945 results about "In vitro experiment" patented technology

The invention discloses a method for promoting in-vitro and in-vivo degradation and cell extension adherence of alginate-based 3D printed bioink. The method comprises the following steps: step 1, adopting alginate as an extracellular matrix main body skeleton and constructing celliferous 3D bio-printed bioink; step 2, mixing alginate lyase with alginate-based bioink; step 3, adding cell suspensioninto the obtained bioink, choosing print parameters and printing out a 3D printing block through a 3D bio-printer; step 4, regulating and controlling in-vitro and after-transplantation-in-vivo degradation time and cell extension adherence degree of the 3D printing block through adjusting the concentration of the alginate lyase according to actual demands. The method disclosed by the invention canpromote the degradation and cell extension adherence of the bioink with the alginate as the skeleton under in-vivo and in-vitro environments, and enables the alginate 3D printed bioink to be adaptedto more in-vivo and in-vitro experiments and be better applied to soft tissue repairing and transplantation.

The invention discloses a preparation method of exosome and a stem cell proliferation reagent containing the exosome. The preparation method of the exosome comprises the steps that 1, a culture mediumwithout exosome serum is added bone marrow mesenchymal stem cells to dilute the bone marrow mesenchymal stem cells into a cell suspension, the cell suspension is inoculated into a cell culture bottleto be cultured, supernate obtained after culture is collected, and the exosome is extracted; 2, cell fragments, dead cells and impurities in the supernate are removed; the supernate is removed, thena phosphate buffer salt solution (PBS) is added to dissolve and collect exosome precipitate, the exosome precipitate is filtered through a sterile filter membrane, and the obtained exosome precipitateis packaged in a sterile centrifugal tube and stored for later use. According to the method, in-vitro experiments prove that the proliferation activity and related functions of the mesenchymal stem cells can be remarkably promoted by co-culturing the exosome secreted by the early-generation bone marrow mesenchymal stem cells and human umbilical cord mesenchymal stem cells, and the method is an effective strategy for potentially improving the function of cells in a large-scale cell culture process.