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Systemic immune responses caused by chronic hypercholesterolaemia contribute to atherosclerosis initiation, progression and complications 1 . However, individuals often change their dietary habits over time 2 , and the effects of an alternating high-fat diet (HFD) on atherosclerosis remain unclear. Here, to address this relevant issue, we developed a protocol using atherosclerosis-prone mice to compare an alternating versus continuous HFD while maintaining similar overall exposure periods. We found that an alternating HFD accelerated atherosclerosis in Ldlr -/- and Apoe -/- mice compared with a continuous HFD. This pro-atherogenic effect of the alternating HFD was also observed in Apoe -/- Rag2 -/- mice lacking T, B and natural killer T cells, ruling out the role of the adaptive immune system in the observed phenotype. Discontinuing the HFD in the alternating HFD group downregulated RUNX1 3 , promoting inflammatory signalling in bone marrow myeloid progenitors. After re-exposure to an HFD, these cells produced IL-1β, leading to emergency myelopoiesis and increased neutrophil levels in blood. Neutrophils infiltrated plaques and released neutrophil extracellular traps, exacerbating atherosclerosis. Specific depletion of neutrophils or inhibition of IL-1β pathways abolished emergency myelopoiesis and reversed the pro-atherogenic effects of the alternating HFD. This study highlights the role of IL-1β-dependent neutrophil progenitor reprogramming in accelerated atherosclerosis induced by alternating HFD., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Andean highland soils contain significant quantities of soil organic carbon (SOC); however, more efforts still need to be made to understand the processes behind the accumulation and persistence of SOC and its fractions. This study modeled SOC variables-SOC, refractory SOC (RSOC), and the 13 C isotope composition of SOC (δ 13 C SOC )-using machine learning (ML) algorithms in the Central Andean Highlands of Peru, where grasslands and wetlands ("bofedales") dominate the landscape surrounded by Junin National Reserve. A total of 198 soil samples (0.3 m depth) were collected to assess SOC variables. Four ML algorithms-random forest (RF), support vector machine (SVM), artificial neural networks (ANNs), and eXtreme gradient boosting (XGB)-were used to model SOC variables using remote sensing data, land-use and land-cover (LULC, nine categories), climate topography, and sampled physical-chemical soil variables. RF was the best algorithm for SOC and δ 13 C SOC prediction, whereas ANN was the best to model RSOC. "Bofedales" showed 2-3 times greater SOC (11.2 ± 1.60%) and RSOC (1.10 ± 0.23%) and more depleted δ 13 C SOC (- 27.0 ± 0.44 ‰) than other LULC, which reflects high C persistent, turnover rates, and plant productivity. This highlights the importance of "bofedales" as SOC reservoirs. LULC and vegetation indices close to the near-infrared bands were the most critical environmental predictors to model C variables SOC and δ 13 C SOC . In contrast, climatic indices were more important environmental predictors for RSOC. This study's outcomes suggest the potential of ML methods, with a particular emphasis on RF, for mapping SOC and its fractions in the Andean highlands., Supplementary Information: The online version contains supplementary material available at 10.1007/s10021-024-00928-7., (© The Author(s) 2024.)

In high-risk myeloid malignancy, relapse is reduced using cord blood transplant (CBT) but remains the principal cause of treatment failure. We previously described T-cell expansion in CBT recipients receiving granulocyte transfusions. We now report the safety and tolerability of such transfusions, T-cell expansion data, immunophenotype, cytokine profiles and clinical response in children with post-transplant relapsed acute leukaemia who received T-replete, HLA-mismatched CBT and pooled granulocytes within a phase I/II trial (ClinicalTrials.Gov NCT05425043). All patients received the transfusion schedule without significant clinical toxicity. Nine of ten patients treated had detectable measurable residual disease (MRD) pre-transplant. Nine patients achieved haematological remission, and eight became MRD negative. There were five deaths: transplant complications (n = 2), disease (n = 3), including two late relapses. Five patients are alive and in remission with 12.7 months median follow up. Significant T-cell expansion occurred in nine patients with a greater median lymphocyte count than a historical cohort between days 7-13 (median 1.73 × 10 9 /L vs. 0.1 × 10 9 /L; p < 0.0001). Expanded T-cells were predominantly CD8 + and effector memory or TEMRA phenotype. They exhibited markers of activation and cytotoxicity with interferon-gamma production. All patients developed grade 1-3 cytokine release syndrome (CRS) with elevated serum IL-6 and interferon-gamma., (© 2023 The Authors. British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd.)