Abstract: The invention relates to: a composition for culturing natural killer cells, comprising, as an active ingredient, a fusion protein comprising an IL-2 protein and a CD80 protein; and a method for preparing natural killer cells by using same. Particularly, a composition for culturing natural killer cells, comprising, as an active ingredient, a fusion protein comprising IL-2 or a variant thereof and CD80 or a fragment thereof, of the present invention; promotes the proliferation of natural killer cells, induces the expression of CD16 and NKp46, and increases the expression and secretion of granzyme B and perforin, thereby being effectively usable in the preparation of natural killer cells having an excellent anticancer immune function.

Abstract: The present invention relates to a block copolymer, comprising a hydrophilic first block, a hydrophobic second block, and a functional group capable of specifically binding to thiol.

Abstract: Disclosed are a composition for NK (natural killer) cell cryopreservation and an NK cell cryopreservation formulation. This composition can exhibit cell surface marker expression and NK cell degranulation ability at at least the same level as formulations using commercially available cryopreservation media, even in low-concentration DMSO (dimethyl sulfoxide) not including HEPES (hydroxyethyl piperazine ethane sulfonic acid) or HES (hydroxyethyl starch), and can show a high cell yield and vastly superior ability of NK cells to kill cancer cells. Since a conventional cryoprotectant, showing side effects due to nonspecific toxicity, is not included or is comprised at a low concentration and is replaced with a nontoxic and biocompatible cryoprotectant, the composition can be administered to a patient immediately after thawing without additional culture or replacement of the solution with an injectable solution, and is thus usable for a pharmaceutical formulation.

Abstract: The present invention relates to a method for effectively proliferating regulatory T cells, by which, particularly, in the presence of a fusion protein dimer comprising IL-2 protein or a variant thereof and CD80 protein or a fragment thereof, CD4+, CD25+, and CD127? T cells can be effectively proliferated. In particular, when combined with a predetermined cell culture medium, regulatory T cells such as CD4+, CD25+, and CD127? can be effectively and specifically proliferated. In addition, when the method is used, it has been confirmed that the survival rate of regulatory T cells is remarkably increased as compared to a conventionally used culture method using IL-2, and a significant increase in the yield of Foxp3+ regulatory T cells has been confirmed. Thus, such a proliferation method can be used in the field of cell therapeutic agents using regulatory T cells.