Biology subjects

Angeloni, L.

Publications and source records attributed to Angeloni, L..

3 recordsLinked to original sources

bioRxiv2026

Polarization affects viscoelasticity and podosome distribution of primary human macrophages

Macrophages are essential cells of the innate immune system that regulate wound healing and tissue homeostasis. They exert diverse functions, depending on their polarization state, which can lead to either functional healing of the tissue or fibrosis. Macrophage polarization state is affected by both the local biochemical and mechanical microenvironment within the tissue, suggesting a possible dependence of macrophage function on cell mechanical state, which has been poorly explored to date. In this study, we provide a systematic and quantitative characterization of the viscoelastic properties of unstimulated, pro-inflammatory, and anti-inflammatory monocyte-derived primary human macrophages at the single-cell level using atomic force microscopy. Pro-inflammatory macrophages exhibited a lower elastic modulus (E = 458.8 {+/-} 179.9 Pa) and a more dissipative response (low frequency exponent = 0.22 {+/-} 0.03) than anti-inflammatory macrophages (E = 716 {+/-} 345.6 Pa and = 0.15 {+/-} 0.04). These differences in mechanical properties were independent of cell morphology but correlated with differences in podosome distribution with pro-inflammatory macrophages exhibiting a dispersed distribution, and anti-inflammatory macrophages a more clustered distribution. This study identifies polarization-dependent mechanical differences in human primary macrophages and provides a quantitative experimental framework for future work in macrophage mechanobiology.

biophysics↗

bioRxiv2021

Is energetics or competition a stronger driver of male smallmouth bass seasonal reproductive timing?

Intraspecific competitive ability is often associated with body size and has been shown to influence reproductive timing in many species. However, energetic constraints provide an alternative explanation for size-related differences of reproductive timing. In temperate fishes that experience a winter starvation period, for instance, a negative allometric relationship between body size and winter energy loss might explain why larger males spawn earlier in a season than smaller males, especially in fishes that exhibit paternal care, which is energetically costly and limits parental foraging opportunities. Male smallmouth bass, Micropterus dolomieu, defend nesting territories in which they care for offspring over an extended period. In northern populations, males rely on energy reserves over a winter starvation period and in spring must recoup energy losses before initiating reproduction, making them ideal systems in which to study contributions of competition and energetic allometry on differences of reproductive timing. Here, we harness data on parental male M. dolomieu from a 10-year study and show that larger males required fewer degree days-a measure of thermal energy experienced-in spring before they spawned each year and that the time of peak seasonal reproduction in the population was negatively related to the number of degree days accumulated before reproduction started. Furthermore, we found that growth of individual males between seasons better predicted changes in timing of reproduction than changes in size relative to competitors. Together, these results suggest that timing of reproduction in this population is more strongly influenced by energetic constraints than size-based competition amongst males.

animal behavior and cognition↗

bioRxiv2019

Genetic rescue without genomic swamping in wild populations

Gene flow is an enigmatic evolutionary force because it can limit adaptation but can also help populations escape inbreeding depression. Manipulating gene flow for conservation purposes is a controversial, but potentially powerful management strategy. We use multigenerational pedigrees and genomics to test demographic and evolutionary consequences of manipulating gene flow in two isolated wild Trinidadian guppy populations. We found that on average, hybrids lived longer and reproduced more. Despite overall genome-wide homogenization, alleles potentially associated with local adaptation were not entirely swamped by gene flow. Our results suggest that combining new genomic variation from immigrants with potentially adaptive variation from the recipient population resulted in highly fit hybrids and subsequent increases in population size. Contrary to the prevailing view that gene flow constrains adaptation, our study shows that immigration can produce long-term fitness benefits in small populations without swamping locally adaptive variation.

evolutionary biology↗