Michael G. Mage, D. D. S.

Laboratory of Biochemistry, Division of Basic Sciences, National Cancer Institute, National Institutes of Health

Building 37, Room 4C28
37 CONVENT DR MSC 4255
BETHESDA MD 20892-4255

Phone: 301-496-1249
Fax: 301-402-3095

xgm@cu.nih.gov

Biography:

Dr. Mage received his postdoctoral training at Columbia University, studying affinity purification and properties of antihapten antibodies with Stuart Tanenbaum and Sam Beiser. He came to the NIH. in 1962, where he has studied antibody structure, and pioneered what are now standard affinity-based cell separation methods. With his immunology group, he studies T cell immunity to recombinant MHC molecules. A holder of the Public Health Service commendation medal, his NCI home since 1966 has been the Laboratory of Biochemistry.


Research:

T cell responses to infections, neoplasms, and autoantigens require degradation of antigenic proteins and display of antigenic peptides by MHC molecules on the surface of antigen-presenting cells. For HIV infections, there is evidence that certain T cell responses, of the TH1 type, in the absence of antibody formation, may be highly protective, while others, of the TH2 type, may interfere. In other infections, the reverse may be true. Certain peptides, due to their effective concentration, relative affinity for MHC molecules, or to the T cell repertoire, may dominate a T cell response at the expense of other peptides. Whole organism, protein, or peptide vaccines rely on the cellular machinery to cut out and bind peptides to endogenous MHC molecules, so investigators have limited control over which peptides will be presented by which MHC molecules to the T cells. Our group seeks to circumvent such problems by development of peptide-MHC molecular vaccines. We prepare recombinant genes that encode single chain MHC molecules with covalently attached antigenic peptides (MHCP). Following the engineering by Dr. Li Lee of a recombinant single chain human Class I MHC (HLA-A2.1) molecule with a viral peptide from HTLV1 covalently attached, Dr. Xiaojie Zhu has engineered recombinant single chain human class II (HLA-DR1) MHCP with covalently attached peptides (from influenza HA or from HIV gag). In these molecules the entire heterotrimer of peptide, beta chain, and alpha chain is expressed as a single covalently linked polypeptide chain. These recombinant MHCP are expressed on the surface of transfected cells. They stimulate normal human lymphocytes and the appropriate T cell clones.

Recombinant MHC molecules may also be useful for studying the cell biology of T cell stimulation. Dr. Zhu has prepared covalently linked Class II MHCP as "superdimers" and "supertrimers" to study the role of valency in TCR signal transduction. We are also preparing such molecules with antagonist, agonist, and mixed peptides to study peptide antagonism at the level of the MHCP-TCR interaction. Such soluble molecules, used in the absence of costimulators or Fc receptors may be useful as T cell toleragens. They are being evaluated for use in ex-vivo T cell expansion in collaboration with Carl June and Katya Schlienger of the Naval Medical Research Institute. We are preparing variants of these molecules for collaborative studies with Ettore Appella, M.D.,of NCI, and Bill Biddison, Roland Martin, and Bernard Hemmer of NINDS. In collaboration with David Margulies, M.D., Ph.D., National Institute of Allergy and Infectious Diseases,, we are also using single chain MHC Class I molecules as transgenes to study selection and expansion of the T cell repertoire. We are interested in collaborating with investigators who wish to explore covalent MHCP as immunogens and tolerogens.


Recent Publications:

  1. Lee L, McHugh L, Ribaudo RK, Kozlowski S, Margulies DH and Mage MG. Functional cell surface expression by a recombinant single chain class I MHC molecule with a cis active b2 microglobulin domain. Eur J Immunol 1994; 24: 2633-2639.
  2. Lee L, McHugh L, Sakuma S, Loftus D, Appella E, Margulies DH, Mage M. Peptide loaded recombinant single chain HLA molecules as potential immunogens for T cells. In Brown F, Chanock R, Ginsburg HS, Norrby E (Eds.): Vaccines 95. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY 1995, pp. 243-247.
  3. Grohmann U, Puccetti P, Belladonna ML, Fallarino F, Bianchi R, Binaglia L, Sagakuchi K, Mage MG, Appella E, Fioretti MC. Multiple point mutations in an endogenous retroviral gene confer high immunogenicity on a drug-treated murine tumor. J Immunol. 1995; 154:4630-4641.
  4. Lee L, Loftus D, Appella E, Margulies DH, Mage M. A recombinant single chain HLA-A2.1 molecule, with a cis active beta-2-microglobulin domain, is biologically active in peptide binding and antigen presentation. Human Immunol 1996; 49: 28-37.
  5. Zhu X, Bavari S, Ulrich R, Sadegh-Nasseri S, Ferrone S, McHugh L, and Mage M. A recombinant single chain human Class II MHC molecule (HLA-DR1) as a covalently linked heterotrimer of alpha chain, beta chain, and antigenic peptide, with immunogenicity in vitro and reduced affinity for bacterial superantigens. Eur J Immunol 1997;27:1933-1997.
  6. Plaksin D, Polakova K, Mage MG, Margulies DH. Rigidification of the Alpha 2 helix of an MHC Class I molecule by a valine to proline mutation in position 165 does not prevent peptide specific antigen presentation. J Immunol 1997;159:4408-4414.


Last revised on July 2, 1998, by Beverly Miller


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