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Burns, C. M.

Publications and source records attributed to Burns, C. M..

3 recordsLinked to original sources

Seasonal dynamics in the trophic ecology and condition of a marine, benthic mesopredator, the southern stingray, Hypanus americanus

Mesopredators contribute to food web stability and as such, understanding their trophic ecology can help to predict potential consequences of ongoing ecosystem modification. Here, multi-tissue carbon and nitrogen stable isotope analysis ({delta}13C and {delta}15N) and biochemical blood parameters ({beta}-hydroxybutyrate, glucose, lactate, and osmolality) were used to assess sex, size, spatial and seasonal differences in trophic ecology and condition of southern stingrays, Hypanus americanus, in Bimini, The Bahamas. Stingrays exhibited a dietary preference for molluscs and annelids, with an ontogenetic shift towards lower {delta}13C with increasing body size indicating a shift towards more mangrove associated prey. Nitrogen isotope values showed minimal seasonal changes, but higher {delta}15N values in males indicated foraging at a higher trophic level than females. Blood {beta}-hydroxybutyrate concentrations and osmolality revealed a similar energetic state and condition between sex, size, location and season. Our results advance our understanding of the seasonal trophic ecology of a benthic, marine mesopredator and identify the southern stingray as an important trophic link in seagrass and mangrove habitats in Bimini.

ecology↗

Keratinocyte VISTA attenuates UV light-induced skin injury by suppressing cutaneous type I interferon (IFN-I) response

Persistent production of type I interferons (IFN-Is) is a hallmark of cutaneous lupus erythematosus (CLE). Ultraviolet (UV) light stimulates IFN-I response in the skin and exacerbates CLE. Here, we identify V-type immunoglobulin domain-containing suppressor of T cell activation (VISTA) as a negative regulator of both basal and UV-induced IFN-I responses in the skin and show that VISTA limits skin photosensitivity in an IFN-I- dependent manner, in part through Stimulator of Interferon Genes (STING). Furthermore, we demonstrate a novel role for VISTA in keratinocytes both at steady state and in response to UV light. Conditional deletion of VISTA in epidermal keratinocytes results in >10-fold increase in the basal skin IFN-I score and a heightened UV-induced skin injury score, which is dependent on IFN-I signaling. VISTA-targeting monoclonal antibodies suppress UV-induced IFN-I response in human keratinocytes and in mice expressing human VISTA in vivo, which also reduces UV-induced skin injury score. Our findings highlight VISTA as a potential therapeutic target for suppressing IFN-I responses in cutaneous lupus patients who suffer from UV-induced skin inflammation.

immunology↗

The role of VISTA engagement in limiting neutrophil-mediated inflammation

A growing body of evidence suggests that VISTA, an immune checkpoint inhibitory receptor, plays a central role in the regulation of innate immunity in the settings of inflammatory diseases and cancer. Neutrophils are among the cells that have the highest membrane density of surface VISTA. Targeting VISTA on neutrophils with an agonist antibody resulted in a striking reduction in their LPS-induced peripheral accumulation. Fc receptor engagement was required for anti-VISTA antibody to mediate its effects on neutrophils. Concomitant with reduced peripheral neutrophil cell numbers, anti-VISTA antibody treatment increased neutrophil cell death in the liver. In a murine model of neutrophil-mediated arthritis, agonist anti-VISTA antibody treatment ameliorated disease severity, which was associated with reduced myeloperoxidase activity in the joints. These studies add to a growing spectrum of negative regulatory functions that VISTA performs in controlling inflammation through the innate and adaptive arms of the immune system that has implications for translation into the clinic.

immunology↗