We evaluated the effects of murine recombinant interleukin-4 (rIL-4) on murine peritoneal macrophages. We showed a marked, dose-dependent stimulation of respiratory oxidative burst by IL-4 in peptone-elicited murine peritoneal macrophages. This effect was abolished by a neutralizing monoclonal antibody (mAb) to rIL-4 confirming that the enhanced chemiluminescence was due to IL-4. In contrast, r...

BACKGROUND The need to develop new, improved treatments for tuberculosis (TB) remains urgent, and the repurposing of existing drugs represents a possible shortcut to market. Recently, there has been significant interest in host-directed adjuvant therapy to enhance bacillary killing. HMG-CoA reductase inhibitors (statins), which are among the most commonly prescribed drugs, have immunomodulatory...

Long-term exposure to pharmacological agents can select for cells that overexpress efflux transporters. We previously showed that mouse J774 macrophages cultivated for a prolonged period of time with toxic concentrations of the fluoroquinolone ciprofloxacin overexpress the efflux transporter Mrp4 and display a reduced accumulation of this antibiotic, but no change in the accumulation of moxiflo...

OBJECTIVE ATP-binding cassette transporter A1 (ABCA1) mediates the efflux of lipids from cells to lipid-poor apolipoproteins. In this article, we characterize the effect of probucol on cellular ABCA1-mediated lipid efflux. METHODS AND RESULTS Probucol inhibited cholesterol efflux up to 80% in J774 macrophages expressing ABCA1. In Fu5AH hepatoma cells that contain scavenger receptor class B, t...

OBJECTIVES To delineate the role of capsaicin (8-methyl-N-vanillyl-6-nonenamide) as an inhibitor of the NorA efflux pump and its impact on invasion of macrophages by Staphylococcus aureus. METHODS Capsaicin in combination with ciprofloxacin was tested for activity against S. aureus SA-1199B (NorA overproducing), SA-1199 (wild-type) and SA-K1758 (norA knockout). The role of NorA in the intrace...

Ciprofloxacin is the substrate for a multidrug resistance-related protein (MRP)-like multidrug transporter in J774 mouse macrophages, which also modestly affects levofloxacin but only marginally affects garenoxacin and moxifloxacin (J.-M. Michot et al., Antimicrob. Agents Chemother. 49:2429-2437, 2005). Two clones of ciprofloxacin-resistant cells were obtained by a stepwise increase in drug con...

The ability of high density lipoproteins (HDL) to induce the clearance of cholesteryl esters from cultured cells has been explored. Studies using the J774 mouse macrophage cell line showed that these cells are not stimulated to clear esterified cholesterol upon exposure to HDL. This was observed over a wide range of HDL concentrations (10 to 1000 micrograms/ml HDL protein), and the lack of stim...

OBJECTIVE GX sPLA(2) potently hydrolyzes plasma membranes to generate lysophospholipids and free fatty acids; it has been implicated in inflammatory diseases, including atherosclerosis. To identify a novel role for group X (GX) secretory phospholipase A(2) (sPLA(2)) in modulating ATP binding casette transporter A1 (ABCA1) and ATP binding casette transporter G1 (ABCG1) expression and, therefore,...