Decay-accelerating factor (Daf) dissociates C3/C5 convertases that assemble on host cells and thereby prevents complement activation on their surfaces. We demonstrate that during primary T cell activation, the absence of Daf on antigen-presenting cells (APCs) and on T cells enhances T cell proliferation and augments the induced frequency of effector cells. The effect is factor D- and, at least ...

Decay-accelerat ing factor (DAF), 1 which is an inhibi tor o f c o m p l e m e n t and is present on e ry th rocy te membranes , was first descr ibed by H o f f m a n n (1, 2) and later isolated and character ized as an Mr 70,000 prote in by Nicholson-Weller et al. (3). DAF very effectively prevents the amplif ication steps o f the cascade by in ter fer ing with assembly o f the C3-convertases,...

Although the cDNA of human decay accelerating factor (DAF) which restricts complement activation on homologous cell membranes was cloned in 1987, all trials to detect the cDNA of mouse DAF by cross-hybridization were unsuccessful. However, by immunoscreening with a rabbit antiserum against purified mouse DAF, we successfully cloned the cDNA. It contains four typical short consensus repeats (SCR...

Decay-accelerat ing factor (DAF), 1 which is an inhibi tor o f c o m p l e m e n t and is present on e ry th rocy te membranes , was first descr ibed by H o f f m a n n (1, 2) and later isolated and character ized as an Mr 70,000 prote in by Nicholson-Weller et al. (3). DAF very effectively prevents the amplif ication steps o f the cascade by in ter fer ing with assembly o f the C3-convertases,...

Molecular cloning of mouse decay accelerating factor (DAF; CD55) predicted two forms of the molecule, one transmembrane (TM) and the other glycosylphosphatidylinositol (GPI)-anchored; these are encoded by separate genes termed Daf-GPI and Daf-TM. In the present study several additional isoforms of mouse DAF, generated by alternative splicing from these genes, are described. Northern-blot analys...

Complement-mediated vascular injury is important in the pathophysiology of atherosclerosis and myocardial infarction. Because recent evidence shows that statins have beneficial effects on endothelial cell (EC) function independent of lipid lowering, we explored the hypothesis that statins modulate vascular EC resistance to complement through the upregulation of complement-inhibitory proteins. H...

The 791Tgp72 antigen has been used successfully as a target for tumor imaging and T-cell immunotherapy. We have characterized this antigen using the monoclonal antibody 791T/36 as a 72/66 kDa doublet. NH2-terminal protein sequencing of the two bands revealed identity with the complement regulatory protein CD55. Antibodies recognizing different domains of CD55 were also shown to bind to the puri...

X-ray microanalyses of sub-micrometer features require that a lower accelerating voltage be used. This reduction in the accelerating voltage reduces the penetrating distance of the beam electrons and thereby reduces the analytical volume. Two general strategies have been proposed for achieving the smallest analytical volume. The first approach involves significantly reducing the accelerating vo...

Decay-accelerating factor (DAF) mediates cellular attachment for many human picornaviruses. In most cases, viral binding to DAF is itself insufficient to permit cell infectivity, with a second, functional internalization receptor being required to facilitate this process. Previously, we postulated that the role of DAF in enterovirus cell infection is as a sequestration receptor, maintaining a r...