This document provides methods and materials relating to platelet lysates. For example, methods and materials for using platelet lysate compositions to grow adult stem cells, to differentiate adult stem cells, to grow primary cell cultures, to grow tumor stem cells, and to identify effective growth factors are provided.

Provided is a method for rapidly separating and extracting human umbilical cord mesenchymal stem cells (hUC-MSC). The method comprises the following steps: taking freshly collected healthy neonatal umbilical cord tissue, and after removing the blood vessels, bluntly dissecting the Wharton's jelly, mechanically pulverising same, and treating with erythrocyte lysate for 3 minutes; carrying out type IV collagenase digestion, and after sieving through a 100-200 mesh sieve, carrying out suspension culture in a serum-free culture medium, replacing the liquid every 3-5 days; taking the supernatant to detect cell contamination, and waiting for the adherence rate to reach 30-70%; carrying out trypsin digestion, collecting the cells by centrifugation, and carrying out passage amplification, until the rate of confluence of the cells reaches over 90%; collecting the cells for cryopreservation, and detecting the biological characteristics of the hUC-MSC.

Provided is a serum-free culture medium, the ingredients of the culture medium comprising 0.05-0.2 parts by volume of -mercaptoethanol, 0.5-2 parts by volume of non-essential amino acid aqueous solution, 4-6 parts by volume of human mesenchymal stem cell culture supernatant concentrate, and 90-95 parts by volume of a-MEM/DMEM-F12 and recombinant human alkaline fibroblast growth factor of a final concentration of 5-5 ng/ml. The present culture medium is used for carrying out stem cell culture.

The present disclosure provides compositions, kits, and methods for promoting in vitro maturation of cells. The present disclosure also provides methods of screening compounds that are suitable for promoting in vitro maturation of cells.

An exosome production promoter that promotes production of exosomes from adipose-derived mesenchymal stem cells is provided. The exosome production promoter promotes production of exosomes from adipose-derived mesenchymal stem cells cultured in a serum-free medium and contains EGF. It is preferable that the exosome production promoter further contains IL-1? and trehalose. It is desirable that the exosome production promoter does not contain SCGF. It is preferable that the adipose-derived mesenchymal stem cells are cultured using a nonwoven fabric sheet as a scaffold. The exosomes mass-produced by the technique according to the present invention can be used, for example, for cosmetic plastic procedures or the like.

A method of expanding and maintaining human embryonic stem cells (ESCs) in an undifferentiated state by culturing the ESCs in a suspension culture under culturing conditions devoid of substrate adherence is provided. Also provided are a method of deriving ESC lines in the suspension culture and methods of generating lineage-specific cells from ESCs which were expanded in the suspension culture of the present invention.

The disclosure relates to methods for producing mesodermal lineage cells, cardiac lineage cells, hematopoietic lineage cells, retinal lineage cells, and combinations thereof. In some aspects, the disclosure relates to methods of producing mixed tissue organoids comprising retinal lineage cells and cardiac lineage cells. When interaction of WDR5 protein at the binding pocket/interaction surface with RBBP5/MYC/KANSL2 is disrupted in the embryonic stem cell for a set period of time after differentiation of the embryonic stem cell has begun, and the disruption of that interaction is subsequently removed, differentiation of the embryonic stem cell to a mesodermal lineage cell is obtained. Such mesodermal lineage cells may, in some methods of the disclosure, be subsequently differentiated into cardiac lineage cells and hematopoietic lineage cells. The disclosure also relates to method for producing mixed lineage organoids, comprising retinal and mesodermal, including cardiac, lineage cells in a single organoid. The disclosure also relates to cells and organoids obtained by the methods, uses of the cells and organoids, and kits comprising the cells and/or reagents for producing them.

The present invention is related to a medium additive composition comprising peroxidasin for serum-free cell culture, and a method of performing serum-free culture of cells by using the same.

The present invention relates to methods and compositions for modulating glycosylation of recombinant proteins expressed by mammalian host cells during the cell culture process. Also disclosed are methods of culturing a host cell expressing a recombinant protein in a cell culture medium comprising a disaccharide or a trisaccharide, while keeping the osmolality constant.

It is an object of the present invention to provide a cell culture medium capable of enhancing cell growth efficiency without using feeder cells, in particular which does not comprise serum. The present invention provides a cell culture medium which comprises growth arrest-specific 6 (GAS6) and does not comprise serum.