{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T19:44:31Z","timestamp":1790192671409,"version":"4.1.0"},"reference-count":24,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,2,13]],"date-time":"2025-02-13T00:00:00Z","timestamp":1739404800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100009619","name":"AMED","doi-asserted-by":"publisher","award":["JP22gm1510007"],"award-info":[{"award-number":["JP22gm1510007"]}],"id":[{"id":"10.13039\/100009619","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100009619","name":"AMED","doi-asserted-by":"publisher","award":["24K12770"],"award-info":[{"award-number":["24K12770"]}],"id":[{"id":"10.13039\/100009619","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ministry of Education, Culture, Sports, Science and Technology (MEXT)","award":["JP22gm1510007"],"award-info":[{"award-number":["JP22gm1510007"]}]},{"name":"Ministry of Education, Culture, Sports, Science and Technology (MEXT)","award":["24K12770"],"award-info":[{"award-number":["24K12770"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Retinitis pigmentosa (RP) is a progressive inherited retinal dystrophy (IRD) that primarily affects rod photoreceptor cells, leading to the degeneration of photoreceptors and the gradual loss of vision. While RP is one of the most studied IRDs, other neurodegenerative diseases affecting the retina and optic nerve, such as glaucoma, also involve common mechanisms of cellular stress and degeneration. Current therapeutic approaches under investigation include gene therapy, retina prosthesis, and neuroprotection. Among these approaches, gene therapy has shown promise, though challenges related to viral vector tropism and transduction efficiency persist. The adeno-associated virus (AAV) vector is commonly employed for gene delivery, but novel serotypes and engineered variants are being explored to improve specificity and efficacy. This study evaluates the gene transfer efficiency of the AAV6.2 vector following intravitreal injection into the murine retina. Male C57BL\/6 mice (9 weeks old) were intravitreally injected with 1 \u00b5L of AAV2-CMV-EGFP, AAV6-CMV-EGFP, or AAV6.2-CMV-EGFP at a titer of 3.2 \u00d7 1012 vg\/mL per eye. Retinal transduction was assessed using in vivo fluorescence imaging, flat-mount imaging, and immunohistochemistry. EGFP expression in retinal ganglion cells, M\u00fcller cells, amacrine cells, and bipolar cells was quantitatively analyzed. All three AAV serotypes effectively transduced retinal ganglion cells, but AAV6.2 exhibited enhanced transduction in M\u00fcller cells and other neuronal retinal cells, including bipolar and amacrine cells. AAV6.2 demonstrated more localized expression around retinal blood vessels compared to the diffuse expression observed with AAV2. Immunohistochemical analysis revealed that AAV6.2 had significantly higher transduction efficiency in M\u00fcller cells (p &lt; 0.001) compared to AAV2 and AAV6. AAV6.2 shows superior transduction efficiency in M\u00fcller cells, positioning it as a promising vector for gene therapies targeting retinal degenerative diseases such as RP. Its ability to effectively transduce M\u00fcller cells suggests potential applications in neuroprotection and gene replacement therapies.<\/jats:p>","DOI":"10.3390\/ijms26041580","type":"journal-article","created":{"date-parts":[[2025,2,13]],"date-time":"2025-02-13T08:01:19Z","timestamp":1739433679000},"page":"1580","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Tropism of the AAV6.2 Vector in the Murine Retina"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-1852-9781","authenticated-orcid":false,"given":"Ryo","family":"Suzuki","sequence":"first","affiliation":[{"name":"Laboratory of Photobiology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-0016, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6106-0440","authenticated-orcid":false,"given":"Yusaku","family":"Katada","sequence":"additional","affiliation":[{"name":"Laboratory of Photobiology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-0016, Japan"},{"name":"Department of Ophthalmology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Momo","family":"Fujii","sequence":"additional","affiliation":[{"name":"Laboratory of Photobiology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-0016, Japan"},{"name":"Department of Ophthalmology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Naho","family":"Serizawa","sequence":"additional","affiliation":[{"name":"Laboratory of Photobiology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-0016, Japan"},{"name":"Department of Ophthalmology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2892-9810","authenticated-orcid":false,"given":"Kazuno","family":"Negishi","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5457-2720","authenticated-orcid":false,"given":"Toshihide","family":"Kurihara","sequence":"additional","affiliation":[{"name":"Laboratory of Photobiology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-0016, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Early Treatment for Retinopathy of Prematurity Cooperative Group, Good, W.V., Hardy, R.J., Dobson, V., Palmer, E.A., and Phelps, D.L. 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