BRAIN-LOCALIZING CELLS AND USES THEREOF
It was discovered that cells expressing brain-localizing polypeptides on the cell surface can pass through the blood-brain barrier and therefore have the activity of translocating to the brain. By introducing desired substances into such brain-localizing cells, the substances can also be translocated to the brain. For example, by intravenously administering brain-localizing cells into which pharmaceutical agents having therapeutic effects on brain diseases have been introduced, such agents can be efficiently delivered into the brain and the brain diseases can be effectively treated.
1 . A brain-localizing cell that expresses a polypeptide having brain-localizing activity on the cell surface.
2 . The brain-localizing cell of claim 1 , wherein the polypeptide having brain-localizing activity comprises the following amino acid motif sequence:
X 1 -(R or K)-X 3 -X4; or
X 4 -X 3 -(R or K)-X 1 ,
wherein X 1 denotes S, T, N, P, V, or L; X 3 denotes an arbitrary amino acid; and X 4 denotes G, S, T, C, N, L, Q, or Y.
3 . The brain-localizing cell of claim 2 , wherein the amino acid motif sequence is the following sequence:
X 1 -(R or K)-X 3 -X 4 ; or
X 4 -X 3 -(R or K)-X 1 ,
wherein X 1 denotes S, T, N, P, or V; X 3 denotes an arbitrary amino acid; and X 4 denotes an uncharged polar amino acid (G, S, T, C, N, Q, or Y).
4 . The brain-localizing cell of claim 2 , wherein the amino acid motif sequence is the following sequence:
X 1 -(R or K)-X 3 -X 4 ; or
X 4 -X 3 -(R or K)-X 1 ,
wherein X 1 denotes S, T, P, or L; X 3 denotes an arbitrary amino acid; and X 4 denotes S, T, C, L, or Q.
5 . The brain-localizing cell of claim 1 , wherein the polypeptide having brain-localizing activity comprises any one of the amino acid sequences of SEQ ID NOs: 1 to 12.
6 . The brain-localizing cell of claim 1 , wherein the length of the polypeptide having brain-localizing activity is 9 amino acids or shorter.
7 . The brain-localizing cell of claim 1 , wherein the cell has the ability to permeate the blood-brain barrier.
8 . The brain-localizing cell of claim 1 , wherein the cell is a yeast cell.
9 . A carrier for delivery to the brain which comprises as an active ingredient the brain-localizing cell of claim 1 .
10 . A brain-localizing pharmaceutical agent comprising the carrier for delivery to the brain of claim 9 which comprises a biologically active substance.
11 . The brain-localizing pharmaceutical agent of claim 10 , wherein the biologically active substance has a therapeutic effect on a brain disease.
12 . A method for producing a brain-localizing cell, which comprises the step of expressing a polypeptide having brain-localizing activity on the cell surface.
13 . The method of claim 12 , which comprises the step of introducing a nucleic acid encoding the polypeptide having brain-localizing activity into the cell.
14 . A method for producing a brain-localizing pharmaceutical agent, wherein the method comprises the step of introducing a biologically active substance into the brain-localizing cell of claim 1 .
15 . A kit for producing a brain-localizing cell, wherein the kit comprises a cell and a nucleic acid encoding a polypeptide having brain-localizing activity as components.
16 . A method for translocating a desired substance to the brain of a non-human animal, wherein the method comprises the following steps (a) and (b):
(a) introducing a desired substance into the brain-localizing cell of claim 1 to produce a brain-localizing cell comprising the substance; and
(b) administering the brain-localizing cell produced in step (a) to the body of a non-human animal.
17 . A method for treating a brain disease, wherein the method comprises the step of administering the brain-localizing cell of claim 1 to an individual.