Differential effects of eight metal ions on lymphocyte differentiation antigens in vitro

Abstract

In vitro studies were conducted to determine the effects of metal ions known to be released from metallic implants in vivo on the expression of lymphocyte surface antigens. Normal human peripheral blood lymphocytes were exposed to various concentrations of metal ions (Fe³⁺, Ni²⁺, Co²⁺, Mo⁶⁺, V⁵⁺, Cr⁶⁺, Cr³⁺, and Ti³⁺) for 30 min at 37°C in a 5% CO₂ atmosphere, and then analyzed for their ability to form rosettes with sheep red blood cells. Following this preliminary analysis, lymphocytes were exposed to the metal ions found to inhibit the E‐rosette reaction (Fe³⁺, Ni²⁺, and Co²⁺) in order to determine which of the following surface antigens were affected: CD2, CD3, CD4, CD8, CD1, CD22, CD10, and HLA‐DR. Our results showed that the in vitro treatment of lymphocytes with Fe³⁺ or Co²⁺ caused inhibition of CD2 only, whereas Ni²⁺ caused inhibition of both CD2 and CD3 antigens. These findings suggest that Fe³⁺, Co²⁺, and Ni²⁺ ions may interfere with T cell activation since both CD2 and CD3 are involved in that process.