Project description:Durable psoriasis improvement has been reported in a subset of psoriasis patients after treatment withdrawal of biologics blocking IL-23/Type 17 T-cell (T17) autoimmune axis. However, it is not well understood if systemic blockade of the IL-23/T17 axis promotes immune tolerance in psoriasis skin. The purpose of the study was to find translational evidence that systemic IL-17A blockade promotes regulatory transcriptome modification in human psoriasis skin immune cell subsets. We analyzed human psoriasis lesional skin 6 mm punch biopsy tissues before and after systemic IL-17A blockade using the muti-genomics approach integrating immune cell-enriched scRNA-seq (n = 18), microarray (n = 61), and immunohistochemistry (n = 61) with repository normal control skin immune cell-enriched scRNA-seq (n = 10) and microarray (n = 8) data. For the T17 axis transcriptome, systemic IL-17A blockade depleted 100% of IL17A + T-cells and 95% of IL17F + T-cells in psoriasis skin. The expression of IL23A in DC subsets was also downregulated by IL-17A blockade. The expression of IL-17-driven inflammatory mediators (IL36G, S100A8, DEFB4A, and DEFB4B) in suprabasal keratinocytes was correlated with psoriasis severity and was downregulated by IL-17A blockade. For the regulatory DC transcriptome, the proportion of regulatory semimature DCs expressing regulatory DC markers of BDCA-3 (THBD) and DCIR (CLEC4A) was increased in posttreatment psoriasis lesional skin compared to pretreatment psoriasis lesional skin. In addition, IL-17A blockade induced higher expression of CD1C and CD14, which are markers of CD1c+ CD14+ dendritic cell (DC) subset that suppresses antigen-specific T-cell responses, in posttreatment regulatory semimature DCs compared to pretreatment regulatory semimature DCs. In conclusion, systemic IL-17A inhibition not only blocks the entire IL-23/T17 cell axis but also promotes regulatory gene expression in regulatory DCs in human psoriasis skin.
Project description:The aggressiveness of invasive ductal carcinoma (IDC) of the breast is associated with increased IL-17 levels. In this study, we investigated the role of IL-17 in invasive breast tumor pathogenesis. We found that metastatic tumor-infiltrating T lymphocytes produced elevated levels of IL-17, whereas IL-17 neutralization inhibited tumor growth and prevented the migration of neutrophils and tumor cells to secondary disease sites. Tumorigenic neutrophils promote disease progression, and their depletion suppressed tumor growth. Moreover, IL-17 induced IL-6 and CXCL1 production in tumor cells, and IL-6 depletion reduced metastatic tumor growth and infiltration by Th17 cells and neutrophils. In addition, inoculation of a non-metastatic mammary tumor cell line pre-incubated with IL-17 promoted tumor growth, confirming the pro-tumor role of IL-17. Furthermore, high IL-17 expression was associated with lower disease-free survival (DFS) and worse prognosis in IDC patients. Thus, IL-17 blockade represents an attractive approach for the control of invasive breast tumors. Biopsies of patients with breast tumors
Project description:The aggressiveness of invasive ductal carcinoma (IDC) of the breast is associated with increased IL-17 levels. In this study, we investigated the role of IL-17 in invasive breast tumor pathogenesis. We found that metastatic tumor-infiltrating T lymphocytes produced elevated levels of IL-17, whereas IL-17 neutralization inhibited tumor growth and prevented the migration of neutrophils and tumor cells to secondary disease sites. Tumorigenic neutrophils promote disease progression, and their depletion suppressed tumor growth. Moreover, IL-17 induced IL-6 and CXCL1 production in tumor cells, and IL-6 depletion reduced metastatic tumor growth and infiltration by Th17 cells and neutrophils. In addition, inoculation of a non-metastatic mammary tumor cell line pre-incubated with IL-17 promoted tumor growth, confirming the pro-tumor role of IL-17. Furthermore, high IL-17 expression was associated with lower disease-free survival (DFS) and worse prognosis in IDC patients. Thus, IL-17 blockade represents an attractive approach for the control of invasive breast tumors.
Project description:Skin aging is characterized by structural and functional changes that lead to slower wound healing and higher rate of infections, which contribute to age-associated frailty. This likely depends on synergy between alterations in the local microenvironment and stem cell–intrinsic changes, underscored by pro-inflammatory microenvironments that drive pleotropic changes. To date, little is known about the precise nature and origin of the proposed age-associated inflammatory cues, or how they affect different tissue resident cell types. Based on deep single-cell RNA-sequencing of the entire dermal compartment, we now provide a comprehensive understanding of the age-associated changes in all skin cell types. We show a previously unreported skew towards an IL-17–expressing phenotype of Th cells, γδ T cells and innate lymphoid cells in aged skin. Aberrant IL-17 signaling is common to many autoimmune (e.g., rheumatoid arthritis and psoriasis) and chronic inflammatory diseases. Importantly, in vivo blockade of IL-17–triggered signaling during the aging process reduces the pro-inflammatory state by affecting immune and non-immune skin cells of both dermis and epidermis. Strikingly, IL-17 neutralization significantly delays the appearance of age-related traits, such as decreased epidermal thickness, increased cornified layer thickness and ameliorated hair follicle stem cell activation and hair shaft regeneration. Our results indicate that the aged skin shows chronic and persistent signs of inflammation, and that age-associated increased IL-17 signaling could be targeted as a strategy to prevent age-associated skin ailments in elderly.