Project description:T cells are key players in immunosurveillance and anti-tumor immunity. However, subsets of T helper cells producing high levels of interleukin-22 (IL-22) accumulate in primary breast and lung tumors and are linked to a more dismal outcome. Here, we demonstrate that such TH22 cells promote metastasis by abrogating NK cell-mediated immune surveillance. Using mouse models of metastatic lung and breast cancer, we find that secreted IL-22 acts directly on disseminated cancer cells expressing the IL-22 receptor (IL-22R). In turn, IL-22 induces cancer cell overexpression of CD155, which binds to activating receptor CD226 on the surface of NK cells and triggers its downregulation. This functionally impairs NK cells to promote lung metastases. Importantly, neutralization of IL-22 in vivo blocked the metastatic potential of cancer cells, suggestive of therapeutic exploitability. We confirmed the paramount role of IL-22 signaling that was associated with CD155 expression in human datasets and marked poor patient outcomes. This study reveals an immunosuppressive feedback loop activated by T cell-derived IL-22 in cancer progression, creating the rationale for the development of future targeted therapeutics.
Project description:Interleukin (IL) - 22 is a cytokine that plays a critical role in the maintenance of intestinal epithelial homeostasis. Its downstream functions are mediated through ligation of its heterodimeric receptor comprised of IL-22 receptor subunit alpha 1 (IL-22Ra1) and IL-10R2, and subsequent activation of signal transducer and activator of transcription 3 (STAT3). IL-22 signaling can induce genes necessary for intestinal epithelial cell proliferation, tissue regeneration, tight junction fortification, and production of antimicrobials. Emerging studies have also implicated IL-22 signaling in the regulation of intestinal epithelial fucosylation in mice. However, whether IL-22 regulates intestinal fucosylation in human intestinal epithelial cells and the molecular mechanisms that govern this process are unknown. Here, we show that IL-22 signaling regulates expression of the B3GNT7 transcript, which encodes a β1-3-N-acetylglucosaminyltransferase that can participate in the synthesis of poly-N-acetyllactosamine (LacNAc) chains. Additionally, we show that IL-22 signaling regulates levels of the a1-3-fucosylated Lewis X (Lex) blood group antigen and this glycan epitope is primarily displayed on heavily O-glycosylated intestinal epithelial glycoproteins. The IL-22-mediated increase in Lex antigen levels requires B3GNT7, as disruption of B3GNT7 expression moderated the IL-22-dependent increase in Lex antigen levels. Moreover, we show that increased expression of B3GNT7 alone is sufficient to promote increased display of Lex-decorated carbohydrate glycan structures primarily on O-glycosylated intestinal epithelial glycoproteins. Together, the data presented here identify B3GNT7 as a critical intermediary in IL-22-dependent induction of intestinal fucosylation of O-linked glycans and uncover a novel role for B3GNT7 in intestinal glycosylation.
Project description:Host immunity limits iron availability to pathogenic bacteria, but whether immunity limits pathogenic bacteria from accessing host heme, the major source of iron in the body, remains unclear. Using Citrobacter rodentium, a mouse enteric pathogen and Escherichia coli, a major cause of sepsis in humans as models, we find that interleukin-22, a cytokine best known for its ability to promote epithelial barrier function, also suppresses the systemic growth of bacteria by limiting iron availability to the pathogen. Using an unbiased proteomic approach to understand the mechanistic basis of IL-22 dependent iron retention in the host, we have identified that IL-22 induces the production of the plasma hemoglobin scavenger haptoglobin and heme scavenger hemopexin. Moreover, the anti-microbial effect of IL-22 depends on the induction of hemopexin expression, while haptogloblin is dispensable. Impaired pathogen clearance in infected Il22-/- mice was restored by hemopexin administration and hemopexin-deficient mice had increased pathogen loads after infection. These studies reveal a previously unrecognized host defense mechanism regulated by IL-22 that relies on the induction of hemopexin to limit heme availability to bacteria leading to suppression of bacterial growth during systemic infections.
Project description:Small interfering RNAs (siRNAs) are critical for proper development and immunity in eukaryotes1. Plants produce siRNAs with lengths of 21-, 22-, or 24- nucleotides (nt), wherein the 21- and 24-nt siRNAs mediate mRNA cleavage and DNA methylation2,3, respectively. However, the biological functions of 22-nt siRNAs remain elusive. Here we report the identification and characterization of a group of endogenous 22-nt siRNAs generated from the action of DICER-LIKE 2 (DCL2). When cytoplasmic RNA decay and DCL4 are deficient, the massive accumulation of 22-nt siRNAs causes pleiotropic growth disorders, including severe dwarfism, meristem defect, and pigmentation. Notably, two genes that encode nitrate reductases, NIA1 and NIA2, produce nearly half of the total of 22-nt siRNAs. Production of 22-nt siRNA triggers explosive self-amplification that leads to a small RNA storm, and induces dramatic translational repression both gene-specifically and globally. 22-nt siRNAs are also found to preferentially accumulate upon nitrogen deficiency, which acts to restrain plant growth and promote stress responses. Thus, our research uncovers the unique properties of 22-nt siRNAs, a previously unexplored class of plant siRNAs, and highlights the length of small RNA as a major functional determinant.
Project description:Small interfering RNAs (siRNAs) are critical for proper development and immunity in eukaryotes1. Plants produce siRNAs with lengths of 21-, 22-, or 24- nucleotides (nt), wherein the 21- and 24-nt siRNAs mediate mRNA cleavage and DNA methylation2,3, respectively. However, the biological functions of 22-nt siRNAs remain elusive. Here we report the identification and characterization of a group of endogenous 22-nt siRNAs generated from the action of DICER-LIKE 2 (DCL2). When cytoplasmic RNA decay and DCL4 are deficient, the massive accumulation of 22-nt siRNAs causes pleiotropic growth disorders, including severe dwarfism, meristem defect, and pigmentation. Notably, two genes that encode nitrate reductases, NIA1 and NIA2, produce nearly half of the total of 22-nt siRNAs. Production of 22-nt siRNA triggers explosive self-amplification that leads to a small RNA storm, and induces dramatic translational repression both gene-specifically and globally. 22-nt siRNAs are also found to preferentially accumulate upon nitrogen deficiency, which acts to restrain plant growth and promote stress responses. Thus, our research uncovers the unique properties of 22-nt siRNAs, a previously unexplored class of plant siRNAs, and highlights the length of small RNA as a major functional determinant.
Project description:Small interfering RNAs (siRNAs) are critical for proper development and immunity in eukaryotes1. Plants produce siRNAs with lengths of 21-, 22-, or 24- nucleotides (nt), wherein the 21- and 24-nt siRNAs mediate mRNA cleavage and DNA methylation2,3, respectively. However, the biological functions of 22-nt siRNAs remain elusive. Here we report the identification and characterization of a group of endogenous 22-nt siRNAs generated from the action of DICER-LIKE 2 (DCL2). When cytoplasmic RNA decay and DCL4 are deficient, the massive accumulation of 22-nt siRNAs causes pleiotropic growth disorders, including severe dwarfism, meristem defect, and pigmentation. Notably, two genes that encode nitrate reductases, NIA1 and NIA2, produce nearly half of the total of 22-nt siRNAs. Production of 22-nt siRNA triggers explosive self-amplification that leads to a small RNA storm, and induces dramatic translational repression both gene-specifically and globally. 22-nt siRNAs are also found to preferentially accumulate upon nitrogen deficiency, which acts to restrain plant growth and promote stress responses. Thus, our research uncovers the unique properties of 22-nt siRNAs, a previously unexplored class of plant siRNAs, and highlights the length of small RNA as a major functional determinant.
Project description:Small interfering RNAs (siRNAs) are critical for proper development and immunity in eukaryotes1. Plants produce siRNAs with lengths of 21-, 22-, or 24- nucleotides (nt), wherein the 21- and 24-nt siRNAs mediate mRNA cleavage and DNA methylation2,3, respectively. However, the biological functions of 22-nt siRNAs remain elusive. Here we report the identification and characterization of a group of endogenous 22-nt siRNAs generated from the action of DICER-LIKE 2 (DCL2). When cytoplasmic RNA decay and DCL4 are deficient, the massive accumulation of 22-nt siRNAs causes pleiotropic growth disorders, including severe dwarfism, meristem defect, and pigmentation. Notably, two genes that encode nitrate reductases, NIA1 and NIA2, produce nearly half of the total of 22-nt siRNAs. Production of 22-nt siRNA triggers explosive self-amplification that leads to a small RNA storm, and induces dramatic translational repression both gene-specifically and globally. 22-nt siRNAs are also found to preferentially accumulate upon nitrogen deficiency, which acts to restrain plant growth and promote stress responses. Thus, our research uncovers the unique properties of 22-nt siRNAs, a previously unexplored class of plant siRNAs, and highlights the length of small RNA as a major functional determinant.
Project description:Small interfering RNAs (siRNAs) are critical for proper development and immunity in eukaryotes1. Plants produce siRNAs with lengths of 21-, 22-, or 24- nucleotides (nt), wherein the 21- and 24-nt siRNAs mediate mRNA cleavage and DNA methylation2,3, respectively. However, the biological functions of 22-nt siRNAs remain elusive. Here we report the identification and characterization of a group of endogenous 22-nt siRNAs generated from the action of DICER-LIKE 2 (DCL2). When cytoplasmic RNA decay and DCL4 are deficient, the massive accumulation of 22-nt siRNAs causes pleiotropic growth disorders, including severe dwarfism, meristem defect, and pigmentation. Notably, two genes that encode nitrate reductases, NIA1 and NIA2, produce nearly half of the total of 22-nt siRNAs. Production of 22-nt siRNA triggers explosive self-amplification that leads to a small RNA storm, and induces dramatic translational repression both gene-specifically and globally. 22-nt siRNAs are also found to preferentially accumulate upon nitrogen deficiency, which acts to restrain plant growth and promote stress responses. Thus, our research uncovers the unique properties of 22-nt siRNAs, a previously unexplored class of plant siRNAs, and highlights the length of small RNA as a major functional determinant.
Project description:Metabolic dysfunction-associated steatohepatitis (MASH) is the most prevalent cause of liver disease worldwide, with a single approved therapeutics. Previous research has shown that interleukin-22 (IL-22) can suppress beta-cell stress, reduce local islet inflammation, restore appropriate insulin production, reverse hyperglycemia, and ameliorate insulin resistance in preclinical models of diabetes. In clinical trials long-acting forms of IL-22 have led to increased proliferation in the skin and intestine, where the IL-22RA1 receptor is highly expressed. To maximise beneficial effects whilst reducing the risk of epithelial proliferation and cancer, we designed short-acting IL-22-bispecific biologic drugs that successfully targeted the liver and pancreas. 10-fold lower doses of these bispecific biologics exceeded the beneficial effects of native IL-22 in multiple preclinical models of MASH, without off-target effects. Treatment restored glycemic control, markedly reduced hepatic steatosis, inflammation, and fibrogenesis. These short-acting IL-22-bispecific targeted biologics are a promising new therapeutic approach for MASH.