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bioRxiv · 10.1101/2025.10.08.679225

DNMT3A-R882 mutations intrinsically drive dysfunctional neutropoiesis from human haematopoietic stem cells

Abstract

Clonal haematopoiesis (CH) arises from the expansion of hematopoietic stem cells (HSCs) carrying leukaemia-associated somatic mutations. CH is linked to pathological immune dysregulation and a greater risk of age-related inflammatory diseases. Yet, how CH mutations impact HSC differentiation into immune effector cells remains understudied. Here, we report a single-cell resolution functional and multi-omic investigation of HSC clonal and differentiation dynamics in individuals with DNMT3A-R882 CH. DNMT3A-R882 reshapes the clonal architecture of haematopoiesis towards an aged phylogenetic structure. Functionally, DNMT3A-R882 HSCs produce decreased monocytic output but more abundant and mature neutrophil progeny compared to WT HSCs in the same individual. Whereas DNMT3A-R882 myeloid progenitors display attenuated inflammatory transcriptional programmes, DNMT3A- R882 mature neutrophils acquire proinflammatory and immunomodulatory features typical of maladaptive immunity and CH co-morbidities. Our findings, validated in humanised mice, identify aberrant DNMT3A-R882 HSC-driven neutropoiesis as a key link between CH, immune dysregulation and risk of inflammatory disease.

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BibTeXRIS

Mantica, G., Vedi, A., Tuval, A., Huerga Encabo, H., Hayler, D., Krzywon, A., Mitchell, E., Dunn, W. G., Biezuner, T., Bastos, H. P., Sham, K., Santoro, A., Lee, J., Williams, N., Danin, A., Chapal, N., Moskovitz, Y., Arruda, A., Fiorillo, E., Orru, V., Marongiu, M., McKinney, E., Cucca, F., Collin, M., Minden, M., Campbell, P., Vassiliou, G. S., Fabre, M. A., Nangalia, J., Bonnet, D., Shlush, L., Laurenti, E.. 2025-10-08. DNMT3A-R882 mutations intrinsically drive dysfunctional neutropoiesis from human haematopoietic stem cells. https://doi.org/10.1101/2025.10.08.679225

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