153results about How to "Stable passage" patented technology

The invention discloses a small-molecular compound combination for differentiated cell reprogramming, and a reagent kit and an application of the small-molecular compound combination. The small-molecular compound combination includes the following components: a TGF-beta inhibitor, a WNT / beta-catenin agonist, a cAMP agonist and a PKC inhibitor; furthermore, the small-molecular compound combinationalso includes at least one of an RAR agonist, a DNMT inhibitor, an HMT inhibitor, a histone demethylase inhibitor, ascorbic acid, a JNK inhibitor, an ROCK inhibitor and a lysine deacetylase inhibitor.Differentiated cells can be reprogrammed into mesenchymal stem cells by phased induction with the small-molecular compound combination, all steps can be subjected to precise quality control, and standardization operation and large-scale production are convenient. The method provided by the invention has wide donor sources, a patient himself can be used as a donor, and the mesenchymal stem cells needed for basic research, clinical treatment or tissue engineering production can be obtained in relatively short time.

The invention provides a hair follicle stem cell separation culture method. The method utilizes an organ culture method, adopts the William's E complete medium to culture the hair follicle, separate and purify to get hair follicle stem cells. The method only uses very small skin materials, the rat whisker follicle is separated with a stereoscope through a micro separation method, then the whole whisker follicle is cultured, the hair follicle stem cells grow out from the projection part and form clone, so the cell clone forming efficiency is high, the purification is easy, long-term passage can be realized, the characteristics of the hair follicle stem cells are kept unchanged, and only one whisker follicle can obtain enough hair follicle stem cells for long-term use.

The invention provides a high-productive strain Bacillus subtillis CGMCC No.2108 of poly-Gamma -glutamic-acid; the invention also provides a culture method and an applicable culture medium of the strain. The poly-Gamma -glutamic-acid provided by the invention is has the simple requirement of strain nutrient, stable passage, maximum output of 34.1g per liter, simple and practical culture method, wide culture medium raw material source and low cost, thus effectively reducing the production cost and being suitable for large-scale industrial production.

The invention relates to a drug-resistant cell strain of human bile duct cancer. The drug-resistant cell strain has a collection number of CCTCC NO:C 201441. A human bile duct cancer RBE cell strain is selected as a parent cell and is added into 5-FU for culture, the action concentration is gradually increased according to a concentration sequence of 25, 50, 75 and 100mu g / ml, and the drug-resistant cell strain of human bile duct cancer is established. The drug-resistant cell strain RBE / 5-FU of the human bile duct cancer can provide a drug-resistant tumor cell model for researching a drug-resistant tumor mechanism, analyzing the sensitivity of chemotherapeutics, screening and evaluating the chemotherapeutics, developing drug-resistant tumor reversing drugs and researching more effective tumor treatment methods.

The invention discloses a method for constructing a monascus strain capable of achieving high yield of acid protease. The method is characterized by firstly amplifying an Asp fragment of an acid protease gene in monascus from a monascus genome, then connecting the Asp fragment obtained through amplification to an empty vector to construct a recombinant expression vector of acid protease in monascus, transforming the recombinant expression vector of acid protease in monascus into agrobacterium tumefaciens to obtain recombinant agrobacterium tumefaciens and then guiding the recombinant agrobacterium tumefaciens into monascus by utilizing an agrobacterium tumefaciens-mediated method, thus obtaining the monascus strain capable of achieving high yield of acid protease. The monascus transformant strain capable of achieving high yield of acid protease, which is obtained by a gene recombination method, has the characteristics of high-efficiency expression, accuracy in processing and genetic stability of the transformant and can achieve passage stability under non-selective pressure. The expression quantity of the acid protease gene in the monascus strain capable of achieving high yield of acid protease is 3.30 times the expression quantities of wild type genes, so that high yield of acid protease can be achieved.