10.6084/M9.FIGSHARE.C.6262004
Ahmad Samir Alfaar
Ahmad Samir
Alfaar
University Hospital Ulm
Humboldt-Universität zu Berlin
Lucas Stürzbecher
Lucas
Stürzbecher
Humboldt-Universität zu Berlin
Maria Diedrichs-Möhring
Maria
Diedrichs-Möhring
Ludwig-Maximilians-Universität München
Marion Lam
Marion
Lam
Institut de la Vision
Christophe Roubeix
Christophe
Roubeix
Institut de la Vision
Julia Ritter
Julia
Ritter
Charité - University Medicine Berlin
Technical University of Munich
Kathrin Schumann
Kathrin
Schumann
Technical University of Munich
Balasubramaniam Annamalai
Balasubramaniam
Annamalai
Medical University of South Carolina
Inga-Marie Pompös
Inga-Marie
Pompös
Humboldt-Universität zu Berlin
Bärbel Rohrer
Bärbel
Rohrer
Medical University of South Carolina
Florian Sennlaub
Florian
Sennlaub
Institut de la Vision
Nadine Reichhart
Nadine
Reichhart
Humboldt-Universität zu Berlin
Gerhild Wildner
Gerhild
Wildner
Ludwig-Maximilians-Universität München
Olaf Strauß
Olaf
Strauß
Humboldt-Universität zu Berlin
FoxP3 expression by retinal pigment epithelial cells: transcription factor with potential relevance for the pathology of age-related macular degeneration
Abstract Background Forkhead-Box-Protein P3 (FoxP3) is a transcription factor and marker of regulatory T cells, converting naive T cells into Tregs that can downregulate the effector function of other T cells. We previously detected the expression of FoxP3 in retinal pigment epithelial (RPE) cells, forming the outer blood–retina barrier of the immune privileged eye. Methods We investigated the expression, subcellular localization, and phosphorylation of FoxP3 in RPE cells in vivo and in vitro after treatment with various stressors including age, retinal laser burn, autoimmune inflammation, exposure to cigarette smoke, in addition of IL-1β and mechanical cell monolayer destruction. Eye tissue from humans, mouse models of retinal degeneration and rats, and ARPE-19, a human RPE cell line for in vitro experiments, underwent immunohistochemical, immunofluorescence staining, and PCR or immunoblot analysis to determine the intracellular localization and phosphorylation of FoxP3. Cytokine expression of stressed cultured RPE cells was investigated by multiplex bead analysis. Depletion of the FoxP3 gene was performed with CRISPR/Cas9 editing. Results RPE in vivo displayed increased nuclear FoxP3-expression with increases in age and inflammation, long-term exposure of mice to cigarette smoke, or after laser burn injury. The human RPE cell line ARPE-19 constitutively expressed nuclear FoxP3 under non-confluent culture conditions, representing a regulatory phenotype under chronic stress. Confluently grown cells expressed cytosolic FoxP3 that was translocated to the nucleus after treatment with IL-1β to imitate activated macrophages or after mechanical destruction of the monolayer. Moreover, with depletion of FoxP3, but not of a control gene, by CRISPR/Cas9 gene editing decreased stress resistance of RPE cells. Conclusion Our data suggest that FoxP3 is upregulated by age and under cellular stress and might be important for RPE function.
Immunology
figshare
2022
2022-10-23
2022-10-23
Collection
10.1186/s12974-022-02620-w
CC BY 4.0