Collaborators include scientists from Roswell Park Cancer Institute, Buffalo, N.Y.; the Tumor Immunity and Tolerance Section of the Laboratory of Molecular Immunoregulation, National Cancer Institute; and Howard Hughes Medical Institute/Memorial Sloan-Kettering Cancer Center.

"What we are showing is that testosterone seems to impede immunity," says Eugene Kwon, M.D., the Mayo Clinic urologist and immunology researcher who led the research team. "However, when testosterone is withdrawn, you get an increased host immune response indicated by the rising numbers of immune cells that are available to participate."

T-lymphocytes are cells that are vital to controlling the body's immune response. "T cells," as they are usually called by scientists, are white blood cells that can fight against tumor cells and infection. Alternatively, T cells can help other immune cells known as "B cells" make antibodies to defend the body against certain bacterial and fungal infections, and possibly against cancer. The research findings may have broad potential applications to public health. For example, knowing that testosterone levels affect T-cell response may help:

* explain why women are more prone than men to develop "autoimmune disease."

* speed the development of drugs that bolster the immune system to treat such immune-deficiency diseases as AIDS.

* improve vaccines.

* decrease the time needed to reconstitute the immune system after bone marrow transplantation.

* protect cancer patients who are receiving immunotherapy treatments or w
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Contact: Bob Nellis
newsbureau@mayo.edu
507-284-5005
Mayo Clinic
5-Nov-2004