Abstract: A novel means for safely and efficiently introducing a target substance such as nucleic acid, protein, or the like into immune cells such as T cell and the like is provided by the present invention. Thus, a system for delivering a target substance into an immune cell, including ultrafine bubble water or ultrafine bubble aqueous solution containing ultrafine bubbles with an average diameter of not more than 200 nm and not containing phospholipid, and an ultrasound generator in combination; a method for increasing the delivery of a nucleic acid or a protein into an immune cell by using the ultrafine bubble water, etc. and ultrasound; and the like are provided.

Abstract: The present invention provides hyaluronic acid derivatives into which a certain cationic group and a certain hydrophobic group are introduced, the hyaluronic acid derivatives including one or more repeating units represented by the formula (Ia) and one or more repeating units represented by the formula (Ib).

Abstract: The present invention provides a vaccine formulation for use in the prevention and/or treatment of a cancer, comprising a complex of a hyaluronic acid derivative having an introduced hydrophobic group, and an antigen.

Abstract: Provided is a method for easily and efficiently producing encapsulated substance vesicles wherein a substance is encapsulated in the cavity of vesicles obtained by polymer self-assembly. Empty vesicles that have membranes comprising a first polymer that is a block copolymer with uncharged hydrophilic segments and a first kind of charged segments and a second polymer with a second kind of charged segments that carry a charge that is the opposite of said first kind of charged segments as well as spaces that are enclosed by said membranes are mixed in an aqueous medium with the substance that is to be encapsulated in the spaces.

Abstract: The present invention provides hyaluronic acid derivatives into which a certain cationic group and a certain hydrophobic group are introduced, the hyaluronic acid derivatives including one or more repeating units represented by the formula (Ia) and one or more repeating units represented by the formula (Ib).

Abstract: Provided is a method for easily and efficiently producing encapsulated substance vesicles wherein a substance is encapsulated in the cavity of vesicles obtained by polymer self-assembly. Empty vesicles that have membranes comprising a first polymer that is a block copolymer with uncharged hydrophilic segments and a first kind of charged segments and a second polymer with a second kind of charged segments that carry a charge that is the opposite of said first kind of charged segments as well as spaces that are enclosed by said membranes are mixed in an aqueous medium with the substance that is to be encapsulated in the spaces.

Abstract: Provided is a method for easily and efficiently producing encapsulated substance vesicles wherein a substance is encapsulated in the cavity of vesicles obtained by polymer self-assembly. Empty vesicles that have membranes comprising a first polymer that is a block copolymer with uncharged hydrophilic segments and a first kind of charged segments and a second polymer with a second kind of charged segments that carry a charge that is the opposite of said first kind of charged segments as well as spaces that are enclosed by said membranes are mixed in an aqueous medium with the substance that is to be encapsulated in the spaces.

Abstract: Provided is a method for easily and efficiently producing encapsulated substance vesicles wherein a substance is encapsulated in the cavity of vesicles obtained by polymer self-assembly. Empty vesicles that have membranes comprising a first polymer that is a block copolymer with uncharged hydrophilic segments and a first kind of charged segments and a second polymer with a second kind of charged segments that carry a charge that is the opposite of said first kind of charged segments as well as spaces that are enclosed by said membranes are mixed in an aqueous medium with the substance that is to be encapsulated in the spaces.