Biology subjects

Wilson, G. J.

Publications and source records attributed to Wilson, G. J..

7 recordsLinked to original sources

bioRxiv2025

Macrophages drive inguinal fat pad and lymph node remodelling in response to peripheral inflammation.

Adaptive immune responses are intensely energy-dependent and rely on a local source of fuel-producing molecules which have been proposed to be derived from fat pads in which mammalian lymph nodes are embedded. However, the trigger for their release has not been identified. Here we demonstrate that cutaneous inflammation is directly correlated with rapid atrophy of perinodal fat pads and increase in embedded lymph node size. We further demonstrate that the fat pad atrophy is associated with influx of a CCR2-independent, lipid metabolising, macrophage population. Macrophage depletion ameliorates fat pad atrophy, and lymph node expansion, downstream of inflamed sites. Our data therefore identify peripheral inflammation as an antigen-independent trigger of downstream fat pad and lymph node remodelling and contributes to the release of essential nutrients to drive the energetic requirements of the adaptive immune response.

immunology↗

bioRxiv2024

Eosinophils promote monocyte to macrophage differentiation and anti-bacterial immunity

Chemokine receptors control cell migration within the body. Here we reveal a novel interaction between eosinophils and monocytes in the bone marrow, indirectly controlled by the atypical chemokine receptor ACKR2. We demonstrate that ACKR2 maintains eosinophil levels within the bone marrow by scavenging CCL11. In the absence of ACKR2, elevated CCL11 leads to increased egress of eosinophils from the bone marrow into the bloodstream. As a result, eosinophil and monocyte interactions are reduced within the bone marrow niche, leading to changes in monocyte gene expression. Monocytes from ACKR2-/- mice are recruited to the tissues but are fundamentally altered in their ability to differentiate into macrophages, in the lung, peritoneal cavity and cavity wall. Bacterial elimination is impaired in ACKR2-/- mice during peritoneal infection. ACKR2 is therefore a key regulator of eosinophil-driven monocyte education in the bone marrow, required for full monocyte differentiation and macrophage function within the tissues.

immunology↗

bioRxiv2024

Mast cells are not essential for pubertal mammary gland branching.

Mast cells are long-lived, tissue-resident immune cells of the myeloid lineage with cardinal functions in allergy and atopic disease. They are now increasingly recognized also for protective roles e.g. against infections and venoms. Other functions originally assigned to mast cells in development and physiology, however, have been refuted, and for yet others, their true contribution remains uncertain. Mast cells have been implicated in promoting ductal branching in the pubertal mammary gland, the organ that produces and secretes milk in mammals, but these findings are based on mouse models that are not mast cell-specific. In this study, we therefore re-addressed the impact of mast cells on mammary gland branching using several complementary genetic models, including a new transgenic line. We report that neither constitutive deficiency of mast cells, nor their conditional ablation induced at puberty affected mammary gland branching. Our results thus dispute that mast cells promote this process in mice, at least in a unique and non-redundant manner. This study adds to a growing body of work clarifying the biological roles of mast cells, and further expands the toolbox available to the field of mast cell research.

developmental biology↗

bioRxiv2023

Disruption of maternal ACKR3 has profound effects on embryos and offspring.

ACKR3, scavenges and degrades the stem cell recruiting chemokine CXCL12 which is essential for proper embryonic, and in particular hematopoietic, development. Here we demonstrate strong expression of ACKR3 on trophoblasts. Using a pharmacological blocker we demonstrate that ACKR3 is essential for preventing movement of CXCL12 from the mother to the embryo with elevated plasma CXCL12 levels being detected in embryos from ACKR3-blocker treated mothers. Mice born to mothers treated with the blocker are lighter and shorter than those born to vehicle-treated mothers and, in addition, display profound anaemia associated with a markedly reduced bone marrow hematopoietic stem cell population. Importantly, whilst the hematopoietic abnormalities are corrected as mice age, our studies reveal a postnatal window during which offspring of ACKR3 blocker treated mice are unable to mount effective inflammatory responses to inflammatory/infectious stimuli. Overall, these data demonstrate that ACKR3 is essential for preventing CXCL12 transfer from mother to embryo and for ensuring properly regulated CXCL12 control over the development of the hematopoietic system.

developmental biology↗

bioRxiv2020

Diverse myeloid cells are recruited to the developing and inflamed mammary gland

The immune system plays fundamental roles in the mammary gland, shaping developmental processes and controlling inflammation during infection and cancer. Here we reveal unanticipated heterogeneity in the myeloid cell compartment during development of virgin, pregnant and involuting mouse mammary glands, and in milk. We investigate the functional consequences of individual and compound chemokine receptor deficiency on cell recruitment. Diverse myeloid cell recruitment was also shown in models of sterile inflammation and bacterial infection. Strikingly, we have shown that inflammation and infection can alter the abundance of terminal end buds, a key developmental structure, within the pubertal mammary gland. This previously unknown effect of inflammatory burden during puberty could have important implications for understanding the control of pubertal timing.

immunology↗

bioRxiv2019

Chemokine receptors CCR1 and ACKR2 coordinate mammary gland development

Macrophages are key regulators of developmental processes, including those involved in mammary gland development. We previously demonstrated that the atypical chemokine receptor, ACKR2, contributes to control of ductal epithelial branching in the developing mammary gland by regulating macrophage dynamics. ACKR2 is a chemokine-scavenging receptor, which mediates its effects through collaboration with inflammatory chemokine receptors (iCCRs). Here we reveal that ACKR2, and the iCCR CCR1, reciprocally regulate branching morphogenesis in the mammary gland, whereby stromal ACKR2 modulates levels of the shared ligand CCL7 to control the movement of a key population of CCR1-expressing macrophages to the ductal epithelium. In addition estrogen, which is essential for ductal elongation during puberty, upregulates CCR1 expression on macrophages. The age at which girls develop breasts is decreasing, which raises the risk of diseases including breast cancer. This study presents a previously unknown mechanism controlling the rate of mammary gland development during puberty and highlights potential therapeutic targets. SummaryIn the mammary gland during puberty, availability of the chemokine CCL7 is controlled by a scavenging receptor ACKR2 and provides a key signal to macrophages which have the receptor CCR1. Together, this controls the timing of development.

immunology↗

bioRxiv2019

A novel methodology for defining stromal expression of atypical chemokine receptors in vivo

Analysis of chemokine receptor, and atypical chemokine receptor, expression is frequently hampered by the lack of availability of high-quality antibodies and the species-specificity of those that are available. We have previously described methodology utilising Alexa-Fluor labelled chemokine ligands as versatile reagents to detect receptor expression. Previously this has been limited to haematopoietic cells and methodology for assessing expression of receptors on stromal cells has been lacking. Amongst chemokine receptors the ones most frequently expressed on stromal cells belong to the atypical chemokine receptor subfamily. These receptors do not signal in the classic sense in response to ligand but scavenge their ligands and degrade them and thus sculpt in vivo chemokine gradients. Here we demonstrate the ability to use either intratracheal, or intravenous, Alexa-Fluor labelled chemokine administration to detect stromal cell populations expressing the atypical chemokine receptor ACKR2. Using this methodology we demonstrate, for the first time, expression of ACKR2 on blood endothelial cells. This observation sets the lung aside from other tissues in which ACKR2 is exclusively expressed on lymphatic endothelial cells. In summary therefore we described a novel method for the in situ labelling of atypical chemokine receptor expressing cells appropriate for subsequent flow cytometric analysis. We propose that this methodology will work in a range of species and for a range of receptors and therefore will have significant versatility

immunology↗