Search results for "macrophage"

Activation and methotrexate-mediated suppression of the TNF alpha promoter in T cells and macrophages.

1998

The yopJ locus is required for Yersinia-mediated inhibition of NF-kappaB activation and cytokine expression: YopJ contains a eukaryotic SH2-like doma…

1998

Upon exposure to bacteria, eukaryotic cells activate signalling pathways that result in the increased expression of several defence-related genes. Here, we report that the yopJ locus of the enteropathogen Yersinia pseudotuberculosis encodes a protein that inhibits the activation of NF-kappaB transcription factors by a mechanism(s), which prevents the phosphorylation and subsequent degradation of the inhibitor protein IkappaB. Consequently, eukaryotic cells infected with YopJ-expressing Yersinia become impaired in NF-kappaB-dependent cytokine expression. In addition, the blockage of inducible cytokine production coincides with yopJ-dependent induction of apoptosis. Interestingly, the YopJ pr…

Differential Roles of Macrophages in Diverse Phases of Skin Repair

2010

Abstract Influx of macrophages plays a crucial role in tissue repair. However, the precise function of macrophages during the healing response has remained a subject of debate due to their functional dichotomy as effectors of both tissue injury and repair. We tested the hypothesis that macrophages recruited during the diverse phases of skin repair after mechanical injury exert specific functions to restore tissue integrity. For this purpose, we developed a mouse model that allows conditional depletion of macrophages during the sequential stages of the repair response. Depletion of macrophages restricted to the early stage of the repair response (inflammatory phase) significantly reduced the…

Longitudinal analysis of Mycobacterium tuberculosis 19-kDa antigen-specific T cells in patients with pulmonary tuberculosis: association with disease…

2003

CD8(+) T cells play a central role in immune protection against infection with Mycobacterium tuberculosis. One of the target epitopes for anti-M. tuberculosis directed CD8(+) T cells is the HLA-A2-restricted 19-kDa lipoprotein peptide VLTDGNPPEV. T cell clones directed against this epitope recognized not only the nominal peptide ligand, but also a closely related peptide (VPTDPNPPEV) from the HIV envelope gp120 (HIV(env) gp120) protein characterized by IFN-gamma release. This cross-reactivity was confirmed in ex vivo in M. tuberculosis 19-kDa tetramer-sorted T cells from patients with tuberculosis and in HIVgp120 tetramer-reactive T cells sorted from HIV(+) patients. M. tuberculosis 19-kDa …

Damping excessive inflammation and tissue damage in Mycobacterium tuberculosis infection by Toll IL-1 receptor 8/single Ig IL-1-related receptor, a n…

2007

Abstract Toll IL-1R 8/single Ig IL-1-related receptor (TIR8/SIGIRR) is a member of the IL-1R family, expressed by epithelial tissues and immature dendritic cells, and is regarded as a negative regulator of TLR/IL-1R signaling. Tir8-deficient mice were rapidly killed by intranasal administration of low doses of Mycobacterium tuberculosis, despite controlling efficiently the number of viable bacilli in different organs. Tir8−/−-infected mice showed an increased number of neutrophils and macrophages in the lungs; however, mycobacteria-specific CD4 and CD8 T cells were similar in Tir8−/− and Tir8+/+ mice. Exaggerated mortality of Tir8−/− mice was due to massive liver necrosis and was accompanie…

IL-4 depletion enhances host resistance and passive IgA protection against tuberculosis infection in BALB/c mice.

2007

The influence of Th2 cytokines in tuberculosis has been a matter of dispute. Here we report that IL-4 has a profound regulatory effect on the infection of BALB/c mice with Mycobacterium tuberculosis. Depletion of IL-4 with a neutralizing mAb caused only evanescent reduction of lung infection, but when combined with i.n. inoculations of IgA anti-mycobacterial alpha-crystallin mAb and mouse rIFN-gamma, we observed a 40-fold reduction of the bacterial counts in the lungs at 3 wks following i.n. infection (p<0.001). In genetically deficient IL-4-/- BALB/c mice, infection in both lung and spleen was substantially reduced for up to 8 wks without further treatment. Reconstitution of IL-4-/- mice w…

Relevance of the macrophage phenotype in mucosal regeneration in Inflammatory Bowel Disease

2015

La enfermedad Inflamatoria Intestinal (EII) es una enfermedad crónica, recidivante, de carácter sistémico que afecta principalmente al tracto gastrointestinal. Esta patología engloba dos entidades clínicas, la Enfermedad de Crohn (EC) y la Colitis Ulcerosa (CU), que difieren en algunos aspectos pero comparten la disrupción de la barrera epitelial y la respuesta exacerbada del sistema inmunológico a la flora bacteriana. La etiología de la enfermedad es desconocida pero se sabe que factores genéticos (tanto alteraciones a nivel genético como la presencia de miRNAs), ambientales (tales como la dieta, tabaco, actividad física o la calidad del sueño), flora intestinal y sistema inmunológico cont…

Association of AUUUA-binding Protein with A + U-rich mRNA during nucleo-cytoplasmic transport

1992

Resealed nuclear envelope (NE) vesicles from rat liver containing entrapped exogenous RNA were used to study the effect of adenosine+uridine binding factor (AUBF), present in cytosolic cell extracts, on ATP-dependent transport of A+U-rich RNA (AU+RNA) and A+U-free RNA (AU-RNA) across the NE. This factor specifically binds to A+U-rich sequences present in the 3' untranslated regions of lymphokine and cytokine mRNAs, containing overlapping AUUUA boxes (granulocyte-macrophage colony stimulating factor, interleukin-3). Addition of AUBF to the extravesicular compartment markedly increased the efflux of the in vitro transcribed, capped and polyadenylated AU+ RNAs. Export of entrapped AU- control …

In Vivo Modulation of Angiogenesis and Immune Response on a Collagen Matrix via Extracorporeal Shockwaves

2020

The effective management of tissue integration and immunological responses to transplants decisively co-determines the success of soft and hard tissue reconstruction. The aim of this in vivo study was to evaluate the eligibility of extracorporeal shock wave therapy (ESWT) with respect to its ability to modulate angiogenesis and immune response to a collagen matrix (CM) for tissue engineering in the chorioallantoic membrane (CAM) assay, which is performed with fertilized chicken eggs. CM were placed on the CAM on embryonic development day (EDD) 7

High levels of HIF-2α highlight an immature neural crest-like neuroblastoma cell cohort located in a perivascular niche

2007

High HIF-2alpha protein levels in the sympathetic nervous system-derived childhood tumour neuroblastoma as well as immature phenotype correlate to unfavourable outcome. Here we show that a small subset of perivascularly located, strongly HIF-2alpha-positive tumour cells (MYCN amplified) lacks expression of differentiation markers, but expresses neural crest and early sympathetic progenitor marker genes such as Notch-1, HES-1, c-Kit, dHAND, and vimentin. HIF-2alpha- and CD68-positive tumour-associated macrophages were frequently found close to the immature and HIF-2alpha-positive neuroblastoma cells and as VEGF levels are high in the perivascular niche, we hypothesize that neuroblastoma neur…