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Biomedical subjects

R Di Eugenio

Publications and source records attributed to R Di Eugenio.

6 recordsLinked to original sources
PubMed1989

Effects of cadmium on lymphocyte activation.

The effects of cadmium (Cd) on phytohemoagglutinin or phorbol myristate acetate-induced lymphocyte activation were investigated and a dose-dependent inhibition of cell proliferation was found. Kinetic studies revealed that the Cd-sensitive step is an early event of T cell stimulation. Failure of IL2 secretion and reduction of IL2 receptor expression in the Cd-treated cells are also reported. Regardless of which mechanism is responsible for Cd effects, our studies show that the inhibition of lymphocyte activation is associated with reduced [3H]phorbol dibutyrate binding to Ca2+-phospholipid-dependent protein kinase and altered breakdown of phosphatidylinositols. Thus, Cd interferes with two biochemical events which play a critical role in lymphocyte signal transduction and activation.

Adult↗
PubMedDate not supplied

In vivo cadmium treatment alters natural killer activity and large granular lymphocyte number in the rat.

The effects of oral exposure for nearly 6 months to Cd (200 or 400 ppm) on rat natural killer (NK) activity were investigated. No significant differences in body and thymus weights were observed. Peripheral blood lymphocyte (PBL) number was consistently higher in treated rats throughout the treatment; the number of spleen cells decreased during the first 50 days, and then reached a level higher than in controls. NK activity, evaluated in a 4-h chromium release assay against YAC-1 target cells, was altered in treated rats: lower up to day 30, and then higher. In parallel, a reduction of the large granular lymphocytes (LGL) was found initially in the peripheral blood of Cd-treated rats, followed by a persistent marked increase. These changes were closely correlated with the altered distribution of CD8+ aGM1+ CD5- cells, which mostly consist of NK cells. Fluorescence-activated cell sorter (FACS) analysis revealed a decrease of cell subset with a typical NK phenotype during the first 30 days of treatment and a clear increase thereafter. Post-exposure observations indicated that all these effects disappeared with a return to control values 2 months after cessation of treatment. These findings suggest that in vivo administration of Cd induces both inhibitory and stimulatory effects on rat NK cell number and cytotoxic activity, depending on time of exposure.

Animals↗