induces strong IFN-γ-based immunity. Innate lymphoid cells (ILC), in particular ILC1, are an important innate source of this protective cytokine during infection. Our objective was to determine how MyD88-dependent signaling influences ILC function during peroral compared with i.
View Article and Find Full Text PDFVitamin A (VA) deficiency and diarrheal diseases are both serious public health issues worldwide. VA deficiency is associated with impaired intestinal barrier function and increased risk of mucosal infection-related mortality. The bioactive form of VA, retinoic acid, is a well-known regulator of mucosal integrity.
View Article and Find Full Text PDFToxoplasma gondii is an orally acquired pathogen that induces strong IFN-γ based immunity conferring protection but that can also be the cause of immunopathology. The response in mice is driven in part by well-characterized MyD88-dependent signaling pathways. Here we focus on induction of less well understood immune responses that do not involve this Toll-like receptor (TLR)/IL-1 family receptor adaptor molecule, in particular as they occur in the intestinal mucosa.
View Article and Find Full Text PDFVitamin A (VA) deficiency remains prevalent in resource limited areas. Using Citrobacter rodentium infection in mice as a model for diarrheal diseases, previous reports showed reduced pathogen clearance and survival due to vitamin A deficient (VAD) status. To characterize the impact of preexisting VA deficiency on gene expression patterns in the intestines, and to discover novel target genes in VA-related biological pathways, VA deficiency in mice were induced by diet.
View Article and Find Full Text PDFFront Cell Infect Microbiol
June 2021
The gastrointestinal tract is a major portal of entry for many pathogens, including the protozoan parasite . Billions of people worldwide have acquired at some point in their life, and for the vast majority this has led to latent infection in the central nervous system. The first line of host defense against is located within the intestinal mucosa.
View Article and Find Full Text PDFVitamin A deficiency (A-) increases morbidity and mortality to gastrointestinal (GI) infection. Blocking retinoid signaling (dominant negative retinoic acid receptor, dnRAR) in intestinal epithelial cells (IEC, dnRAR) had no effect on vitamin A absorption, the expression of tight junction proteins or the integrity of the barrier. Immune cells in the gut were present in normal frequencies in the dnRAR mice, with the exception of the T cell receptor (TCR)αβ+/CD8αα cells, which were significantly lower than in wildtype littermates.
View Article and Find Full Text PDFThe apicomplexan Toxoplasma gondii induces strong protective immunity dependent upon recognition by Toll-like receptors (TLR)11 and 12 operating in conjunction with MyD88 in the murine host. However, TLR11 and 12 proteins are not present in humans, inspiring us to investigate MyD88-independent pathways of resistance. Using bicistronic IL-12-YFP reporter mice on MyD88+/+ and MyD88-/- genetic backgrounds, we show that CD11c+MHCII+F4/80- dendritic cells, F4/80+ macrophages, and Ly6G+ neutrophils were the dominant cellular sources of IL-12 in both wild type and MyD88 deficient mice after parasite challenge.
View Article and Find Full Text PDFVitamin A deficiency affects over 250 million preschool-age children worldwide and is associated with increased childhood mortality and risk of developing enteric infections. Vitamin A deficient (A-) mice developed chronic infection. A single oral dose of retinoic acid (RA) at d7 post-infection was sufficient to induce clearance of the pathogen in A- mice.
View Article and Find Full Text PDFNeurodegeneration is a critical problem in aging populations and is characterized by severe central nervous system (CNS) inflammation. Macrophages closely regulate inflammation in the CNS and periphery by taking on different activation states. The source of inflammation in many neurodegenerative diseases has been preliminarily linked to a decrease in the CNS M2 macrophage population and a subsequent increase in M1-mediated neuroinflammation.
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