April 12, 2000

Molecular Researcher of Killer- and T-Cells Honored

BALTIMORE, Md.--Biochemist Roy Mariuzza, who recently identified a lock and key complex of natural killer cells in the blood stream for the first time, has received a University System of Maryland (USM) Board of Regent's Faculty Award.

The research professor with the University of Maryland Biotechnology Institute (UMBI) was recognized at a ceremony on April 7 for his groundbreaking research and education in understanding immune-system receptors, a branch of molecular science that is critically important to advancing medical treatments.

"The first real look" at the subtle workings of natural killer (NK) cells -- how they recognize abnormal cells and destroy them -- was reported by Mariuzza and collaborators at the National Institutes of Health in the November 9, 1999 issue of the journal Nature. NK cells are a primitive, first line of defense against cancer tumor cells and cells infected with the AIDS virus and other harmful microbes.

The molecular machinery of NK cells is not as well understood as that of T or B white blood cells for fighting infections, but is also essential for maintaining health, says Mariuzza, who is with UMBI's Center for Advanced Research in Biotechnology (CARB) in Rockville, Md.

In 1995, Mariuzza described in the journal Science the first three-dimensional structure of a specific chain of a T cell-antigen receptor (TCR). Recognized widely as a major breakthrough, the achievement allowed immunologists to visualize directly how the body recognizes foreign proteins and starts immune responses by the TCR. Mariuzza's work has contributed to the understanding of a unique class of T cells that defend against diseases such as tuberculosis.

Mariuzza was honored with twelve other USM faculty recipients of the award at the meeting of the Board of Regents.

"These faculty members, recommended by the Regents' Faculty Award Committee, represent the ideal in areas essential to the mission of higher education," says Nathan A. Chapman, Jr., chairman of the board. "They have demonstrated a high level of dedication to their craft, and the Board is pleased to bestow its highest honor upon them." Mariuzza's award also recognizes his part in the education of many postdoctoral students, training them in molecular biology, protein chemistry, and x-ray crystallography, says Chapman.

Mariuzza says his current work on NK cells will "give us a basis for expanding research on NK cell receptors. We have found two distinct (molecular) binding sites where they attach and monitor cells. Now we need to compare this to still unknown structures of other NK receptors to find out how each of them works."

Scientists estimate that NK cells make up five to 16 percent of the total number of white blood cells that the body uses to fight infections. People with defective or absent NK cell activity can contract a wide spectrum of diseases, particularly cancers. In fact, results from a number of clinical trials indicate that NK cells can be used to control tumor metastases, or the spread throughout the body. The therapeutic uses of NK cell activity will likely increase as their relationships to healthy and diseased cells becomes better known, says Mariuzza.

He is focusing on unraveling the structural basis of autoimmune diseases, especially multiple sclerosis. Immunologists and the general science community have widely recognized Mariuzza's contributions, with numerous publications in leading journals, commentaries by journal editors, and to illustrations on covers of several journals.