Determination of Cellular Lipids Bound to Human CD1d Molecules

CD1 molecules are glycoproteins that present lipid antigens at the cell surface for immunological recognition by specialized populations of T lymphocytes. Prior experimental data suggest a wide variety of lipid species can bind to CD1 molecules, but little is known about the characteristics of cellular ligands that are selected for presentation. Here we have molecularly characterized lipids bound to the human CD1d isoform. Ligands were eluted from secreted CD1d molecules and separated by normal phase HPLC, then characterized by mass spectroscopy. A total of 177 lipid species were molecularly identified, comprising glycerophospholipids and sphingolipids. The glycerophospholipids included common diacylglycerol species, reduced forms known as plasmalogens, lyso-phospholipids (monoacyl species), and cardiolipins (tetraacyl species). The sphingolipids included sphingomyelins and glycosylated forms, such as the ganglioside GM3. These results demonstrate that human CD1d molecules bind a surprising diversity of lipid structures within the secretory pathway, including compounds that have been reported to play roles in cancer, autoimmune diseases, lipid signaling, and cell death

A Review of Strategic Process Research

This article reviews research on the process of strategic management reported over the last six years in seven leading journals. Nine "streams" of work are identified and critiqued. The field is described as giving continuing attention to the possibilities and problems of strategic planning and decision making, but also moving into new areas of research - especially the problem of how the attention of decision makers is directed toward specific agendas for action. We recommend more studies that simultaneously consider strategy formulation and implementation and more studies that attempt to integrate methods and concerns across the various areas of process research. Finally, we recommend that future research give simultaneous attention to the content as well as the process of strategy