We have prepared an mAb specific for a human cell surface component (termed anti-Fas mAb). Anti-Fas shows cell-killing activity that is indistinguishable from the cytolytic activity of TNF. Fas antigen was characterized by western blotting, indicating that Fas antigen is a cell surface protein with a molecular weight of 200,000, which is different from the molecular weight of TNF-R. Fas antigen, however, is co-downregulated with the TNF-R when cells sensitive to the cytolytic activity of TNF are incubated with either TNF or anti-Fas. In contrast, Fas antigen on cells insensitive to TNF is not co-downregulated with the TNF-R. We suggest that the cell-killing activity of TNF is mediated by Fas antigen associated with the TNF-R.

https://rupress.org/jem/article-pdf/169/5/1747/1099140/1747.pdf

A cell-killing monoclonal antibody (anti-Fas) to a cell surface antigen co-downregulated with the receptor of tumor necrosis factor

Epidermal growth factor-receptor-protein kinase interactions. Co-purification of receptor and epidermal growth factor-enhanced phosphorylation activity.

A native 170,000 epidermal growth factor receptor-kinase complex from shed plasma membrane vesicles.

https://www.cell.com/cell/pdf/0092-8674(91)90411-Q.pdf

Characterization of two 85 kd proteins that associate with receptor tyrosine kinases, middle-T/pp60c-src complexes, and PI3-kinase.

https://www.jbc.org/content/259/4/2553.full.pdf

C-kinase phosphorylates the epidermal growth factor receptor and reduces its epidermal growth factor-stimulated tyrosine protein kinase activity.

1. A method was developed which allows the rapid preparation of pure plasma membranes in high yield from cultured fibroblasts. 2. Cells are lysed in hypo-osmotic borate/EDTA and, after differential centrifugation, the membranes collected by centrifugation on a sucrose barrier. 3. Electron microscopy of the isolated material shows large membrane vesicles essentially free from contaminating organelles. 4. There is no detectable activity of the endoplasmic-reticulum enzyme marker, NADH2--lipoamide oxidoreductase (EC 1.6.4.3), and that of succinate dehydrogenase (EC 1.3.99.1), a marker for mitochondria, is substantially decreased. Chemical compositions are in good agreement with previous observations. 5. This study confirms the usefulness of applied isotopic markers for isolating plasma membranes.

/pdf/rapid-isolation-of-plasma-membranes-in-high-yield-from-samx41t031.pdf

D Thom

Papers

Rapid isolation of plasma membranes in high yield from cultured fibroblasts.

Glycoproteins in the recognition of substratum by cultured fobroblasts.