St Bartholomew's Hospital

About: St Bartholomew's Hospital is a healthcare organization based out in London, United Kingdom. It is known for research contribution in the topics: Population & Cancer. The organization has 11054 authors who have published 13229 publications receiving 501102 citations. The organization is also known as: St. Bartholomew's Hospital & The Royal Hospital of St Bartholomew.

Effect of erythromycin on Haemophilus influenzae endotoxin-induced release of IL-6, IL-8 and sICAM-1 by cultured human bronchial epithelial cells.

Abstract: Although several studies have demonstrated that low-dose, long-term erythromycin treatment is effective in the management of patients with chronic lower respiratory tract infections, such as chronic bronchitis, bronchiolitis and bronchiectasis, the mechanisms underlying the action of erythromycin are not clear. We have cultured human bronchial epithelial cells (HBEC) as explant cultures from surgical tissue, and have investigated the effect of erythromycin on H. influenzae endotoxin (HIE)-induced release of inflammatory mediators in these cultures. Confluent epithelial cell cultures were incubated with 100 micrograms.mL-1 HIE +/- 0.1-10 micrograms.mL-1 erythromycin and were investigated for interleukin-6 (IL-6), interleukin-8 (IL-8) and soluble intercellular adhesion molecule-1 (sICAM-1) released into the culture medium after 24 h. HIE significantly increased the release of IL-6 from 3.9 +/- 1.5 pg.micrograms-1 cellular protein (in control untreated cultures) to 12.1 +/- 1.5 pg.micrograms-1 cellular protein, and IL-8 from 83.7 +/- 8.2 pg.micrograms-1 cellular protein (in control cultures) to 225.7 +/- 44.8 pg.micrograms-1 cellular protein. Similarly, HIE led to a significantly greater release of sICAM-1 from 0.04 +/- 0.01 ng.microgram-1 cellular protein, in control cultures, to 3.8 +/- 0.9 ng.microgram-1 cellular protein. Incubation of the epithelial cultures in the presence of 0.1-10 micrograms.mL-1 erythromycin significantly blocked the HIE-induced release of IL-6, IL-8, and sICAM-1, at all concentrations of erythromycin investigated. Erythromycin also attenuated neutrophil chemotaxis and adhesion to human endothelial cells, mediated by incubation with conditioned medium obtained from HIE-exposed epithelial cell cultures, in vitro. These results suggest that H. influenzae-induced release of inflammatory mediators from airway epithelial cells could contribute to chronic airway inflammation, and that this effect may be modulated by treatment with erythromycin.

A family of clostridial and streptococcal ligand‐binding proteins with conserved C‐terminal repeat sequences

Abstract: Analysis of the derived amino acid sequences of toxins A and B from Clostridium difficile has identified an extraordinarily large number of repeat amino acid units in the C-terminal regions of the proteins. Nearly one third of each of the proteins consist of repeating units which appear, at least in the case of toxin A, to be responsible for carbohydrate binding. Similar repeat units are also found in the C-terminal region of four glucosyltransferases from Streptococcus mutans and Streptococcus downei, and in four lytic enzymes from Streptococcus pneumoniae and its bacteriophages (HB-3, Cp-1 and Cp-9). In each case the repeats constitute the ligand-binding portion of the respective enzymes. A glucan-binding protein from S. mutans, which lacks enzymatic activity, has similar repeats spanning almost the entire molecule. This family of ligand-binding proteins appears to be of modular design, with one module consisting of a repetitive ligand-binding domain located in the C-terminal region and the other module(s) providing enzymatic functions.

Regulation of T Cell Activation In Vitro and In Vivo by Targeting the OX40-OX40 Ligand Interaction: Amelioration of Ongoing Inflammatory Bowel Disease with an OX40-IgG Fusion Protein, But Not with an OX40 Ligand-IgG Fusion Protein

Abstract: OX40 is a member of the TNFR superfamily, and is found predominantly on activated CD4-positive T cells. In vitro an OX40-IgG fusion protein inhibits mitogen- and Ag-driven proliferation and cytokine release by splenocytes and lymph node T cells. In contrast, an OX40 ligand-IgG fusion protein enhanced proliferative responses. In normal mice, OX40-positive cells are observed only in lymphoid tissues, including Peyer's patches of the gut. In mice with hapten-induced colitis or IL-2 knockout mice with spontaneous colitis, OX40-positive cells are found infiltrating the lamina propria. Administration of the OX40-IgG fusion protein to mice with ongoing colitis (but not the OX40 ligand-IgG) ameliorated disease in both mouse models of inflammatory bowel disease. This was evidenced by a reduction in tissue myeloperoxidase; reduced transcripts for TNF-alpha, IL-1, IL-12, and IFN-gamma; and a reduction in the T cell infiltrate. Targeting OX40 therefore shows considerable promise as a new strategy to inhibit ongoing T cell reactions in the gut.