Ascorbic acid supports ex vivo generation of plasmacytoid dendritic cells from circulating hematopoietic stem cells
Abstract
Plasmacytoid dendritic cells (pDCs) constitute a rare type of immune cell with multifaceted functions, but their potential use as a cell-based immunotherapy is challenged by the scarce cell numbers that can be extracted from blood. Here, we systematically investigate culture parameters for generating pDCs from hematopoietic stem and progenitor cells (HSPCs). Using optimized conditions combined with implementation of HSPC pre-expansion, we generate an average of 465 million HSPC-derived pDCs (HSPC-pDCs) starting from 100,000 cord blood-derived HSPCs. Furthermore, we demonstrate that such protocol allows HSPC-pDC generation from whole blood HSPCs, and these cells display a pDC phenotype and function. Using GMP compliant medium, we observe a remarkable loss of TLR7/9 responses, which is rescued by ascorbic acid supplementation. Ascorbic acid induces transcriptional signatures associated with pDC-specific innate immune pathways suggesting an undescribed role of ascorbic acid for pDC functionality. This constitutes the first protocol for generating pDCs from whole blood, and lay the foundation for investigating HSPC-pDCs for cell-based immunotherapy.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Sequencing data have been deposited in Dryad (doi:10.5061/dryad.69p8cz92z).
Article and author information
Author details
Funding
Lundbeckfonden (R238-2016-3349)
- Rasmus O Bak
Aarhus Institute of Advanced Studies, Aarhus Universitet
- Renée M van der Sluis
- Rasmus O Bak
European Union (609033)
- Rasmus O Bak
Lundbeckfonden (R238-2016-2708)
- Martin R Jakobsen
Independent Research Fund Denmark (8020-00201B)
- Martin R Jakobsen
Novo Nordisk Fonden (NNF18OC0053146)
- Martin R Jakobsen
European Union (754513)
- Renée M van der Sluis
Carlsbergfondet (CF17-0129)
- Rasmus O Bak
Carlsbergfondet (CF20-0424)
- Rasmus O Bak
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: De-identified umbilical cord blood (UCB) samples were obtained following scheduled caesarean section deliveries of healthy infants at Department of Gynecology and Obstetrics, Skejby University Hospital. Consent was obtained from the mothers, but studies on anonymized samples, such as those used in the present study, are exempt from ethical permissions in Denmark (Kommiteeloven {section sign} {section sign}14. 3).Buffy coat samples were obtained from normal healthy donors from Aarhus University Hospital Blood Bank. These were de-identified samples and studies on anonymized samples are exempt from ethical permissions in Denmark (Kommiteeloven {section sign} {section sign}14. 3).
Copyright
© 2021, Laustsen et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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