---
_id: '10655'
abstract:
- lang: eng
  text: "Adeno-associated viruses (AAVs) are widely used to deliver genetic material
    in vivo to distinct cell types such as neurons or glial cells, allowing for targeted
    manipulation. Transduction of microglia is mostly excluded from this strategy,
    likely due to the cells’ heterogeneous state upon environmental changes, which
    makes AAV design challenging. Here, we established the retina as a model system
    for microglial AAV validation and optimization. First, we show that AAV2/6 transduced
    microglia in both synaptic layers, where layer preference corresponds to the intravitreal
    or subretinal delivery method. Surprisingly, we observed significantly enhanced
    microglial transduction during photoreceptor degeneration. Thus, we modified the
    AAV6 capsid to reduce heparin binding by introducing four point mutations (K531E,
    R576Q, K493S, and K459S), resulting in increased microglial transduction in the
    outer plexiform layer. Finally, to improve microglial-specific transduction, we
    validated a Cre-dependent transgene delivery cassette for use in combination with
    the Cx3cr1CreERT2 mouse line. Together, our results provide a foundation for future
    studies optimizing AAV-mediated microglia transduction and highlight that environmental
    conditions influence microglial transduction efficiency.\r\n"
acknowledged_ssus:
- _id: Bio
- _id: LifeSc
- _id: PreCl
acknowledgement: This project has received funding from the European Research Council
  (ERC) under the European Union’s Horizon 2020 research and innovation programme
  (grant agreement no. 715571). The research was supported by the Scientific Service
  Units (SSU) of IST Austria through resources provided by the Bioimaging Facility,
  the Life Science Facility, and the Pre-Clinical Facility, namely Sonja Haslinger
  and Michael Schunn for their animal colony management and support. We would also
  like to thank Chakrabarty Lab for sharing the plasmids for AAV2/6 production. Finally,
  we would like to thank the Siegert team members for discussion about the manuscript.
article_processing_charge: Yes
article_type: original
author:
- first_name: Margaret E
  full_name: Maes, Margaret E
  id: 3838F452-F248-11E8-B48F-1D18A9856A87
  last_name: Maes
  orcid: 0000-0001-9642-1085
- first_name: Gabriele M.
  full_name: Wögenstein, Gabriele M.
  last_name: Wögenstein
- first_name: Gloria
  full_name: Colombo, Gloria
  id: 3483CF6C-F248-11E8-B48F-1D18A9856A87
  last_name: Colombo
  orcid: 0000-0001-9434-8902
- first_name: Raquel
  full_name: Casado Polanco, Raquel
  id: 15240fc1-dbcd-11ea-9d1d-ac5a786425fd
  last_name: Casado Polanco
  orcid: 0000-0001-8293-4568
- first_name: Sandra
  full_name: Siegert, Sandra
  id: 36ACD32E-F248-11E8-B48F-1D18A9856A87
  last_name: Siegert
  orcid: 0000-0001-8635-0877
citation:
  ama: Maes ME, Wögenstein GM, Colombo G, Casado Polanco R, Siegert S. Optimizing
    AAV2/6 microglial targeting identified enhanced efficiency in the photoreceptor
    degenerative environment. <i>Molecular Therapy - Methods and Clinical Development</i>.
    2021;23:210-224. doi:<a href="https://doi.org/10.1016/j.omtm.2021.09.006">10.1016/j.omtm.2021.09.006</a>
  apa: Maes, M. E., Wögenstein, G. M., Colombo, G., Casado Polanco, R., &#38; Siegert,
    S. (2021). Optimizing AAV2/6 microglial targeting identified enhanced efficiency
    in the photoreceptor degenerative environment. <i>Molecular Therapy - Methods
    and Clinical Development</i>. Elsevier. <a href="https://doi.org/10.1016/j.omtm.2021.09.006">https://doi.org/10.1016/j.omtm.2021.09.006</a>
  chicago: Maes, Margaret E, Gabriele M. Wögenstein, Gloria Colombo, Raquel Casado
    Polanco, and Sandra Siegert. “Optimizing AAV2/6 Microglial Targeting Identified
    Enhanced Efficiency in the Photoreceptor Degenerative Environment.” <i>Molecular
    Therapy - Methods and Clinical Development</i>. Elsevier, 2021. <a href="https://doi.org/10.1016/j.omtm.2021.09.006">https://doi.org/10.1016/j.omtm.2021.09.006</a>.
  ieee: M. E. Maes, G. M. Wögenstein, G. Colombo, R. Casado Polanco, and S. Siegert,
    “Optimizing AAV2/6 microglial targeting identified enhanced efficiency in the
    photoreceptor degenerative environment,” <i>Molecular Therapy - Methods and Clinical
    Development</i>, vol. 23. Elsevier, pp. 210–224, 2021.
  ista: Maes ME, Wögenstein GM, Colombo G, Casado Polanco R, Siegert S. 2021. Optimizing
    AAV2/6 microglial targeting identified enhanced efficiency in the photoreceptor
    degenerative environment. Molecular Therapy - Methods and Clinical Development.
    23, 210–224.
  mla: Maes, Margaret E., et al. “Optimizing AAV2/6 Microglial Targeting Identified
    Enhanced Efficiency in the Photoreceptor Degenerative Environment.” <i>Molecular
    Therapy - Methods and Clinical Development</i>, vol. 23, Elsevier, 2021, pp. 210–24,
    doi:<a href="https://doi.org/10.1016/j.omtm.2021.09.006">10.1016/j.omtm.2021.09.006</a>.
  short: M.E. Maes, G.M. Wögenstein, G. Colombo, R. Casado Polanco, S. Siegert, Molecular
    Therapy - Methods and Clinical Development 23 (2021) 210–224.
date_created: 2022-01-23T23:01:28Z
date_published: 2021-12-10T00:00:00Z
date_updated: 2023-11-16T13:12:03Z
day: '10'
ddc:
- '570'
department:
- _id: SaSi
- _id: SiHi
doi: 10.1016/j.omtm.2021.09.006
ec_funded: 1
external_id:
  isi:
  - '000748748500019'
file:
- access_level: open_access
  checksum: 77dc540e8011c5475031bdf6ccef20a6
  content_type: application/pdf
  creator: cchlebak
  date_created: 2022-01-24T07:43:09Z
  date_updated: 2022-01-24T07:43:09Z
  file_id: '10657'
  file_name: 2021_MolTherMethodsClinDev_Maes.pdf
  file_size: 4794147
  relation: main_file
  success: 1
file_date_updated: 2022-01-24T07:43:09Z
has_accepted_license: '1'
intvolume: '        23'
isi: 1
language:
- iso: eng
license: https://creativecommons.org/licenses/by/4.0/
month: '12'
oa: 1
oa_version: Published Version
page: 210-224
project:
- _id: 25D4A630-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '715571'
  name: Microglia action towards neuronal circuit formation and function in health
    and disease
publication: Molecular Therapy - Methods and Clinical Development
publication_identifier:
  eissn:
  - 2329-0501
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: Optimizing AAV2/6 microglial targeting identified enhanced efficiency in the
  photoreceptor degenerative environment
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
volume: 23
year: '2021'
...