TNF Receptor Subtype One-selective TNF Mutant with Antagonistic Activity; R1antTNF-T8
[TNFA_HUMAN] Genetic variations in TNF are a cause of susceptibility psoriatic arthritis (PSORAS) [MIM:607507]. PSORAS is an inflammatory, seronegative arthritis associated with psoriasis. It is a heterogeneous disorder ranging from a mild, non-destructive disease to a severe, progressive, erosive arthropathy. Five types of psoriatic arthritis have been defined: asymmetrical oligoarthritis characterized by primary involvement of the small joints of the fingers or toes; asymmetrical arthritis which involves the joints of the extremities; symmetrical polyarthritis characterized by a rheumatoidlike pattern that can involve hands, wrists, ankles, and feet; arthritis mutilans, which is a rare but deforming and destructive condition; arthritis of the sacroiliac joints and spine (psoriatic spondylitis).
[TNFA_HUMAN] Cytokine that binds to TNFRSF1A/TNFR1 and TNFRSF1B/TNFBR. It is mainly secreted by macrophages and can induce cell death of certain tumor cell lines. It is potent pyrogen causing fever by direct action or by stimulation of interleukin-1 secretion and is implicated in the induction of cachexia, Under certain conditions it can stimulate cell proliferation and induce cell differentiation. The TNF intracellular domain (ICD) form induces IL12 production in dendritic cells.
Publication Abstract from PubMed
Tumour necrosis factor (TNF) is an important cytokine that induces an inflammatory response predominantly through the TNF receptor-1 (TNFR1). A crucial strategy for the treatment of many autoimmune diseases, therefore, is to block the binding of TNF to TNFR1. We previously identified a TNFR1-selective antagonistic mutant TNF (R1antTNF) from a phage library containing six randomized amino acid residues at the receptor-binding site (amino acids 84-89). Two R1antTNFs, R1antTNF-T2 (A84S, V85T, S86T, Y87H, Q88N and T89Q) and R1antTNF-T8 (A84T, V85P, S86A, Y87I, Q88N and T89R), were successfully isolated from this library. Here, we analysed R1antTNF-T8 using surface plasmon resonance spectroscopy and X-ray crystallography to determine the mechanism underlying the antagonistic activity of R1antTNF. The kinetic association/dissociation parameters of R1antTNF-T8 were higher than those of wild-type TNF, indicating more rapid bond dissociation. X-ray crystallographic analysis suggested that the binding mode of the T89R mutation changed from a hydrophobic to an electrostatic interaction, which may be responsible for the antagonistic behaviour of R1antTNF. Knowledge of these structure-function relationships will facilitate the design of novel TNF inhibitors based on the cytokine structure.
Fast binding kinetics and conserved 3D structure underlie the antagonistic activity of mutant TNF: useful information for designing artificial proteo-antagonists.,Mukai Y, Nakamura T, Yoshioka Y, Shibata H, Abe Y, Nomura T, Taniai M, Ohta T, Nakagawa S, Tsunoda S, Kamada H, Yamagata Y, Tsutsumi Y J Biochem. 2009 Aug;146(2):167-72. Epub 2009 Apr 22. PMID:19386778
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.