BRAIN ORGANOID AND USE THEREOF
According to a production method for a brain organoid, comprising a step 1 of carrying out suspension culture of human pluripotent stem cells having a mutation in at least one or more base sequences in an exon selected from the group consisting of an exon 9, an exon 10, an exon 11, an exon 12, and an exon 13 of a microtubule-associated protein tau (MAPT) gene, and having a mutation in at least one or more base sequences in an intron 10 of the MAPT gene, it is possible to produce a brain organoid having a phosphorylated 3-repeat tau protein and a phosphorylated 4-repeat tau protein.
1 . A production method for a brain organoid, comprising:
(1) suspension culturing of human pluripotent stem cells having a mutation in at least one or more base sequences in an exon selected from the group consisting of an exon 9, an exon 10, an exon 11, an exon 12, and an exon 13 of a microtubule-associated protein tau (MAPT) gene, and having a mutation in at least one or more base sequences in an intron 10 of the MAPT gene.
2 . The production method for a brain organoid according to claim 1 ,
wherein the base sequence mutation in the exon is mutations in two or more base sequences.
3 . The production method for a brain organoid according to claim 2 ,
wherein the base sequence mutation in the exon includes mutations in base sequences in the exon 10, encoding amino acid mutations of N279K and P301S.
4 . The production method for a brain organoid according to claim 1 ,
wherein the base sequence mutation in the intron 10 includes a base sequence mutation of E10+16.
5 . The production method for a brain organoid according to claim 1 ,
wherein the base sequence mutation in the exon is mutations in base sequences in the exon 10, encoding amino acid mutations of N279K and P301S, and
the base sequence mutation in the intron 10 is a base sequence mutation of E10+16.
6 . The production method for a brain organoid according to claim 1 ,
wherein the (1) suspension culturing is carried out in a culture medium 1 containing an inhibitor of a bone morphogenetic protein (BMP) signal transduction pathway and an inhibitor of a transforming factor β (transforming growth factor β, TGF-β) family signal transduction pathway.
7 . The production method for a brain organoid according to claim 1 , further comprising:
(2) culturing a culture preparation formed by the (1) suspension culturing in a culture medium 2 containing an enhancing agent of Wnt signaling and an extracellular matrix; and
(3) culturing a culture preparation formed by the (2) culturing in a culture medium 3 containing no extracellular matrix.
8 . The production method for a brain organoid according to claim 7 , further comprising:
(4) dispersing the brain organoid produced by the production method for a brain organoid according to claim 1 to obtain a dispersion; and
(5) culturing the dispersion in the presence of a tau protein aggregate.
9 . The production method for a brain organoid according to claim 8 ,
wherein the (5) culturing is carried out in the presence of 0.0005 ng to 0.4 ng of the tau protein aggregate per one cell contained in the dispersion.
10 . The production method for a brain organoid according to claim 8 ,
wherein the tau protein aggregate includes an aggregate of a recombinant tau protein.
11 . The production method for a brain organoid according to claim 10 ,
wherein the recombinant tau protein is encoded by a MAPT gene having a base sequence mutation in an exon 10.
12 . The production method for a brain organoid according to claim 8 ,
wherein the (5) culturing is carried out in the presence of a phosphorylation-accelerating reagent.
13 . A brain organoid comprising:
a misfolded 3-repeat tau protein; and
a misfolded 4-repeat tau protein.
14 . The brain organoid according to claim 13 ,
wherein the misfolded 3-repeat tau protein includes a phosphorylated 3-repeat tau protein, and
the misfolded 4-repeat tau protein includes a phosphorylated 4-repeat tau protein.
15 . The brain organoid according to claim 14 ,
wherein a detection signal of the phosphorylated 4-repeat tau protein shown by a Western blot method is 0.5 or more with respect to a detection signal of 1 of the phosphorylated 3-repeat tau protein.
16 . The brain organoid according to claim 14 , wherein the phosphorylated 4-repeat tau protein is a phosphorylated 0N4R tau protein.
17 . The brain organoid according to claim 14 ,
wherein the phosphorylated 3-repeat tau protein is a phosphorylated 0N3R tau protein.
18 . A drug efficacy evaluation method, comprising:
bringing the brain organoid according to claim 13 into contact with a test substance; and
examining an effect of the test substance on the brain organoid.
19 . The drug efficacy evaluation method according to claim 18 , further comprising transplanting the brain organoid according to claim 13 into a brain of a mammal before the bringing the brain organoid into contact with the test substance.