It is well established that protein malnutrition (PM) impairs immune defenses and increases susceptibility to infection. Macrophages are cells that play a central role in innate immunity, constituting one of the first barriers against infections. Macrophages produce several soluble factors, including cytokines and growth factors, important to the immune response. Among those growth factors, gra...

Prostaglandin E2 (PGE2) is a lipid mediator that acts by ligating 4 distinct G protein–coupled receptors, E prostanoid (EP) 1 to 4. Previous studies identified the importance of PGE2 in regulating macrophage functions, but little is known about its effect on macrophage maturation. Macrophage maturation was studied in vitro in bone marrow cell cultures, and in vivo in a model of peritonitis. EP2...

Purified populations of both human peripheral blood monocytes and murine peritoneal macrophages synthesize and release Prostaglandin E in vitro. In contrast, prostaglandin E was detected in neither the supernate fluids from cultures of highly enriched human lymphocytes and granulocytes, nor in nonadherent murine peritoneal cells. Macrophage prostaglandin E production was markedly enhanced by en...

BACKGROUND/AIMS Peritoneal fibrosis is a serious complication of peritoneal dialysis (PD). It has been reported that administration of mizoribine, an effective immunosuppressant, ameliorated renal fibrosis in a rat model of unilateral ureteral obstruction. We therefore examined the effects of mizoribine in an experimental model of peritoneal fibrosis. METHODS 24 rats were given a daily intrap...

Two new indolocarbazole alkaloids, TAN-999 and TAN-1030A, were isolated from culture broths of Nocardiopsis dassonvillei C-71425 and Streptomyces sp. C-71799, respectively. Their structures were elucidated on the basis of their reactions, spectroscopic analyses and in particular, comparison of spectral data with that of staurosporine. These metabolites induced spreading of a murine macrophage c...

Chrysotile fibers injected into the peritoneal cavity of mice elicit a cellular exudate. Macrophages appearing in this exudate produce high levels of the neutral protease, plasminogen activator, when compared with the resident peritoneal macrophage population. In contrast, the levels of lysozyme and two lysosomal enzymes are the same for the two macrophage types. The asbestos-induced macrophage...

We showed previously that the calcineurin B subunit (CnB) plays an important role in activation of peritoneal macrophage, but the underlying mechanism remained unknown. To examine whether there is a CnB receptor on peritoneal macrophages, we performed the radioligand binding assay of receptors. The receptor saturation binding curve demonstrated high-affinity and specific binding; the maximum bi...

Sites of inflammation with prominent macrophage infiltration, such as wounds and certain tumors, are uniquely deficient in free arginine. The effects of arginine availability on macrophage physiology were investigated. When cultured in media containing less than 0.1 mM L-arginine, rat resident peritoneal macrophages exhibited enhanced spreading, tumor cytotoxicity, superoxide production, phagoc...

Prostaglandin E(2) (PGE(2)) is a lipid mediator that acts by ligating 4 distinct G protein-coupled receptors, E prostanoid (EP) 1 to 4. Previous studies identified the importance of PGE(2) in regulating macrophage functions, but little is known about its effect on macrophage maturation. Macrophage maturation was studied in vitro in bone marrow cell cultures, and in vivo in a model of peritoniti...

RATIONALE The role of sphingosine-1-phosphate (S1P) and its receptors in the pathogenesis of atherosclerosis has not been investigated. OBJECTIVE We hypothesized that the S1P receptor 3 (S1P(3)) plays a causal role in the pathogenesis of atherosclerosis. METHODS AND RESULTS We examined atherosclerotic lesion development in mice deficient for S1P(3) and apolipoprotein (Apo)E. Although S1P(3)...