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bioRxiv · 10.1101/2023.06.05.543775

PTP1B phosphatase puts a brake on iPSC-derived neutrophil motility and antimicrobial function

Abstract

Neutrophils are rapidly recruited to sites of infection and are critical for pathogen clearance. Neutropenic patients are at high risk for fungal and bacterial infections and can benefit from granulocyte transfusion therapy. Human induced pluripotent stem cells (iPSCs) could provide a robust source of neutrophil-like cells for infusion as they can be generated in large quantities and do not require a donor. However, dampened intracellular signaling limits their cellular activation and response. Here, we show that we can engineer iPSC-derived neutrophils (iNeutrophils) for enhanced motility and anti-microbial functions. Deletion of the PTP1B phosphatase increased iNeutrophil PI3K and ERK signaling and was associated with increased F-actin polymerization, cell migration and phagocytosis. PTP1B deletion also increased production of inflammatory cytokines, including the neutrophil chemoattractant IL-8. Furthermore, PTP1B-KO iNeutrophils displayed a highly activated morphology and were more responsive to the fungal pathogen Aspergillus fumigatus. KO iNeutrophils efficiently migrated to and swarmed hyphae resulting in inhibition of fungal growth. Taken together, deletion of the PTP1B phosphatase removes the "brakes" on iPSC-derived intracellular signaling and neutrophil function. Key pointsDeletion of PTP1B increases iPSC-derived neutrophil intracellular signaling to improve motility and phagocytosis. Deletion of PTP1B enhances iPSC-derived neutrophil swarming response and ability to inhibit fungal growth.

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BibTeXRIS

Giese, M., Bennin, D., Schoen, T. J., Peterson, A., Brand, J., Jung, H. S., Dinh, H., Slukvin, I., Huttenlocher, A.. 2023-06-07. PTP1B phosphatase puts a brake on iPSC-derived neutrophil motility and antimicrobial function. https://doi.org/10.1101/2023.06.05.543775

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