Effects of trichloroethylene on hepatic and splenic lymphocytotoxic activities in rodents

Abstract

The effects of trichloroethylene (TRI), a widely used industrial solvent, on various immunological and toxicological parameters have been examined in Sprague-Dawley rats and B6C3F1 mice. Rats were administered TRI in vivo at 0.05, 0.5 and 5.0 mmol/kg per day intraperitoneally (i.p.) for 3 days. Mice were similarly treated with TRI at 10.0 mmmol/kg. The highest TRI dose resulted in decreased splenocyte count and relative spleen weights, in rats and mice respectively and inhibition of hepatic natural killer cell (NK), natural cytotoxic cell (NC) and NPK cell (a new described immune cell killing) activities in both rats and mice. High dose TRI in vitro resulted in minor decreases (< 10 %) in splenocyte viability, inhibition of LPS-stimulated mitogenesis in rat cells and marked inhibitions of NK and NC activities in all groups of effector cells. At the lowest in vitro dose mouse hepatic NK activity was still inhibited. Overall the data show that TRI is able to inhibit the activity of lymphocytotoxic cells which are involved in the immune surveillance of cancerous cells. This inhibition is particularly evident in the liver after in vivo administration and both liver and spleen cells after in vitro exposure. This suggests the possibility that compromised immune function may play a role in the carcinogenic responses in experimental animals on exposure to TRI.