Abstract: Provided is a peptide represented by the following formula (I): R1-IWLTALX5FLGX6X1AAX7X2X3AX8QX4LSX9L-R2?(I) wherein X1, X2, X3, X4, X5, X6, X7, X8, X9, R1, and R2 are as defined in the specification.

Abstract: Provided is a peptide represented by the following formula (I): R1-IWLTALX5FLGX6X1AAX7X2X3AX8QX4LSX9L-R2?(I) wherein X1, X2, X3, X4, X5, X6, X7, X8, X9, R1, and R2 are as defined in the specification.

Abstract: A lipid membrane structure for delivering a substance into a nucleus of a cell, wherein lipid membrane is modified with (a) a polypeptide comprising the amino acid sequence of SEQ ID NO: 1, and/or (b) a polypeptide consisting of an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 1, but including deletion and/or substitution and/or insertion of one or several amino acid residues, and having an activity of promoting migration of the lipid membrane structure into a nucleus of a cell, which can efficiently deliver a nucleic acid into a nucleus of an immunocyte such as dendritic cell.

Abstract: A lipid membrane structure for delivering a substance into a nucleus of a cell, wherein lipid membrane is modified with (a) a polypeptide comprising the amino acid sequence of SEQ ID NO: 1, and/or (b) a polypeptide consisting of an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 1, but including deletion and/or substitution and/or insertion of one or several amino acid residues, and having an activity of promoting migration of the lipid membrane structure into a nucleus of a cell, which can efficiently deliver a nucleic acid into a nucleus of an immunocyte such as dendritic cell.

Abstract: With the aim of providing a liposome, having a hydrophilic polymer introduced into the outer surface of the liposome membrane, which is a liposome capable of allowing the liposome-entrapped substance to escape from the endosome and be released into the cytoplasm, a liposome membrane component bound to the peptide shown by (a) or (b) below and a liposome membrane component bound to one end of a hydrophilic polymer the other end of which is bound to the peptide shown by (a) or (b) below are included in the liposome: (a) a peptide comprising the amino acid sequence of SEQ ID NO:1; (b) a peptide comprising the amino acid sequence of SEQ ID NO:1 with 1 or more amino acids deleted, replaced or added therein, and capable of fusing lipid membranes with one another under acidic conditions.

Abstract: With the object of providing a liposome having cellular and nuclear entry ability, to achieve this object, a liposome is provided having on its surface a peptide comprising multiple consecutive arginine residues, and specifically a liposome is provided wherein the peptide is modified with a hydrophobic group or hydrophobic compound and the hydrophobic group or hydrophobic compound is inserted into a lipid bilayer so that the peptide is exposed on the surface of the bilayer.

Abstract: A lipid membrane structure for delivering a substance into a nucleus of a cell, wherein lipid membrane is modified with (a) a polypeptide comprising the amino acid sequence of SEQ ID NO: 1, and/or (b) a polypeptide consisting of an amino acid sequence comprising the amino acid sequence of SEQ ID NO: 1, but including deletion and/or substitution and/or insertion of one or several amino acid residues, and having an activity of promoting migration of the lipid membrane structure into a nucleus of a cell, which can efficiently deliver a nucleic acid into a nucleus of an immunocyte such as dendritic cell.

Abstract: It is intended to provide a positively charged liposome, particularly having a polyarginine peptide on a surface thereof, which is capable of increasing the resistance to a negatively charged biological component such as a protein in the blood and maintaining a high ability to deliver a substance even in the blood. An agent for enhancing the resistance of liposome against biological component comprising a peptide having at least one of the following characteristics (a) and (b) as an active ingredient: (a) A peptide comprising an amino acid sequence represented by SEQ ID No: 1 or 2; and (b) A peptide comprising an amino acid sequence represented by SEQ ID No: 1 or 2, in which one or more amino acids are deleted, substituted or added, and having an activity for promoting lipid membrane fusion under acidic condition.

Abstract: Disclosed is a non-viral vector capable of delivering a given substance into the nucleus of a target cell effectively even when the target cells is a undividable cell such as a dendritic cell. A bilamellar liposome having a first lipid membrane and a second lipid membrane successively from the outside, the first lipid membrane having a membrane-fusing ability and the second lipid membrane having on its surface a nuclear transport peptide.

Abstract: With the aim of providing a liposome, having a hydrophilic polymer introduced into the outer surface of the liposome membrane, which is a liposome capable of allowing the liposome-entrapped substance to escape from the endosome and be released into the cytoplasm, a liposome membrane component bound to the peptide shown by (a) or (b) below and a liposome membrane component bound to one end of a hydrophilic polymer the other end of which is bound to the peptide shown by (a) or (b) below are included in the liposome: (a) a peptide comprising the amino acid sequence of SEQ ID NO:1; (b) a peptide comprising the amino acid sequence of SEQ ID NO:1 with 1 or more amino acids deleted, replaced or added therein, and capable of fusing lipid membranes with one another under acidic conditions.

Abstract: With the object of providing a liposome having cellular and nuclear entry ability, to achieve this object, a liposome is provided having on its surface a peptide comprising multiple consecutive arginine residues, and specifically a liposome is provided wherein the peptide is modified with a hydrophobic group or hydrophobic compound and the hydrophobic group or hydrophobic compound is inserted into a lipid bilayer so that the peptide is exposed on the surface of the bilayer.

Abstract: The present invention provides an immunoglobulin preparation comprising an immunoglobulin-hydrophilic peptide complex in which an immunoglobulin and a hydrophilic peptide are linked optionally via a divalent group, and a pharmacologically acceptable carrier. The immunoglobulin preparation has cell permeability, or in other words, it can penetrate through a cell membrane and attain inside.