Method for preparing cellular spheroid and method for producing extracellular vesicles by using cellular spheroid prepared by such method

A method of producing an extracellular vesicle using a cellular spheroid, the method comprising:

• preparing a first composition comprising cells and a heat-sensitive hydrogel dissolved in an ionic solution;
• dispensing the first composition drop by drop into a second hydrogel;
• forming a core-shell structure by causing a reaction between the second hydrogel and the ionic solution in the first composition along an outer surface of a droplet of the first composition injected into the second hydrogel to form a cross-linked hydrogel shell only on the outer surface of the droplet of the first composition;
• changing a temperature so that the heat-sensitive hydrogel in the cross-linked hydrogel shell undergoes a phase change from a gel phase to a liquid phase;
• forming a cellular spheroid by allowing the inside of the cross-linked hydrogel shell to be changed into the liquid phase and allowing the cells to precipitate and aggregate to form the cellular spheroid;
• recovering the cellular spheroid from a hollow structure produced by degradation of the cross-linked hydrogel shell without an enzyme;
• and
• culturing the cellular spheroid to obtain an extracellular vesicle,
• wherein a concentration of ions in the ionic solution is in a range of 10 mM to 700 mM,
• wherein the recovering of the cellular spheroid is performed by a method using any one or more selected from among heat, an electric field, and a magnetic field, and
• wherein the heat-sensitive hydrogel comprises one or more selected from the group consisting of Pluronic F127 and poly(N-isopropylacrylamide).