Serum free medium of cell suspension culture and adherent culture and preparation method thereof
Technical field
The present invention relates to the medical experiment articles for use, especially relate to a kind of being used at the cell suspension culture of vitro culture humans and animals tissue and cell and serum free medium of adherent culture and preparation method thereof.
Background technology
In medical experiment, the tissue of humans and animals and cell except that the basic medium that need be rich in amino acid, inorganic salt, VITAMIN, lipid material and energy matter (as carbohydrate), also need to provide the animal serum of other nutrition, cytokine and hormone when vitro culture.Traditional cell and tissue culture all will be used the animal serum of 5-20%, but because the composition of animal serum is very complicated, so far do not understand fully composition wherein as yet fully, for example contain 500 multiple proteins in serum, wherein some proteinic function also imperfectly understands.Thereby in the medical science experiment, often, be difficult for reaching stdn because of the serum difference that adds causes experimental result to produce some differences, influence the repeatability and the accuracy of experimental result.As the experiment of some research polypeptide factor effect, because of containing the indefinite polypeptide cytokines of concentration, hormone or other material in the serum, they may influence the function etc. of growth, immunity identification, the specific polypeptide factor and the cell surface receptor of cell.Also there is supressor in addition in the serum, and antigen and antibody, they can disturb external immunization experiment result.
The external research that has just begun to carry out the serum-free culture method as far back as 1979.Now external serum free medium kind of producing is a lot, be applicable to the serum free medium of insect cell, hybridoma, skin epithelial cells, hematopoietic cell, tumour cell, neurocyte, liver cell, endotheliocyte, embryonic stem cell respectively, there is following shortcoming jointly in they:
(1) is only applicable to the cell of a certain particular tissue type, as neurocyte, liver cell, epithelial cells, endotheliocyte, embryonic stem cell;
(2) be respectively applied for the adherent culture except that the specific serum free medium of minority, still do not have the adherent culture that a kind of cell attachment serum free medium is applicable to the broad variety cell.Have as can be used for the serum free medium that cell attachment cultivates abroad: skin epithelial cells serum free medium (Keratinocyte-SerumFree Media, Keratinocyte-SFM), scavenger cell serum free medium (Macrophage-SFM), endotheliocyte serum free medium (Endothelial-SFM).
The applicant has applied for a patent of invention " a kind of serum free medium and concentrated solution and preparation method thereof " (application number: 02157709.9) on December 17th, 2002, the main raw material of five kinds of compositions such as the bovine serum albumin solution in this patent of invention, insulin solutions, purifying human transferrin solution, cholesterol solution, hydrogen peroxide enzyme solution all is Powdered, can weighing, do not contain polypeptide factor and hormone substance, thereby both can avoid the unstable brought because of serum lot number difference, being unlikely again influences experimental result.The serum free medium of this patent of invention is to make cell keep normal growth under the situation of getting rid of serum interference, thereby makes experimental result science and accurate more, and better repeatability is arranged, and is applicable to the growth of polytype tissue and cell.But its shortcoming is to be not suitable for carrying out the cell attachment cell cultures.
Summary of the invention
The object of the present invention is to provide a kind of tissue and the cell suspension culture of cell and serum free medium of adherent culture and preparation method thereof that is applicable to than broad variety, it can make cell keep normal growth under the situation of getting rid of serum interference, thereby make experimental result science and accurate more, and better repeatability is arranged.
The object of the present invention is achieved like this: the prescription of serum free medium of the present invention comprises the bovine serum albumin solution in final concentration: 5-10mg/ml, insulin solutions: 8-20 μ g/ml, purifying human transferrin solution: 1-30 μ g/ml, cholesterol solution: 20-60 μ g/ml and hydrogen peroxide enzyme solution: 20-60 μ g/ml is characterized in that: also comprise sodium selenite solution: 17.3-34.6 μ g/ml and 3-mercaptoethanol solution (1%): 0.35-0.70ml.This serum free medium is suitable for cell suspension culture.
In the serum free medium that is suitable for cell suspension culture of the present invention, also can add cell Fibronectin: 25-50 μ g/ml and short anchoring factor (PAF) in final concentration.It is suitable for cell attachment and cultivates.
The preparation method who is suitable for the serum free medium of cell suspension culture of the present invention is:
(1), compound concentration is respectively bovine serum albumin (the BovineSerum Albumin of 50-100mg/ml according to a conventional method, abbreviation BSA) Regular Insulin (Insulin of solution, 80-400 μ g/ml, abbreviation Ins) purifying human transferrin (the Human Transferrin of solution, 10-300 μ g/ml, abbreviation TF) cholesterol (Cholesterol of solution, 200-600 μ g/ml, abbreviation Chol) catalase (Catalase of solution and 200-600 μ g/ml, abbreviation Cat) solution all is dissolved in Yi Sikefu improvement cutter than Ke Shi substratum;
(2), the preparation of Sodium Selenite (Sodium Selenite, abbreviation SS) solution: the 1.73mg Sodium Selenite powder with commercially available is dissolved in the 10ml triply distilled water Entkeimung, 4 ℃ of refrigerators preservations;
(3), the preparation of 3-mercaptoethanol (2-mercaptoethanol, abbreviation 2-ME) solution: commercially available 3-mercaptoethanol is added in the triply distilled water, make into 1% solution, be stock solution, Entkeimung is put 4 ℃ of refrigerators and is preserved;
(4), above-mentioned seven kinds of solution are mixed by formula concentration, again with Yi Sikefu improvement cutter than Ke Shi substratum (Iscove ' s modified Dulbecco ' s media, abbreviation IMDM) dilution is the 500ml/ bottle, promptly get the cell suspension culture serum free medium (Suspension-Serum Free Media, SP-SFM).
The preparation method who is suitable for the foster base of cell attachment cultivation serum-free wall of the present invention is:
(1), compound concentration is respectively the bovine serum albumin solution of 50-100mg/ml, the insulin solutions of 80-400 μ g/ml, the purifying human transferrin solution of 10-300 μ g/ml, the cholesterol solution of 200-600 μ g/ml and the hydrogen peroxide enzyme solution of 200-600 μ g/ml according to a conventional method, all is dissolved in Yi Sikefu improvement cutter than Ke Shi substratum;
(2), the preparation of sodium selenite solution: commercially available Sodium Selenite powder 1.73mg is dissolved in the 10ml triply distilled water Entkeimung, 4 ℃ of refrigerators preservations;
(3), the preparation of 3-mercaptoethanol solution: commercially available 3-mercaptoethanol is added in the triply distilled water, make into 1% solution, be stock solution, Entkeimung is put 4 ℃ of refrigerators and is preserved;
(4), the preparation of cell Fibronectin solution:
1., people's marrow fibroblast culture supernatant: obtain BMNC with lymphocyte separation medium (Ficoll-Hypague) density gradient centrifugation, be incubated in the plastic culture bottle that is covered with 4% poly-lysine in advance with 1 * 106 cell/ml concentration, add 10% people AB serum and 10-6M hydrocortisone (final concentration), cultivated 5 days, form adherent individual layer, inhale and remove supernatant, change the cell suspension culture serum free medium and continue to cultivate 2 days, the results supernatant liquor is further purified;
2., 1 liter of people's marrow fibroblast culture supernatant being added gelatin-agarose (Sepharose) that the 1ml bovine serum albumin handles hatched 24 hours for 4 ℃, separate gelatin-agarose (Agarosc) pearl with the centrifugation method in conjunction with the cell Fibronectin, with the can of 10ml pearl in the chromatography column of 1.5cm diameter; This post is at room temperature used the 0.15M NaCl of 4 times of post bed capacity, 10mM Tutofusin tris-hydrochloric acid (Tris-HCl), the pH7.0 washing is with damping fluid C[4M urea, 0.5MNaCl, 50mM hexahydroaniline propane sulfonic acid (CAPS)], the pH11.0 elution; Determine protein peak, the each several part that will contain the cell Fibronectin mixes, and with buffer A (0.15M NaCl, 1mM CaCl2,10mM hexahydroaniline propane sulfonic acid, readjustment pH to 11.0) dialysis, detects protein concn, makes into 0.125g/ml concentration, is stored in-70 ℃;
(5), above-mentioned eight kinds of solution pressed formula rate mix, be diluted to the 500ml/ bottle with Yi Sikefu improvement cutter than Ke Shi substratum again, promptly get cell attachment cultivation serum free medium (Adhesion-SerumFree Media, AD-SFM);
(6), the preparation of short anchoring factor:
1., people's marrow fibroblast culture supernatant: obtain BMNC with the lymphocyte separation medium density gradient centrifugation, be incubated in the plastic culture bottle that is covered with 4% poly-lysine in advance with 1 * 106 cell/ml concentration, add 10% people AB serum and 10-6M hydrocortisone (final concentration), cultivated 5 days, form adherent individual layer, inhale and remove supernatant, change the cell suspension culture serum free medium and continue to cultivate 2 days, the results supernatant liquor is further purified;
2., granulated glass sphere affinity chromatography: glass microballon with 0.6M NaHCO3 (pH8.0) washing, is adorned post (5cm * 50cm), use 0.6M NaHCO3 equilibrate overnight, flow velocity 100ml/ hour.People's marrow fibroblast culture supernatant is adjusted to pH8.0 with 0.1N NaOH, filter, with 100ml people's marrow fibroblast culture supernatant with sample on the 100ml/ speed at one hour rating, elution peak (behind 65kd and the 75kd) appears, with following damping fluid (all containing tolylsulfonyl fluorine (PMSF)) wash-out (100ml/ hour):
A.200ml?0.6M?NaHCO3·pH8.0
B.100ml?0.6M?NaHCO3-0.2M?Na2CO3,pH9.3-9.5
C.100ml?H2O
D.500ml 0.2M K2CO3, pH11.0 will mix with the each several part of 0.6M NaHCO3-0.2M Na2CO3 elution, carry out next step purifying;
3. concanavalin A-agarose column/diethylaminoethyl-(DEAE) chromatography:
(2.5cm * 20cm) (2.5cm * 3cm), the 2.5cm of can thereon * 16cm concanavalin A-agarose column layer uses the phosphoric acid buffer balance, 30ml/ hour to chromatography column then with diethylaminoethyl--agarose can bottom;
Urge each part (about 200ml) of anchoring factor with 0.6M NaHCO3-0.2M Na2CO3 from containing of glass bead column elution and be applied to concanavalin A/diethylaminoethyl-post, 30ml/ hour, press the laxative remedy elution:
1) 30ml 0.25M sodium phosphate (Na/pi), pH6.0,30ml/ hour;
2) 200ml 25mM Na/Pi, pH6.0,15ml/ hour;
3) 250ml contains the 25mM Na/Pi of 50mM seminose, pH6.0,30ml/ hour;
4) 30ml 25mM Na/Pi, pH6.0,30ml/ hour;
5) 60ml contains the 25mM Na/Pi of 100mM NaCl, pH6.0,30ml/ hour;
6) 100ml contains the 25mM Na/Pi of 0.5M Alpha-Methyl mannoside and 1M NaCl, pH6.0,30ml/ hour;
7) 100ml contains the 0.15M NaCl 20mM Tutofusin tris of (containing 1mM MgC12,1mM CaCl2 and 1mM MnCl2), pH7.3.Contain the elution peak 25mM Na/Pi elution that contains 100mM NaCl of the material of PAF;
4. heparin-agarose column chromatography:
Heparin-agarose chromatography column (the dress of 0.7cm * 10cm) post, and with the 25mMNa/Pi that contains 100mM NaCl, pH6.0 balance (15ml/ hour), the part difference (not mixing) that contains short anchoring factor of concanavalin A/diethylaminoethyl-purifying goes up sample to the heparin-agarose post, 7.5ml/ hour, by the laxative remedy elution, promptly get and urge anchoring factor:
1) 20ml contains the 25mM Na/Pi of 100mM NaCl, pH6.0 (15ml/ hour);
2) 20ml contains among the 50mM Na/Pi of 100mM NaCl, pH7.0 (4ml/ hour);
3) 20ml contains among the 50mM Na/Pi of 1M NaCl, pH7.4 (15ml/ hour);
At the bottom of overlaying the culturing bottle bottle with short anchoring factor, cultivate with cell attachment cultivation serum free medium mixed culture cell injection culturing bottle again (7), earlier.
The present invention has two kinds of preparations: cell suspension culture serum free medium and cell attachment are cultivated serum free medium.The former is to be raw material with bovine serum albumin powder, insulin powder, purifying human transferrin powder, cholesterol powder, catalase powder, Sodium Selenite powder and 3-mercaptoethanol solution, forms by certain prepared.The latter is divided into two portions, and a part is the substratum part, is based on the cell suspension culture base, adds the cell Fibronectin and makes; Another part is an extention, is the short anchoring factor that is prepared from the gel-filtration method.These raw materials or be commercially available, or self-control purifying all can weighings, do not contain polypeptide factor and hormone substance, thereby both can avoid the unstable brought because of serum lot number difference, are unlikely to influence experimental result again.Therefore cell suspension culture and cell attachment cultivation serum free medium is to make cell keep normal growth under the situation of getting rid of serum interference, thereby makes experimental result science and accurate more, and better repeatability is arranged.It also has following characteristics:
(1) is added with the hydrogen peroxide enzyme solution in the prescription: in cell suspension culture and cell attachment cultivation serum free medium, add the hydrogen peroxide enzyme solution and can promote the long term growth and the clone of cell, and can replace bovine serum albumin and tyrosine.Studies have shown that hydrogen peroxide is cell growth and clone's a main toxicant.Tyrosine in the substratum, tryptophane, riboflavin, ascorbate salt etc. all can cause the formation of hydrogen peroxide, hydrogen peroxide can be by the damage of the oxidation of the oxidation of unsaturated fatty acids on the cytolemma, cell protein and/or DNA and is caused the death of cell, and catalase then can decomposition of hydrogen peroxide;
(2) be added with Sodium Selenite and 3-mercaptoethanol in the prescription, the former is Wheat Protein also, and the latter can promote lymphocytic growth;
(3) two kinds of formulations are arranged, can be respectively applied for cell suspension culture and cell attachment and cultivate, particularly the latter is divided into two portions.A part is a substratum, contains purified cell Fibronectin; Another part is an extention, is purified short anchoring factor, can be used for overlaying at the bottom of the culturing bottle to promote cell attachment.
(4) concentration of various compositions is different with analogous products in the prescription: is 5-10mg/ml as bovine serum albumin in 1 times of serum free medium, and external like product majority only is 0.4mg/ml.Experiment confirm, the bovine serum albumin of 5-10mg/ml is promoting to be much better than 0.4mg/ml aspect the cell growth.
(5) the present invention is applicable to the growth of polytype tissue and cell: the present invention has been applied to the vitro culture as hematopoietic cell, lymphocyte, skin epithelial cells, tumour cell, stem cell, dendritic cell, monkey-kidney cells, immunologically competent cell.The applicant has also studied the apoptosis of tumour cell with the present invention and since got rid of serum existence itself can apoptosis-induced material interference, can reflect the apoptosis situation more truly.
Embodiment
Below in conjunction with embodiment the present invention is described in further detail.
Embodiment 1: the preparation of cell suspension culture serum free medium
(1), compound concentration is respectively the bovine serum albumin solution of 100mg/ml, the insulin solutions of 80 μ g/ml, the purifying human transferrin solution of 10 μ g/ml, the cholesterol solution of 200 μ g/ml and the hydrogen peroxide enzyme solution of 200 μ g/ml according to a conventional method, all is dissolved in Yi Sikefu improvement cutter than Ke Shi substratum;
(2), the preparation of sodium selenite solution: commercially available Sodium Selenite powder is taken by weighing 1.73mg, make it to be dissolved in the 10ml triply distilled water, Entkeimung, 4 ℃ of refrigerators preservations;
(3), the preparation of 3-mercaptoethanol solution: commercially available 3-mercaptoethanol 1ml is added in the 99ml triply distilled water, make it into 1% solution, Entkeimung, 4 ℃ of refrigerators preservations;
(4), measure the 1% 3-mercaptoethanol solution of 50.0ml bovine serum albumin solution, 50.0ml insulin solutions, 50.0ml purifying human transferrin solution, 50.0ml cholesterol solution, 50.0ml hydrogen peroxide enzyme solution, 0.05ml sodium selenite solution and 0.35ml respectively, above-mentioned seven kinds of solution are mixed, be the 500ml/ bottle with Yi Sikefu improvement cutter than the dilution of Ke Shi substratum again, get product.
Embodiment 2: the preparation of cell suspension culture serum free medium
(1), according to a conventional method prepare bovine serum albumin solution, the insulin solutions of 400 μ g/ml, the purifying human transferrin solution of 300 μ g/ml, the cholesterol solution of 600 μ g/ml and the hydrogen peroxide enzyme solution of 600 μ g/ml that final concentration is respectively 50mg/ml, all be dissolved in Yi Sikefu improvement cutter than Ke Shi substratum;
(2), the preparation of sodium selenite solution: commercially available Sodium Selenite powder is taken by weighing 1.73mg, make it to be dissolved in the 10ml triply distilled water, Entkeimung, 4 ℃ of refrigerators preservations;
(3), the preparation of 3-mercaptoethanol solution: commercially available 3-mercaptoethanol 1ml is added in the 99ml triply distilled water, make it into 1% solution, Entkeimung, 4 ℃ of refrigerators preservations;
(4), measure the 1% 3-mercaptoethanol solution of 50.0ml bovine serum albumin solution, 50.0ml insulin solutions, 50.0ml purifying human transferrin solution, 50.0ml cholesterol solution, 50.0ml hydrogen peroxide enzyme solution, 0.1ml sodium selenite solution and 0.35ml respectively, above-mentioned seven kinds of solution are mixed, be the 500m/ bottle with Yi Sikefu improvement cutter than the dilution of Ke Shi substratum again, get product.
Embodiment 3: cell attachment is cultivated the preparation of serum free medium
(1), compound concentration is respectively the bovine serum albumin solution of 50-100mg/ml, the insulin solutions of 80-400 μ g/ml, the purifying human transferrin solution of 10-300 μ g/ml, the cholesterol solution of 200-600 μ g/ml and the hydrogen peroxide enzyme solution of 200-600 μ g/ml according to a conventional method;
(2), the preparation of sodium selenite solution: commercially available Sodium Selenite powder is taken by weighing 1.73mg, makes it to be dissolved in the 10ml triply distilled water, Entkeimung, 4 ℃ of refrigerators are preserved, and make the sodium selenite solution that final concentration is 17.3 μ g/ml;
(3), the preparation of 3-mercaptoethanol solution: commercially available 3-mercaptoethanol 1ml is added in the 99ml triply distilled water, make it into 1% solution, Entkeimung, 4 ℃ of refrigerators preservations;
(4), the preparation of cell Fibronectin solution:
1., people's marrow fibroblast culture supernatant: obtain BMNC with the lymphocyte separation medium density gradient centrifugation, be incubated in the plastic culture bottle that is covered with 4% poly-lysine in advance with 1 * 106 cell/ml concentration, add 10% people AB serum and 10-6M hydrocortisone (final concentration), cultivated 5 days, form adherent individual layer, inhale and remove supernatant, change the cell suspension culture serum free medium and continue to cultivate 2 days, the results supernatant liquor is further purified;
2., 1 liter of people's marrow fibroblast culture supernatant being added gelatin-agarose that the 1ml bovine serum albumin handles hatched 24 hours for 4 ℃, separate gelatin-sepharose 4B with the centrifugation method in conjunction with the cell Fibronectin, with the can of 10ml pearl in the chromatography column of 1.5cm diameter; This post is at room temperature used the 0.15M NaCl of 4 times of post bed capacity, 10mM Tutofusin tris-hydrochloric acid (Tris-HCl), the pH7.0 washing is with damping fluid C[4M urea, 0.5M NaCl, 50mM hexahydroaniline propane sulfonic acid], the pH11.0 elution; Determine protein peak, the each several part that will contain the cell Fibronectin mixes, and with buffer A (0.15M NaCl, 1mM CaCl2,10mM hexahydroaniline propane sulfonic acid, readjustment pH to 11.0) dialysis, detects protein concn, makes into 0.125g/ml concentration, is stored in-70 ℃;
(5), measure 1% 3-mercaptoethanol solution and the 0.1ml Fibronectin solution of 50.0ml bovine serum albumin solution, 50.0ml insulin solutions, 50.0ml purifying human transferrin solution, 50.0ml cholesterol solution, 50.0ml superoxol, 0.05ml sodium selenite solution, 0.175ml respectively, above-mentioned eight kinds of solution are mixed, be the 500ml/ bottle with Yi Sikefu improvement cutter than the dilution of Ke Shi substratum again, promptly get cell attachment and cultivate serum free medium;
(6), the preparation of short anchoring factor:
1., people's marrow fibroblast culture supernatant: obtain BMNC with the lymphocyte separation medium density gradient centrifugation, be incubated in the plastic culture bottle that is covered with 4% poly-lysine in advance with 1 * 106 cell/ml concentration, add 10% people AB serum and 10-6M hydrocortisone (final concentration), cultivated 5 days, form adherent individual layer, inhale and remove supernatant, change the cell suspension culture serum free medium and continue to cultivate 2 days, the results supernatant liquor is further purified;
2., granulated glass sphere affinity chromatography: glass microballon with 0.6M NaHCO3 (pH8.0) washing, is adorned post (5cm * 50cm), use 0.6M NaHCO3 equilibrate overnight, flow velocity 100ml/ hour.People's marrow fibroblast culture supernatant is adjusted to pH8.0 with 0.1N NaOH, filter, with 100ml people's marrow fibroblast culture supernatant with sample on the 100ml/ speed at one hour rating, elution peak (behind 65kd and the 75kd) appears, with following damping fluid (all containing tolylsulfonyl fluorine (PMSF)) wash-out (100ml/ hour):
A.200ml?0.6M?NaHCO3·pH8.0
B.100ml?0.6M?NaHCO3-0.2M?Na2CO3,pH9.3-9.5
C.100ml H2OD.500ml 0.2M K2CO3, pH11.0 will mix with the each several part of 0.6M NaHCO3-0.2M Na2CO3 elution, carry out next step purifying;
3. concanavalin A-agarose column/diethylaminoethyl-(DEAE) chromatography:
(2.5cm * 20cm) (2.5cm * 3cm), the 2.5cm of can thereon * 16cm concanavalin A-agarose column layer uses the phosphoric acid buffer balance, 30ml/ hour to chromatography column then with diethylaminoethyl--agarose can bottom;
Urge each part (about 200ml) of anchoring factor with 0.6M NaHCO3-0.2M Na2CO3 from containing of glass bead column elution and be applied to concanavalin A/diethylaminoethyl-post, 30ml/ hour, press the laxative remedy elution:
1) 30ml 0.25M sodium phosphate (Na/pi), pH6.0,30ml/ hour;
2) 200ml 25mM Na/Pi, pH6.0,15ml/ hour;
3) 250ml contains the 25mM Na/Pi of 50mM seminose, pH6.0,30ml/ hour;
4) 30ml 25mM Na/Pi, pH6.0,30ml/ hour;
5) 60ml contains the 25mM Na/Pi of 100mM NaCl, pH6.0,30ml/ hour;
6) 100ml contains the 25mM Na/Pi of 0.5M Alpha-Methyl mannoside and 1M NaCl, pH6.0,30ml/ hour;
7) 100ml contains the 0.15M NaCl 20mM Tutofusin tris of (containing 1mM MgCl2,1mM CaCl2 and 1mM MnCl2), and pH7.3 contains the elution peak 25mM Na/Pi elution that contains 100mM NaCl of the material of PAF;
4. heparin-agarose column chromatography:
Heparin-agarose chromatography column (the dress of 0.7cm * 10cm) post, and with the 25mMNa/Pi that contains 100mM NaCl, pH6.0 balance (15ml/ hour), the part difference (not mixing) that contains short anchoring factor of concanavalin A/diethylaminoethyl-purifying goes up sample to the heparin-agarose post, 7.5ml/ hour, by the laxative remedy elution, promptly get and urge anchoring factor:
1) 20ml contains the 25mM Na/Pi of 100mM NaCl, pH6.0 (15ml/ hour);
2) 20ml contains among the 50mM Na/Pi of 100mM NaCl, pH7.0 (4ml/ hour);
3) 20ml contains among the 50mM Na/Pi of 1M NaCl, pH7.4 (15ml/ hour);
At the bottom of overlaying the culturing bottle bottle with short anchoring factor, cultivate with cell attachment cultivation serum free medium mixed culture cell injection culturing bottle again (7), earlier.
Embodiment 4: cell attachment is cultivated the preparation of serum free medium
The preparation of sodium selenite solution among the embodiment 4, the preparation of 3-mercaptoethanol solution, the preparation of cell Fibronectin solution is identical with embodiment 3 with the preparation of short anchoring factor, and difference is:
(8), compound concentration is respectively the bovine serum albumin solution of 50mg/ml, the insulin solutions of 400 μ g/ml, the purifying human transferrin solution of 300 μ g/ml, the cholesterol solution of 600 μ g/ml and the hydrogen peroxide enzyme solution of 600 μ g/ml according to a conventional method, all is dissolved in Yi Sikefu improvement cutter than Ke Shi substratum.0.1ml the 1% 3-mercaptoethanol solution of sodium selenite solution, 0.35ml, 0.2ml Fibronectin solution, above-mentioned eight kinds of solution are mixed, be the 500ml/ bottle with Yi Sikefu improvement cutter than the dilution of Ke Shi substratum again, promptly get cell attachment and cultivate serum free medium.