Plasma membrane-focused proteomics: dramatic changes in surface expression during the maturation of human dendritic cells.

The differential expression of surface molecules on dendritic cells (DC) reflects their functional differences as immature and mature subsets. It is difficult, however, to characterize differences in surface expression by standard proteomic approaches, due mainly to the hydrophobic nature and low abundance of the individual proteins in question. We have established a method for obtaining high-yield plasmalemma preparations which contain surface molecules enriched more than 200-fold by coating cells with beads conjugated with antibody against a cell type-specific cell-surface molecule, followed by nitrogen cavitated disruption, magnetic separation, and density gradient ultracentrifugation.

Plasmacytoid dendritic cells: from specific surface markers to specific cellular functions.

We have recently described a panel of monoclonal antibodies (mAb), that recognize two novel leukocyte surface antigens, BDCA-2 and BDCA-4. BDCA-2 is a novel type II C-type lectin specifically expressed by plasmacytoid dendritic cells (PDCs) that can internalize antigen for presentation to T cells. Furthermore, signaling via BDCA-2 may play a role in switching from interferon (IFN)-alpha/beta-controlled to interleukin (IL)-12-controlled immune response pathways, as triggering of BDCA-2 potently inhibits secretion of IFN-alpha/beta by PDCs and thereby promotes IL-12 p70 production in PDCs and other cells.

Difference between kidney and liver in decreased manganese superoxide dismutase activity caused by exposure of mice to mercuric chloride.

Dysfunction of antioxidant enzymes caused by mercuric compounds is partially associated with substantial induction of oxidative stress. In the present study, changes in renal and hepatic enzyme activity of an antioxidant protein manganese superoxide dismutase (Mn-SOD) after exposure to mercuric chloride (HgCl(2)) were examined in ICR mice. Subcutaneous administration of HgCl(2) (0.