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Schorey, J.

Publications and source records attributed to Schorey, J..

3 recordsLinked to original sources

Replication-deficient Adenovirus 5 Serotypes Induce Type I Interferon and enhance BCG-mediated Immune Response in Co-infected Murine Macrophages

Tuberculosis (TB) remains a leading global cause of infectious mortality due, in part, to the limited efficacy of the Mycobacterium bovis BCG vaccine against pulmonary TB. Previous studies in mice have shown that stimulating type I interferon (IFN) signaling during BCG vaccination can bolster protection against Mycobacterium tuberculosis, yet clinically feasible delivery strategies for this approach are lacking. Adenoviral vectors, which induce potent type I IFN responses and are utilized in approved vaccine platforms, represent a promising adjuvant strategy. To evaluate the host immune response to this combination, bone marrow-derived murine macrophages were co-infected with replication-deficient adenovirus and BCG. Adenovirus-infected macrophages elicited a robust type I IFN response via the cGAS/STING pathway. Compared to BCG infection alone, co-infected macrophages exhibited additive expression of genes with known host-protective roles against M. tuberculosis. Conversely, co-infection with BCG suppressed adenovirus-induced type I IFN signaling and diminished the production of IFN-stimulated genes compared to adenovirus infection alone. Together, these findings reveal a complex regulatory interplay during adenovirus and BCG co-infection. While BCG partially restricts adenoviral IFN induction, the co-infection still drives an enhanced host-protective gene profile, suggesting that adenoviral vectors could serve as a viable platform to modulate innate immunity and improve BCG vaccine efficacy. IMPORTANCETuberculosis (TB) remains the leading cause of death by a single infectious organism with approximately 1.25 million deaths annually. M. bovis BCG remains the only approved vaccine for TB; however, its efficacy against the contagious and most common pulmonary form of the disease is limited. There have been numerous attempts to improve BCG efficacy, but these approaches have not resulted in any clinically approved vaccine. We propose that BCG combined with a replication-deficient adenovirus presents a way to bolster vaccine-conferred protection as the combination may elicit a robust innate immune response and drive a more protective T cell response. Moreover, BCG and replication-deficient adenoviruses have well-assessed safety profiles and decades of studies regarding their use in patients. The significance of our work is in leveraging their complementary immunology to function as a combined vaccine platform. This approach presents a novel and clinically feasible approach to improve the BCG vaccine.

microbiology↗

Large extracellular vesicles regulate endothelial angiogenic potential via paracrine and autocrine signaling

Angiogenesis, a process typically associated with tumor growth and development, is often linked to advanced disease and poor clinical outcomes. Tumor cells establish a pro-angiogenic microenvironment through the release of paracrine signaling mediators including extracellular vesicles (EVs). EVs have been shown to facilitate intercellular communication and encompass a diverse range of secreted vesicles, including small EVs (sEVs) which range in size from [~]60 to 100nm and large EVs (L-EVs) which are even more diverse and range from 200nm to >1m in size. Despite advancements in anti-angiogenic cancer therapies, such as bevacizumab, late-stage tumors, including advanced melanomas, exhibit mixed clinical responses. In this study, we elucidate a unique role for melanoma-derived L-EVs in promoting bevacizumab-insensitive endothelial angiogenic phenotypes. This L-EV-mediated increase in endothelial tube formation is sensitive to the effects of sorafenib, a multi-kinase inhibitor, but not SU5416, a selective VEGF-receptor inhibitor. We also demonstrate that melanoma L-EVs contain VEGF as luminal cargo and induce paracrine effects by modulating the endothelial EV secretome. The release from endothelial cells of soluble VEGF, EVs, and pro-angiogenic cytokines such as IL-8, MIF, and PAI-1 drive sustained endothelial tube formation through autocrine signaling. Finally, we show that EV subtypes have distinct effects on the acquisition of angiogenic phenotypes and their roles vary with tumor type. These findings provide new insight into the mechanisms of angiogenic therapy resistance in melanoma and demonstrate the differential functions of EV subtypes in angiogenesis across tumor types.

cancer biology↗

Extracellular Vesicles promote host immunity during an M. tuberculosis infection through RNA Sensing

Extracellular vesicles (EVs) have been shown to carry microbial components and function in the host defense against infections. In this study, we demonstrate that Mycobacterium tuberculosis (M.tb) RNA is delivered into macrophage-derived EVs through an M.tb SecA2-dependent pathway, and that EVs released from M.tb-infected macrophages stimulate a host RIG-I/MAVS/TBK1/IRF3 RNA sensing pathway, leading to type I interferon production in recipient cells. These EVs also promote, in a RIG-I/MAVS-dependent manner, the maturation of M.tb-containing phagosomes through a noncanonical LC3 modification, leading to increased bacterial killing. Moreover, treatment of M.tb-infected macrophages or mice with a combination of moxifloxacin and EVs, isolated from M.tb-infected macrophages, significantly lowered bacterial burden relative to either treatment alone. We propose that EVs, which are preferentially removed by macrophages in vivo, may be developed in combination with effective antibiotics as a novel approach to treat drug-resistant TB.

microbiology↗