition and contain the aqueous solution that the 250mg epidermis cell is cultivated secretions and contained 100mg fibroblast cultivation secretions, placed one day under 4 ℃, namely get the sustained-release micro-spheres that contains cell culture secretions after lyophilizing,
Step 4, preparation composite soft-tissue patch: in containing the mixed gel solution that W/V is 0.15% hyaluronate sodium and 0.15% collagen, add the sustained-release micro-spheres that contains cell culture secretions, the final concentration that makes cell culture secretions is 120mg/ml, after mixing, this gel solution is evenly covered and be applied to the acellular dermal matrix surface, covering the amount of being coated with is 1ml/cm
2, making under vacuum condition in its hole that fully is penetrated into acellular dermal, lyophilizing namely gets composite soft-tissue patch.
The composite soft-tissue patch thickness of this example preparation is 1～1.2mm, and fracture tensile strength is greater than 0.2Mpa; Sticking patch is preserved under 4 ℃ of conditions, during use, the sticking patch taking-up is cut into suitable size as required and is placed in sterile chamber, adds the normal saline of 10～20 times of amounts to soak 15min.This sticking patch is applicable to the sealing of human body skin wound surface, can effectively promote the healing of refractory wound surface, chronic ulcer.
Claims (1)
1. the preparation method of a composite soft-tissue patch, employing has the dermal matrix of processing through taking off cell, it is characterized in that, to contain the sustained-release micro-spheres that human body cell is cultivated secretions, be mixed in gel solution, compound with acellular dermal matrix under vacuum condition again, obtain composite soft-tissue patch after the drying sterilization; Concrete steps comprise:
Step 1, preparation acellular dermal matrix: get after fresh skin cleans, remove subcutaneus adipose tissue and epidermis, keep the thick skin corium skin graft of 0.1mm～2mm, clean with deionized water and aseptic PBS solution respectively, soak abundant swellings in 4 ℃ of deionized waters; Be placed in-80 ℃ freezing more than 30 minutes, melt to organizing to take out after complete deep colling; After adopting again W/V to be 0.1%～0.3% trypsin solution digestion skin graft, clean skin graft with the de-sludging agent solution; With the digestion of the DNA enzymatic solution of 40～150U/ml, with the NaOH solution ablation corium skin graft 1h of 1M, at last skin graft is cleaned with PBS and pure water respectively again, after lyophilization, sterilization, 4 ℃ of the acellular dermal matrixes that obtain are saved backup;
Step 2, preparation cell culture secretions: the culture fluid under changing in the collecting cell incubation, concentrate by hyperfiltration process, desalt with washed with de-ionized water; Adopt the protein purification instrument to remove bovine serum albumin, remaining protein ingredient is cell culture secretions, preserves after filtration sterilization;
Step 3, preparation contain the sustained-release micro-spheres of cell culture secretions: be that the microsphere of 10nm～3um is after the lyophilizing sterilization with particle diameter, use the method for adsorption from aqueous solution under aseptic condition, make the cell culture secretions that contains 100～500mg in the 1g microsphere, be the sustained-release micro-spheres that contains cell culture secretions after lyophilizing;
Step 4, preparation composite soft-tissue patch: in W/V is 0.2～1.5% gel solution, add the sustained-release micro-spheres that contains cell culture secretions, the final concentration that makes cell culture secretions is 50～200mg/ml, evenly cover after mixing and be applied to the acellular dermal matrix surface, covering the amount of being coated with is 0.5～1ml/cm
2, under vacuum condition, it is fully permeated, be composite soft-tissue patch after drying.
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| CN102172418B (en) * | 2011-02-18 | 2014-01-01 | 上海交通大学医学院附属新华医院 | Acellular matrix material capable of sustainedly releasing growth factors |
| CN105833353B (en) * | 2016-05-09 | 2018-04-20 | 拜欧迪赛尔（北京）生物科技有限公司 | A kind of preparation of bioengineering acellular dermal matrix and purposes |
| CN105903080B (en) * | 2016-05-23 | 2019-04-02 | 苏州恒瑞迪生医疗科技有限公司 | A kind of breast sticking patch and preparation method thereof |
| CN107376023A (en) * | 2017-08-31 | 2017-11-24 | 上海市第六人民医院 | A kind of preparation method of timbering material suitable for urethra reconstruction |
| CN109529106B (en) * | 2018-11-14 | 2021-09-10 | 山东隽秀生物科技股份有限公司 | Preparation method of chronic wound repair matrix |
| JP2022516123A (en) * | 2018-12-28 | 2022-02-24 | エクセル メッド、エルエルシー | Biological scaffold and its manufacturing method |
| CN110960731A (en) * | 2019-12-12 | 2020-04-07 | 成都奇璞生物科技有限公司 | Preparation method of medical surgical biological patch |
| CN114146221A (en) * | 2021-12-09 | 2022-03-08 | 杭州帕莱拉医疗科技有限公司 | Injectable dextran hydrogel microsphere filling agent and preparation method thereof |
| CN115054732B (en) * | 2022-06-07 | 2023-10-13 | 东华大学 | Suture-free multi-layer drug-loaded myocardial patch and preparation method thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007051221A1 (en) * | 2005-11-04 | 2007-05-10 | Craig Mclachlan | Substrate for tissue growth |
| CN101366978A (en) * | 2008-09-03 | 2009-02-18 | 陕西瑞盛生物科技有限公司 | Fine particle tissue hydraulic fill for injection and preparation method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007051221A1 (en) * | 2005-11-04 | 2007-05-10 | Craig Mclachlan | Substrate for tissue growth |
| CN101366978A (en) * | 2008-09-03 | 2009-02-18 | 陕西瑞盛生物科技有限公司 | Fine particle tissue hydraulic fill for injection and preparation method thereof |
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