STAINLESS-STEEL CORROSION PRODUCTS CAUSE ALTERATIONS ON MOUSE SPLEEN CELLULAR-POPULATIONS

Stainless steel is a metallic biomaterial commonly used in orthopaedic surgery. In this study we looked at the effects of stainless steel co rrosion products on spleen, in order to evaluate their potential immun otoxicological effects. For this purpose stainless steel, type AISI 31 6L, was electrochemically dissolved in a physiological salt solution. The final solution, containing 490 mu g/ml Fe, 224 mu g/ml Cr and 150 mu g/ml Ni, was injected subcutaneously in mice. After several periods of time (4, 10 and 14 days) spleens were removed and analysed for: (a ) their contents in Fe, Cr and Ni, (b) histological alterations, (c) e numeration of cellular populations. Results showed that stainless stee l corrosion products accumulated in spleen, caused histological altera tions, and induced changes in cellular populations. When compared to c hromium and nickel, iron was the metal ion preferentially accumulated in spleen. The increase of the multinucleated giant cell population wa s accompanied by depletion of lymphocyte populations. This study indic ates that stainless steel corrosion products can spread systemically a nd accumulate in spleen inducing histological and cellular alterations which may give rise to immunotoxicological consequences.