Functional and quantitative changes of immune cells of ageing NZB mice treated with nandrolone decanoate. I. Effect on survival and autoantibody development.

We analysed the effect of nandrolone decanoate (ND) on functional and quantitative changes in immune cell populations, on survival, and on autoantibody production of female New Zealand Black (NZB) mice. Our results confirmed that, with increasing age, untreated NZB mice display a lower natural killer (NK) cell activity, an impaired T-cell function as evidenced by a reduced mitogen lymphoproliferative response, IL-2 production and generation of cytotoxic lymphocytes, a lower level of thymic serum factor (TSF), a reduced percentage of Thy-1+ cells; we also observed an increased incidence of mice with abnormally high levels of anti-DNA in the serum. In addition, we demonstrated an important defect in the IL-1 production by LPS-stimulated macrophages. ND administered to female NZB mice increased the survival time of the animals and reduced the anti-DNA titres. This favourable effect was associated with improved immune responses, especially those mediated by T cells; these included increased IL-2 production, complete recovery of cytotoxic T lymphocytes (CTL), a significant augmentation of the percentage of Lyt-2+ cells and enhanced TSF level. Moreover IL-1 production by macrophages returned to normal. These results suggest that ND acts on T-cell differentiation, either by a direct effect on thymic epithelial cells resulting in an increased TSF release, and/or via macrophage regulatory activity. The protective effect of ND may also be attributed in part to the higher number of Lyt-2+ (suppressor) T cells present in the spleen after treatment.