Thalidomide stimulates splenic IgM antibody response and cytotoxic T lymphocyte activity and alters leukocyte subpopulation numbers in female B6C3F1 mice

Thalidomide has been shown to have antiinflammatory and, more recently, imm unomodulating properties, which are beneficial for the treatment of an ever -increasing list of immune related diseases. Although considerable knowledg e regarding thalidomide's antiinflammatory properties has been acquired, re latively little is known about its immunomodulating properties in vivo. In this paper, a panel of immune assays was used to evaluate immunomodulation in female B6C3F1 mice treated intraperitoneally for 28 days with thalidomid e (30, 100, or 150 mg/kg/day). Spleen antibody forming cell response was si gnificantly enhanced by 37% in mice treated with 150 mg/kg/day, despite an 8% decrease in the percentage of Ig(+) B cells. A significant stimulatory t rend was observed for the cytotoxic T cell response across thalidomide trea tment groups. An evaluation of the spleen leukocyte subpopulations revealed a 23% increase in the absolute number of CD8+ T cells in the 150 mg/kg tre atment group and a 9 and 11% decrease in the absolute number of NK cells in both the 100 and 150 mg/kg thalidomide treatment groups, respectively. The se findings demonstrate that, in addition to modulating spleen leukocyte nu mbers, thalidomide also stimulates murine humoral and cellular immune respo nses in vivo. (C) 2000 Academic Press.