Abstract |
The cytokine lymphotoxin-α (LTα) is a promising candidate for use in cancer therapy. However, the instability of LTαin vivo and the insufficient levels of tumor necrosis factor receptor 1 (TNFR1)-mediated bioactivity of LTα limit its therapeutic potential. Here, we created LTα mutants with increased TNFR1-mediated bioactivity by using a phage display technique. We constructed a phage library displaying lysine-deficient structural variants of LTα with randomized amino acid residues. After affinity panning, we screened three clones of lysine-deficient LTα mutant, and identified a LTα mutant with TNFR1-mediated bioactivity that was 32 times that of the wild-type LTα (wtLTα). When compared with wtLTα, the selected clone showed augmented affinity to TNFR1 due to slow dissociation rather than rapid association. In contrast, the mutant showed only 4 times the TNFR2-mediated activity of wtLTα. In addition, the LTα mutant strongly and rapidly activated caspases that induce TNFR1-mediated cell death, whereas the mutant and wtLTα activated nuclear factor-kappa B to a similar extent. Our data suggest that the kinetics of LTα binding to TNFR1 play an important role in signal transduction patterns, and a TNFR1-selective LTα mutant with augmented bioactivity would be a superior candidate for cancer therapy.
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Authors | Tomohiro Morishige, Yasuo Yoshioka, Shogo Narimatsu, Shinji Ikemizu, Shin-ichi Tsunoda, Yasuo Tsutsumi, Yohei Mukai, Naoki Okada, Shinsaku Nakagawa |
Journal | Cytokine
(Cytokine)
Vol. 61
Issue 2
Pg. 578-84
(Feb 2013)
ISSN: 1096-0023 [Electronic] England |
PMID | 23246116
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Copyright | Copyright © 2012 Elsevier Ltd. All rights reserved. |
Chemical References |
- Lymphotoxin-alpha
- Mutant Proteins
- NF-kappa B
- Receptors, Tumor Necrosis Factor, Type I
- Caspases
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Topics |
- Amino Acid Sequence
- Caspases
(metabolism)
- Cell Death
(drug effects)
- Cell Line, Tumor
- Electron Spin Resonance Spectroscopy
- Enzyme Activation
(drug effects)
- Humans
- Isoelectric Point
- Kinetics
- Lymphotoxin-alpha
(chemistry, pharmacology, therapeutic use)
- Models, Molecular
- Molecular Sequence Data
- Mutant Proteins
(chemistry, pharmacology, therapeutic use)
- NF-kappa B
(metabolism)
- Neoplasms
(drug therapy, enzymology, pathology)
- Protein Binding
(drug effects)
- Receptors, Tumor Necrosis Factor, Type I
(chemistry, metabolism)
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