2e7a
From Proteopedia
TNF Receptor Subtype One-selective TNF Mutant with Antagonistic Activity
Structural highlights
Disease[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). Function[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.[1] The TNF intracellular domain (ICD) form induces IL12 production in dendritic cells.[2] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedTumor necrosis factor-alpha (TNF) induces inflammatory response predominantly through the TNF receptor-1 (TNFR1). Thus, blocking the binding of TNF to TNFR1 is an important strategy for the treatment of many inflammatory diseases, such as hepatitis and rheumatoid arthritis. In this study, we identified a TNFR1-selective antagonistic mutant TNF from a phage library displaying structural human TNF variants in which each one of the six amino acid residues at the receptor-binding site (amino acids at positions 84-89) was replaced with other amino acids. Consequently, a TNFR1-selective antagonistic mutant TNF (R1antTNF), containing mutations A84S, V85T, S86T, Y87H, Q88N, and T89Q, was isolated from the library. The R1antTNF did not activate TNFR1-mediated responses, although its affinity for the TNFR1 was almost similar to that of the human wild-type TNF (wtTNF). Additionally, the R1antTNF neutralized the TNFR1-mediated bioactivity of wtTNF without influencing its TNFR2-mediated bioactivity and inhibited hepatic injury in an experimental hepatitis model. To understand the mechanism underlying the antagonistic activity of R1antTNF, we analyzed this mutant using the surface plasmon resonance spectroscopy and x-ray crystallography. Kinetic association/dissociation parameters of the R1antTNF were higher than those of the wtTNF, indicating very fast bond dissociation. Furthermore, x-ray crystallographic analysis of R1antTNF suggested that the mutation Y87H changed the binding mode from the hydrophobic to the electrostatic interaction, which may be one of the reasons why R1antTNF behaved as an antagonist. Our studies demonstrate the feasibility of generating TNF receptor subtype-specific antagonist by extensive substitution of amino acids of the wild-type ligand protein. Creation and X-ray structure analysis of the tumor necrosis factor receptor-1-selective mutant of a tumor necrosis factor-alpha antagonist.,Shibata H, Yoshioka Y, Ohkawa A, Minowa K, Mukai Y, Abe Y, Taniai M, Nomura T, Kayamuro H, Nabeshi H, Sugita T, Imai S, Nagano K, Yoshikawa T, Fujita T, Nakagawa S, Yamamoto A, Ohta T, Hayakawa T, Mayumi T, Vandenabeele P, Aggarwal BB, Nakamura T, Yamagata Y, Tsunoda S, Kamada H, Tsutsumi Y J Biol Chem. 2008 Jan 11;283(2):998-1007. Epub 2007 Nov 14. PMID:18003610[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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