Abstract
A human tumor necrosis factor (TNF) binding protein from serum of cancer patients was purified to homogeneity and partially sequenced. Synthetic DNA probes based on amino acid sequence information were used to isolate cDNA clones encoding a receptor for TNF. The TNF receptor (TNF-R) is a 415 amino acid polypeptide with a single membrane-spanning region. The extracellular cysteine-rich domain of the TNF-R is homologous to the nerve growth factor receptor and the B cell activation protein Bp50. Human embryonic kidney cells transfected with a TNF-R expression vector specifically bind both 125I-labeled and biotinylated TNF-α. Unlabeled TNF-α and TNF-β were equally effective at displacing the binding of labeled TNF-α to TNF-R expressing cells. Northern analysis indicates a single species of mRNA for the TNF-R in a variety of cell types. Therefore, the soluble TNF binding protein found in human serum is probably proteolytically derived from the TNF-R.
Highlights
Tumor necrosis factor-alpha (TNF-a) is a multipotent cytokine produced mainly by activated macrophages
Purification and Characterization of tumor necrosis factor (TNF) BP A protein that inhibits the activity of both TNF-a and TNF-13 has been detected in the serum of cancer patients but not healthy individuals (Gatanaga et al, 1990)
Proteins eluted from the TNF-a affinity column were separated by reverse-phase HPLC, and several residues of N-terminal amino acid sequence were determined for each
Summary
A human tumor necrosis factor (TNF) binding protein from serum of cancer patients was purified to homogeneity and partially sequenced. Synthetic DNA probes based on amino acid sequence information were used to isolate cDNA clones encoding a receptor for TNF. The TNF receptor (TNF-R) is a 415 amino acid polypeptide with a single membrane-spanning region. The extracellular cysteine-rich domain of the TNF-R is homologous to the nerve growth factor receptor and the B cell activation protein Bp50. Human embryonic kidney cells transfected with a TNF-R expression vector bind both 125I-labeled and biotinylated TNF-a. Unlabeled TNF-a and TNF-f3 were effective at displacing the binding of labeled TNF-a to TNF-R expressing cells. The soluble TNF binding protein found in human serum is probably proteolytically derived from the TNF-R
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
