EDWIN L. THOMAS
PROFESSOR

EDUCATION:
B.A. 1965, Miami University, Oxford, Ohio
M.S. 1966, The University of Michigan, Ann Arbor, Michigan
Ph.D. 1970, The University of Michigan, Ann Arbor, Michigan

RESEARCH INTERESTS: Individual cells and complex organisms simultaneously carry out processes that are competing or mutually inhibitory such as synthesis and degradation, oxidation and reduction. Incompatible processes are confined in separate compartments and regulated by controlling the movement of materials from one compartment to another. Each cell is a compartment defined by a membrane that limits the movement of water-soluble substances to specific transport channels. Groups of cells create semi-permeable barriers in the body, and within each cell there are separate membrane-bounded compartments with specific functions. Human leukocytes provide a striking example of the use of compartmentation to separate incompatible processes. These cells protect against infection by ingesting and killing invading microorganisms within compartments called phagolysosomes. Proteins that have the ability to bind to cell membranes and kill cells are stored in leukocyte secretory granules and released into phagolysosomes. Toxic oxidizing agents are also produced by leukocytes at the inner surface of the phagolysosome membrane. We are identifying and characterizing the toxic proteins and oxidizing agents and studying the processes that confine toxicity and prevent damage to leukocytes and the tissues. Principal areas of study at present are the peroxidase enzymes of leukocytes and the role of superoxide, nitric oxide, and other free-radicals in leukocyte function.

CURRENT RESEARCH SUPPORT:
Alumni Endowment Fund, College of Dentistry, University of Tennessee, Memphis "Resistance of Oral Bacteria to Antibiotic Peptides of Human Leukocytes" September 1, 1995 - August 31, 1997; $8,400 in TDC

GRADUATE STUDENTS:
Thomas M. Aune, Ph.D., 1978; Charles C. King (current student)

PUBLICATIONS: (Only those publications since 1985 are listed):
34. Thomas, E.L., Grisham, M.B., Melton, D.F., and Jefferson, M.M. (1985) Evidence for a role of taurine in the in vitro oxidative toxicity of neutrophils toward erythrocytes. J. Biol. Chem., 260, 3321-3329.
35. Thomas, E.L. (1985) Products of lactoperoxidase-catalyzed oxidation of thiocyanate and halides. In K.M. Pruitt and J.O. Tenovuo (Eds.), The Lactoperoxidase System, Chemistry and Biological Significance (pp. 31-53). New York: Marcel Dekker.
36. Thomas, E.L. (1985) Bacterial hydrogen peroxide production. In K.M. Pruitt and J.O. Tenovuo (Eds.), The Lactoperoxidase System, Chemistry and Biological Significance. (pp. 179-202). New York: Marcel Dekker.
37. Thomas, E.L. and Fishman, M. (1986) Oxidation of chloride and thiocyanate by isolated leukocytes. J. Biol. Chem., 261, 9694-9702.
38. Thomas, E.L., Grisham, M.B., and Jefferson, M.M. (1986) Preparation and characterization of chloramines. In G. DiSabato and J. Everse (Eds.), Methods in Enzymology; Phagocytosis and Cell-Mediated Cytotoxicity, Vol. 132. (pp. 569-585). Orlando, Florida: Academic Press.
39. Thomas, E.L., Grisham, M.B., and Jefferson, M.M. (1986) Cytotoxicity of chloramines. In G. DiSabato and J. Everse (Eds.), Methods in Enzymology; Phagocytosis and Cell-Mediated Cytotoxicity, Vol. 132. (pp. 585-593). Orlando, Florida: Academic Press.
40. Thomas, E.L., Jefferson, M.M., Bennett, J.J., and Learn, D.B. (1987) Mutagenic activity of chloramines. Mutation Res., 188, 35-43.
41. Thomas, E.L. (1987) Role of neutrophils in inflammatory tissue injury. In J.R.J. Sorenson (Ed.), Biology of Copper Complexes. (pp. 187-196). Clifton, New Jersey: Humana Press.
42. Thomas, E.L., Learn, D.B., Jefferson, M.M., and Weatherred, W. (1988) Superoxide-dependent oxidation of extracellular reducing agents by isolated neutrophils. J. Biol. Chem., 263, 2178-2186.
43. Learn, D.B. and Thomas, E.L. (1988) Inhibition of tumor cell glutamine uptake by isolated neutrophils. J. Clin. Invest., 82, 789-796.
44. Thomas, E.L., Lehrer, R.I., and Rest, R.F. (1988) Human neutrophil antimicrobial activity. Rev. Infect. Dis., 10, S450-S456.
45. Bozeman, P.M., Learn, D.B., and Thomas, E.L. (1990) Assay of the human leukocyte enzymes myeloperoxidase and eosinophil peroxidase. J. Immunol. Methods, 126, 125-133.
46. Learn, D.B., Fried, V.A., and Thomas, E.L. (1990) Taurine and hypotaurine content of human leukocytes. J. Leukocyte Biol. , 48, 174-182.
47. Thomas, E.L. and Learn, D.B. (1991) Myeloperoxidase-catalyzed oxidation of chloride and other halides: The role of chloramines. In J. Everse and M.B. Grisham (Eds.), Peroxidases: Chemistry and Biology, Vol. 1 (pp. 83-104) Boca Raton, Florida: CRC Press.
48. Thomas, E.L., Bozeman, P.B., and Learn, D.B. (1991) Lactoperoxidase: Structure and catalytic properties. In J. Everse and M.B. Grisham (Eds.), Peroxidases: Chemistry and Biology , Vol. 1. (pp. 123-142). Boca Raton, Florida: CRC Press.
49. Bozeman, P.M., Learn, D.B., and Thomas E.L. (1992) Inhibition of the human leukocyte enzymes myeloperoxidase by dapsone. Biochem. Pharmacol., 44, 553-563.
50. Thomas, E.L., Jefferson, M.M., Joyner, R.E., Cook, G.S., and King, C.C. (1994) Leukocyte myeloperoxidase and salivary lactoperoxidase: Identification and quantitation in human mixed saliva. J. Dent. Res., 73, 544-555.
51. Thomas, E.L., Milligan, T.W., Joyner, R.E., and Jefferson, M.M. (1994) Antibacterial activity of hydrogen peroxide and the lactoperoxidase-hydrogen peroxide-thiocyanate system against oral streptococci. Infect. Immun., 62, 529-535.
52.Thomas, E.L., Bozeman, P.M., Jefferson, M.M., and King, C.C. (1995) Oxidation of bromide by the human leukocyte enzymes myeloperoxidase and eosinophil peroxidase: Formation of bromamines. J. Biol. Chem., 270, 2906-2913.