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Biology subjects

Bond, L.

Publications and source records attributed to Bond, L..

2 recordsLinked to original sources

Polymer-based culture system enables expansion of human haematopoietic stem and progenitor cells while preserving ageing-associated transcriptional programs

The global rise in ageing populations is driving an increase in age-associated diseases, including haematological malignancies such as myelodysplastic syndromes and acute myeloid leukaemia. A major challenge in addressing this burden is the lack of experimental systems that enable mechanistic studies and therapeutic screening in ageing haematopoiesis. Here, we evaluate a polymer-based ex vivo culture platform for studying human haematopoietic stem and progenitor cells (HSPCs) in the context of ageing. Using CD34+ cells from cord blood, bone marrow and peripheral blood from different age groups, we show that this culture system enables robust expansion of HSPCs while preserving age-associated transcriptional programs. Single-cell RNA sequencing revealed enrichment of key progenitor populations with consistent transcriptional identities across donors. Importantly, expanded HSPCs from older individuals retained ageing-associated signatures, such as upregulation of inflammatory pathways. These findings demonstrate that our polymer-based expansion system enables robust modelling of ageing haematopoiesis and provide a single cell transcriptional landscape of this ageing model. We envision that this system could provide a versatile platform for mechanistic studies and pharmacological testing, addressing a critical gap in experimental frameworks for age-related haematological disease research.

cell biology↗

Limited phenological and pollinator-mediated isolation among selfing and outcrossing Arabidopsis lyrata populations

Transitions from outcrossing to selfing have been a frequent evolutionary shift in plants and clearly play a role in species divergence. However, many questions remain about the initial mechanistic basis of reproductive isolation during the evolution of selfing. For instance, how important are prezygotic pre-pollination mechanisms (e.g. changes in phenology and pollinator visitation) in maintaining reproductive isolation between newly arisen selfing populations and their outcrossing ancestors? To test whether changes in phenology and pollinator visitation isolate selfing populations of Arabidopsis lyrata from outcrossing populations, we conducted a common garden experiment with plants from selfing and outcrossing populations as well as their F1 hybrids. Specifically, we asked whether there was isolation between outcrossing and selfing plants and their F1 hybrids through differences in 1) the timing or intensity of flowering; and/or 2) pollinator visitation. We found that phenology largely overlapped between plants from outcrossing and selfing populations. There were also no differences in pollinator preference related to mating system. Additionally, pollinators preferred to visit flowers on the same plant rather than exploring nearby plants, creating a large opportunity for self-fertilization. Overall, this suggests that prezygotic pre-pollination mechanisms do not strongly reproductively isolate plants from selfing and outcrossing populations of Arabidopsis lyrata.

ecology↗