The murine Nramp1 (natural-resistance-associated macrophage protein) locus confers innate resistance against intracellular macrophage pathogens. The gene encodes a transporter molecule, which is rapidly recruited to the phagosome. Nramp1 functions as an iron transporter by transporting iron into the phagosome. Within the phagosome iron mediates anti-microbial killing by hydroxyl radical formati...

Mutations at the Nramp1 locus in vivo cause susceptibility to infection by unrelated intracellular microbes. Nramp1 encodes an integral membrane protein abundantly expressed in the endosomal-lysosomal compartment of macrophages and is recruited to the phagosomal membrane following phagocytosis. The mechanism by which Nramp1 affects the biochemical properties of the phagosome to control microbia...

Mutations at the Nramp1 gene cause susceptibility to infections with intracellular pathogens. In human blood, polymorphonuclear (PMN) leukocytes are the most abundant site of NRAMP1 messenger RNA (mRNA) expression, suggesting that NRAMP1 plays an important role in the activity of these cells. By Northern blot analysis, NRAMP1 mRNA was only detected in most mature neutrophils from bone marrow (b...

In mammals, natural-resistance-associated macrophage protein 1 (Nramp1) regulates macrophage activation and is associated with infectious and autoimmune diseases. Nramp2 is associated with anaemia. Both belong to a highly conserved eukaryote/prokaryote protein family. We used Xenopus oocytes to demonstrate that, like Nramp2, Nramp1 is a bivalent cation (Fe2+, Zn2+ and Mn2+) transporter. Strikin...

As the natural resistance-associated macrophage protein 1 Nramp1 (also known as Slc11a1) modulates Kupffer cell (KC) activation, and KC are responsible for the early phase of warm ischemia/reperfusion (I/R) to the liver, we hypothesized that livers of Nramp1(-/-) mice will be protected from early-phase I/R injury compared with livers of Nramp1(+/+) mice. To test our hypothesis, we induced parti...

Salmonella enterica serovar Typhimurium is an intracellular pathogen and a main cause of food-borne illness. In this study, a quantitative PCR (qPCR)-based competitive index (CI) method was developed to simultaneously compare the growth of multiple Salmonella strains. This method was applied to a mixture of 17 Salmonella mutants lacking regulator genes, and their survival ratios were compared b...

The macrophage resistance gene NRAMP1 regulates priming/activation of macrophages for enhanced TNF alpha, IL 1 beta, and MHC class II expression. Since all of these functions are of potential importance in the induction or maintenance or both of autoimmune disease, samples from the Arthritis and Rheumatism Council's repository of multicase rheumatoid arthritis families were typed for a dinucleo...

Nramp1 is an important determinant of innate resistance of macrophages to the growth of intracellular microorganisms. We previously showed that Nramp1 functions to transport iron from the cytoplasm into phagosomes of Mycobacterium avium-infected macrophages. The purpose of this investigation was to further characterize the factors that regulate Nramp1-mediated iron transport into phagosomes. Tr...

The mechanisms underlying the survival of intracellular parasites such as mycobacteria in host macrophages remain poorly understood. In mice, mutations at the Nramp1 gene (for natural resistance-associated macrophage protein), cause susceptibility to mycobacterial infections. Nramp1 encodes an integral membrane protein that is recruited to the phagosome membrane in infected macrophages. In this...

Bacterial survival in macrophages can be affected by the natural resistance-associated macrophage protein 1 (Nramp1; also known as solute carrier family 11 member a1 or Slc11a1) which localizes to phagosome membranes and transports divalent cations, including iron. Little is known about the role of Nramp1 in Burkholderia infection, in particular whether this differs for pathogenic species like ...