Regulation of the macrophage receptor for modified low density lipoprotein (LDL) was evaluated using human monocyte-derived macrophages and acetyl LDL. Factors that regulate native LDL receptor activity in other cell types, such as the cholesterol content of the incubation medium, insulin, and platelet-derived growth factor had no effect on acetyl LDL degradation. Conditioned medium from mature...

To facilitate in vitro studies of the immunology of human leishmaniasis, we developed a method of growing pathogenic Leishmania in human monocyte-derived macrophages. After 6 days of incubation, adherent mononuclear cells were infected with Leishmania donovani amastigotes obtained from infected hamster spleen cells or with L. tropica amastigotes obtained from infected BALB/c tissue mouse footpa...

Peritoneal macrophages are one of the most studied macrophage populations in the body, yet the composition, developmental origin and mechanisms governing the maintenance of this compartment are controversial. Here we show resident F4/80(hi)GATA6(+) macrophages are long-lived, undergo non-stochastic self-renewal and retain cells of embryonic origin for at least 4 months in mice. However, Ly6C(+)...

Using in vitro culture systems. we have studied the effect of coincubating human monocyte-macrophages with autologous T lymphocytes on colony-stimulating activity (CSA) elaboration in response to methanol extraction residue (MER) of BCG. When monocyte-macrophages were coincubated with T lymphocytes for 4 days at a ratio of 1 :3. the resultant colony-stimulating activity. assayed against light d...

BACKGROUND HIV-1 infected macrophages play an important role in rendering resting T cells permissive for infection, in spreading HIV-1 to T cells, and in the pathogenesis of AIDS dementia. During highly active anti-retroviral treatment (HAART), macrophages keep producing virus because tissue penetration of antiretrovirals is suboptimal and the efficacy of some is reduced. Thus, to cure HIV-1 in...

Abstract Myeloid cells are an important player in the immune system, and form first line of defense against pathogens, such as Mycobacterium tuberculosis (Mtb), causative pathogen for (TB) disease. They include macrophages, a target Mtbinfection, dendritic (DCs), which present Mtb-derived antigens to prime activate T cells. In order investigate myeloid-specific host factors involved response we...

Inflammation is associated with macrophage activation, and this process has been shown to occur during atherogenesis. Macrophages (J774A.1) that were activated with either lipopolysaccharide (LPS), zymosan, or phorbol ester demonstrated a 30-35% increased uptake and degradation of low density lipoprotein (LDL) in comparison with nonactivated cells. This phenomenon was also shown for LDL cellula...

Recent reports have suggested that long-term administration of erythromycin (EM) appears to ameliorate some of chronic inflammatory processes where macrophages and lymphocytes play important roles. Our study was initiated to examine the effect of EM on monocyte-macrophage lineage in vitro. EM (1 approximately 100 micrograms/ml) significantly increased the number of adherent monocyte-derived mac...

Chlamydia pneumoniae has recently been associated with atherosclerotic lesions in coronary arteries. To investigate the biological basis for the dissemination and proliferation of this organism in such lesions, the in vitro growth of C. pneumoniae was studied in two macrophage cell lines, peripheral blood monocyte-derived macrophages, human bronchoalveolar lavage macrophages, several endothelia...