Disease relevance of Mmd

• This increased pool of cells in the macrophage/osteoclast lineage can be functionally upregulated with the subsequent addition of DBP-MAF to perform the activities of phagocytosis and bone resorption [1].
• The MAF rendered macrophages from normal C57BL/6 mice cytotoxic against the syngeneic B16 melanoma and the allogeneic AC 15091 [2].
• In the present study, the ability of lymphokines (MAF and IFN gamma) and microbial agents (CP and LM) to induce and maintain tumoricidal activity in BMMP in vitro and to enhance local resistance to the DA rat D-12 ascites tumor in vivo was assessed comparatively [3].
• These data suggest that DBP-MAF and the synthetic peptide represent therapeutic opportunities for the treatment of a number of bone diseases and skeletal disorders [4].
• Vitamin D-binding protein-macrophage activating factor (DBP-MAF) has previously been shown to stimulate bone resorption and correct the skeletal defects associated with osteopetrosis in two nonallelic mutations in rats [4].

High impact information on Mmd

• Incubation of 24/G1 supernatants diluted to 8.3 IRU IFN-gamma/ml with 6 X 10(6) elicited peritoneal macrophages or bone marrow-derived macrophages for 4 h at 37 degrees C, resulted in removal of 80% of the MAF activity from the lymphokine preparation [5].
• Although the majority of murine cell lines tested absorbed 24/G1 MAF activity, two murine macrophage cell lines, P388D1 and J774, were identified which absorbed significantly reduced amounts of natural IFN-gamma [5].
• To study the effects of these compounds on the macrophage/osteoclast precursors, DBP-MAF, CSF-1, and the combination of these compounds were given to newborn ia and normal littermate animals [1].
• Two compounds, colony-stimulating factor-1 (CSF-1) and vitamin D-binding protein-macrophage activating factor (DBP-MAF) were used in the present study to evaluate their effects on the peritoneal population of cells and on cells within the bone marrow microenvironment in normal and incisors absent (ia) osteopetrotic rats [1].
• Both Jun and Maf bind to this element and activate the gene having this element, but only Jun-activated expression was specifically inhibited by PPAR alpha [6].

Chemical compound and disease context of Mmd

• In contrast, the four AM fractions were equally susceptible to activation stimuli, such as lipopolysaccharide (LPS), Nocardia rubra cell wall skeleton (N-CWS), macrophage activating factor (MAF), muramyl dipeptide (MDP), or a mixture of MAF and MDP in vitro to become cytotoxic to syngeneic mammary adenocarcinoma cells [7].

Biological context of Mmd

• We here show that the transactivation potential of c-Maf and MafB for the rat gammaD-crystallin Maf-responsive element (gammaD MARE) is dependent upon the cellular context and, using chimeric and single domain mutants, that c-Maf is most likely to be the cognate factor for the gammaD MARE in the lens [8].
• Since treatment of MAF and MDP with polymyxin B did not interfere with macrophage activation, we were able to rule out the possibility that our preparations were contaminated with lipopolysaccharide [9].
• The data thus demonstrated that MAF can cross strain and even species specificities and can activate macrophages to kill tumors in a nonspecific manner [10].
• IPA and MAF were not produced with the same kinetics and in the same T cell concentration conditions as IL 2 and TRF [11].
• After 2 weeks of treatment with either the whole protein (DBP-MAF) or the small peptide, bone density was significantly increased in the treated animals compared to the saline controls [4].

Anatomical context of Mmd

• Here we report on the identification of the macrophage/microglia activation factor (MAF), a new membrane protein with seven putative transmembrane domains [12].
• In conclusion, these results imply that MAF is involved in the dynamics of lysosomal membranes associated with microglial activation following brain lesion [12].
• Furthermore, MAF-transfected cells show that MAF is primarily associated with late endosomes/lysosomes, and that this association can be disrupted by activation of protein kinase C-dependent pathways [12].
• Identification of macrophage/microglia activation factor (MAF) associated with late endosomes/lysosomes in microglial cells [12].
• Previous studies in this laboratory have demonstrated that administration of DBP-MAF to newborn ia animals results in a substantial increase in bone marrow cavity size due to upregulated osteoclast function [1].

Associations of Mmd with chemical compounds

• Normal macrophages from C57BL/6, C3H/Hen, and C57BL/6 X C3H F1 mice treated with liposome-encapsulated MAF exhibited significant in vitro cytotoxicity against syngeneic and allogeneic tumor cells but did not kill nontumorigenic normal cells [13].
• Alveolar macrophages (AM) from lungs of normal F344 rats can be rendered tumoricidal by incubation in vitro with either muramyl dipeptide (MDP) at a minimum dose of 10 micrograms/ml or undiluted cell-free culture supernatants from mitogen-stimulated F344 rat lymphocytes rich in macrophage-activating factor (MAF) activity [9].
• These results suggest that pyridoxine deficiency affects not only phagocytic function of AM responsible for host defense in the lung but also MAF production by splenic cells [14].
• Functional changes of AM were determined by measuring phagocytosis of latex beads, yeast cells or opsonized sheep red blood cells (SRBC) and the ability to respond to a macrophage-activating factor (MAF) such as lymphokines [15].
• Upon removal of its sialic acid or galactose residue, vitamin D-binding protein (DBP) becomes a potent macrophage-activating factor, DBP-MAF [16].

Other interactions of Mmd

• Dominant-negative mutants of Nrf2 and Maf, but not of c-Fos and c-Jun, inhibited basal and heme-induced expression of an E1-controlled luciferase gene [17].

Analytical, diagnostic and therapeutic context of Mmd

• Furthermore, the production of macrophage-activating factor (MAF) from rat splenocytes was higher in arginine-rich group than that of control group [18].

References