Correction to: Limited potential of AAV-mediated gene therapy in transducing human mesenchymal stem cells for bone repair applications (Gene Therapy, (2021), 28, 12, (729-739), 10.1038/s41434-020-0182-4)

Correction to: Gene Therapyhttps://doi.org/10.1038/s41434-020-0182-4, published online 17 August 2020 During the submission process for the manuscript “Limited potential of AAV-mediated gene therapy in transducing human mesenchymal stem cells for bone repair applications”, the wrong image files were inadvertently used to prepare Fig. 4, which discusses the in vitro osteogenic potential of the studied AAV vectors. In this study, our purpose was to determine if AAV vectors expressing BMP-2 could induce osteogenic differentiation in vitro when used to transduce human bone marrow stem cells (BMSC) or human adipose derived stem cells (ASC). Osteogenic differentiation is assessed with an alizarin red staining assay. As a positive control, we included lentiviral vectors expressing BMP-2, which do induce differentiation. Together with other data in the paper, this assay was used to support our finding that transduction of the BMSCs and ASCs with AAV2-BMP-2 or AAV6-BMP-2 did not result in in vitro osteogenic differentiation. We apologize profusely for this mistake, which is a genuine error that occurred during preparation of the figure. We have created a new figure based on this experiment’s original photographs. We took the opportunity to select more consistent central areas to keep things as consistent as possible, and make it clear that the images were taken the same way, at the same time and as part of the same experiment. This raw data, with its associated metadata has been reviewed and verified by the editorial team. Importantly, the results and our conclusions have not changed - there was no osteogenic differentiation in any of the AAV-BMP transduced samples. Below, please see the revised and correct Fig. 4. We take full responsibility for this unintended error that occurred during figure preparation and would like to apologize to the editor, publisher and readers for any inconvenience. Fig. 4 In vitro osteogenic potential of P3 BMSCs and ASCs transduced with AAV2-BMP, AAV6-BMP, or LV-TSTA-BMP, as seen with alizarin red staining following culture in osteogenic medium for 7 days. Minimal alizarin red staining in AAV2 and 6 transduced MSCs, with abundant extracellular deposition of calcium in LV-TSTA transduced cells. Non-transduced cells were used as a control; no alizarin red staining was noted in non-transduced cells cultures in osteogenic media.