Immunochemical termination of self-tolerance

doi:10.1073/pnas.0804157105

Immunochemical termination of self-tolerance

Departments of *Chemistry,
^¶Immunology, and
^‖Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037; and
^§Genomics Institute of the Novartis Research Foundation, 10675 John Jay Hopkins Drive, San Diego, CA 92121

Contributed by Peter G. Schultz, April 29, 2008
↵^†J.G. and M.-L.T. contributed equally to this work. (received for review April 21, 2008)

Abstract

The ability to selectively induce a strong immune response against self-proteins, or increase the immunogenicity of specific epitopes in foreign antigens, would have a significant impact on the production of vaccines for cancer, protein-misfolding diseases, and infectious diseases. Here, we show that site-specific incorporation of an immunogenic unnatural amino acid into a protein of interest produces high-titer antibodies that cross-react with WT protein. Specifically, mutation of a single tyrosine residue (Tyr⁸⁶) of murine tumor necrosis factor-α (mTNF-α) to p-nitrophenylalanine (pNO₂Phe) induced a high-titer antibody response in mice, whereas no significant antibody response was observed for a Tyr⁸⁶ → Phe mutant. The antibodies generated against the pNO₂Phe are highly cross-reactive with native mTNF-α and protect mice against lipopolysaccharide (LPS)-induced death. This approach may provide a general method for inducing an antibody response to specific epitopes of self- and foreign antigens that lead to a neutralizing immune response.

Footnotes

**To whom correspondence may be addressed. E-mail: schultz{at}scripps.edu or rlerner{at}scripps.edu
Author contributions: J.G., M.-L.T., R.P., L.D., B.G.W., W.R., M.N., R.A.L., and P.G.S. designed research; J.G., M.-L.T., R.P., L.D., F.N., B.G.W., and D.M.K. performed research; J.G., M.-L.T., R.P., L.D., F.N., B.G.W., D.M.K., V.V.S., W.R., M.N., R.A.L., and P.G.S. analyzed data; and J.G., M.-L.T., V.V.S., and P.G.S. wrote the paper.
↵^‡Present address: School of Natural Sciences, University of California at Merced, P.O. Box 2039, Merced, CA 95344.
The authors declare no conflict of interest.
This article contains supporting information online at www.pnas.org/cgi/content/full/0804157105/DCSupplemental.