PRLr and PRL expression in monocytes isolated from peripheral mononuclear cells (PBMC) of healthy donors. Monocytes isolated from PBMC of different healthy male subjects were tested by Western blot analysis after activation with LPS 1 μg/ml for 8 h: A, PRLr; and B, PRL. Total extract proteins of the breast cancer cells (MCF-7) or human recombinant PRL (hrPRL) were used as positive controls. β-Actin expression was revealed as endogenous control and graphs show densitometry analyses. Experiments were performed in triplicate. Data are expressed as mean ± SD, and significance is defined as p<0.05*, p<0.01**; p<0.001*** versus control.