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US-20260124323-A1 - ADENO-ASSOCIATED VIRUS VARIANT AND USE THEREOF

US20260124323A1US 20260124323 A1US20260124323 A1US 20260124323A1US-20260124323-A1

Abstract

Disclosed are adeno-associated virus (AAV) capsid protein variants that have improved infectivity and transduction efficiency for target cells, and uses thereof. Specifically, the disclosure relates to AAV2 variant capsid proteins selected by directed evolution for gene delivery to retinal cells, recombinant AAV vectors comprising the same, and uses thereof as gene delivery vehicles to retinal cells.

Inventors

  • Jae-Hyung Jang
  • Junwon Lee
  • Yoojin Kim
  • Han JEONG

Assignees

  • UIF (UNIVERSITY INDUSTRY FOUNDATION), YONSEI UNIVERSITY

Dates

Publication Date
20260507
Application Date
20251031
Priority Date
20241101

Claims (16)

  1. 1 . An adeno-associated virus 2 (AAV2) variant capsid protein comprising point mutations H38P, 1698V, N705A, V708A, T716N, V719L, S721T, and N734P at positions corresponding to positions 38, 698, 705, 708, 716, 719, 721, and 734 of wild-type AAV2 capsid protein of SEQ ID NO: 1.
  2. 2 . The AAV2 variant capsid protein of claim 1 , wherein the AAV2 variant capsid protein comprises the amino acid sequence of SEQ ID NO: 2 or an amino acid sequence having at least 95% sequence identity thereto.
  3. 3 . The AAV2 variant capsid protein of claim 1 , wherein the AAV2 variant capsid protein consists of the amino acid sequence of SEQ ID NO: 2 or an amino acid sequence having at least 95% sequence identity thereto.
  4. 4 . The AAV2 variant capsid protein of claim 1 , wherein the AAV2 variant capsid protein confers increased infectivity to retinal cells compared to a wild-type AAV2 capsid protein.
  5. 5 . The AAV2 variant capsid protein of claim 4 , wherein the retinal cells are selected from the group consisting of retinal ganglion cells, bipolar cells, photoreceptors, Muller glial cells, horizontal cells, amacrine cells, astrocytes, microglial cells, retinal vascular cells, and retinal pigment epithelial cells.
  6. 6 . An isolated nucleic acid encoding the AAV2 variant capsid protein of claim 1 .
  7. 7 . A host cell comprising an isolated nucleic acid encoding the AAV2 variant capsid protein of claim 1 .
  8. 8 . A recombinant AAV vector comprising: an AAV2 variant capsid protein comprising point mutations H38P, 1698V, N705A, V708A, T716N, V719L, S721T, and N734P at positions corresponding to positions 38, 698, 705, 708, 716, 719, 721, and 734 of wild-type AAV2 capsid protein of SEQ ID NO: 1, and a heterologous nucleic acid comprising a sequence encoding a target product.
  9. 9 . The recombinant AAV vector of claim 8 , wherein the recombinant AAV vector confers increased transduction of retinal cells compared to an AAV vector comprising a wild-type AAV2 capsid protein.
  10. 10 . The recombinant AAV vector of claim 8 , wherein the target product is a polypeptide or nucleic acid.
  11. 11 . A method for treating an ocular disease in a subject in need thereof, comprising administering the recombinant AAV vector of claim 8 .
  12. 12 . The method of claim 11 , wherein the ocular disease is selected from the group consisting of retinal, vitreous, and choroidal disorders, retinal vascular diseases, macular diseases, hereditary retinal diseases, hereditary vitreous diseases, hereditary choroidal diseases, intraocular inflammatory diseases, intraocular tumors, glaucoma, and optic neuropathies.
  13. 13 . The method of claim 11 , wherein the ocular disease is selected from the group consisting of macular degeneration, diabetic retinopathy, retinal vascular occlusion, macular telangiectasia, retinopathy of prematurity, myopic degeneration, retinitis pigmentosa, Leber congenital amaurosis, Best disease, Stargardt disease, congenital stationary night blindness, X-linked retinoschisis, Bietti crystalline dystrophy, total achromatopsia, cone dystrophy, cone-rod dystrophy, maculopathy, Usher syndrome, Bardet-Biedl syndrome, syndromic retinitis pigmentosa, pan choroidal atrophy, central serous chorioretinopathy (CSR), gyrate atrophy of choroid and retina, glaucoma, optic neuropathy, uveitis, uveal melanoma, intraocular lymphoma, retinoblastoma, retinal detachment, and retinal injury.
  14. 14 . The method of claim 11 , wherein the recombinant AAV vector is administered via intravitreal injection, subretinal injection, or suprachoroidal injection.
  15. 15 . An in vitro method for delivering a heterologous nucleic acid to retinal cells, comprising contacting the recombinant AAV vector of claim 8 with the retinal cells.
  16. 16 . The method of claim 15 , wherein the retinal cells are selected from the group consisting of retinal ganglion cells, bipolar cells, photoreceptors, Muller glial cells, horizontal cells, amacrine cells, astrocytes, microglial cells, retinal vascular cells, and retinal pigment epithelial cells.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application is based on and claims priority under 35 U.S.C. § 119 to Korean Patent Application No. 10-2024-0153681, filed on Nov. 1, 2024, in the Korean Intellectual Property Office, the disclosure of which is incorporated by reference herein in its entirety. INCORPORATION BY REFERENCE OF SEQUENCE LISTING The instant application contains a Sequence Listing which has been filed electronically in xml format and is hereby incorporated by reference in its entirety. Said xml copy, created on Oct. 30, 2025, is named Q315057_Sequence_listing.xml and is 28,456 bytes in size. BACKGROUND 1. Field The disclosure relates to adeno-associated virus (AAV) capsid protein variants having improved infectivity and transduction efficiency for target cells, and uses thereof. More specifically, the disclosure relates to AAV2 variant capsid proteins selected by directed evolution for gene delivery to retinal cells, recombinant AAV vectors comprising the same, and uses thereof as gene delivery vehicles to retinal cells. This study was supported by Samsung Science & Technology Foundation (Project Number: SRFC-MA2202-08). 2. Description of the Related Art Gene therapy is a method of treating genetic disorders by introducing normal genes into human cells to correct or compensate for defective or abnormal genes, and has become a key approach for treating various genetic disorders. Adeno-associated viruses (AAVs) are widely used gene delivery vectors in gene therapy because they can infect a wide variety of tissues, are nonpathogenic, and exhibit low immunogenicity. AAVs exist in various serotypes, and it is known that the host and viral properties differ depending on the serotype. For example, AAV serotype 2 (AAV2) can infect a wide range of cells, whereas AAV serotype 1 (AAV1), AAV serotype 5 (AAV5), and AAV serotype 6 (AAV6) exhibit tissue-specific infection patterns compared to AAV2; with AAV1 efficiently delivers genes to muscle, liver, airway, and the central nervous system; AAV5 to the central nervous system, liver, and retina; and AAV6 to heart, muscle, and liver. However, to be used as gene delivery vectors for gene therapy, AAV vectors must possess enhanced tissue specificity and improved efficiency in gene delivery and expression compared to existing AAV vectors. AAV capsid engineering has been employed to develop AAV vectors that meet these requirements. Directed evolution is a high-throughput screening method widely employed for engineering improved biomolecules. Directed evolution mimics the process of natural selection through repeated cycles of genetic variation and selection. Directed evolution of AAV capsids involves introducing mutations into the wild-type AAV capsid genes to generate libraries of AAV capsids with diverse sequences, from which variants exhibiting desired properties are screened to identify novel capsid variants. Recombinant AAV vectors with high tissue specificity and improved gene delivery efficiency have been developed and utilized through AAV capsid engineering (Korean Patent No. 2234930). In particular, hereditary retinal diseases are often single-gene disorders, making them promising targets for gene therapy. Several AAV variants, such as AAV2-7m8, AAV2.GL, and AAV2.NN, have been developed for this purpose. However, there remains a need for AAV variants with superior transduction capabilities that can deliver genes with high specificity to target retinal cells and efficiently induce gene expression. In this context, the inventors of the present invention have screened an AAV2 variant from an AAV library generated through directed evolution, using human retinal organoids, which exhibits enhanced gene delivery efficacy to retinal cells, thereby completing the present disclosure. SUMMARY An object of the present disclosure is to provide an AAV2 variant capsid protein exhibiting enhanced gene delivery efficiency to retinal cells. Another objective is to provide a recombinant AAV2 vector comprising an AAV2 variant capsid protein exhibiting enhanced gene delivery efficiency to retinal cells. Yet another objective is to provide a use of the recombinant AAV2 vector comprising an AAV2 variant capsid protein exhibiting enhanced gene delivery efficiency to retinal cells for the treatment of ocular diseases. Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS The above and other aspects, features, and advantages of certain embodiments of the disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which: FIG. 1 shows a schematic diagram of a directed evolution method for engineering AAV2 variant capsid proteins according to an embodiment of the present disclosure. A capsid gene (cap) encoding a wild-type AAV2 capsi